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Carnival Cruise Lines Hit With $20 Million Penalty For Environmental Crimes

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Princess Cruise Lines and its parent company Carnival Corporation have agreed to pay a $20 million criminal penalty for environmental violations. Casey Rodgers/AP hide caption

Princess Cruise Lines and its parent company Carnival Corporation have agreed to pay a $20 million criminal penalty for environmental violations.

The cruise line giant Carnival Corporation and its Princess subsidiary have agreed to pay a criminal penalty of $20 million for environmental violations such as dumping plastic waste into the ocean. Princess Cruise Lines has already paid $40 million over other deliberate acts of pollution.

U.S. District Judge Patricia Seitz approved the terms of the deal during a hearing Monday in Miami. She had appeared to grow increasingly frustrated as the company continued to flout environmental laws during the course of the years-long case.

"You not only work for employees and shareholders. You are a steward of the environment," she told Carnival CEO Arnold Donald, who attended the hearing with other senior executives. "The environment needs to be a core value, and I hope and pray it becomes your daily anthem."

The Two-Way

Princess cruises hit with largest-ever criminal penalty for 'deliberate pollution'.

Miami-based Carnival pleaded guilty Monday to six probation violations, including the dumping of plastic mixed with food waste in Bahamian waters. The company also admitted sending teams to visit ships before the inspections to fix any environmental compliance violations, falsifying training records and contacting the U.S. Coast Guard to try to redefine what would be a "major non-conformity" of their environmental compliance plan.

"I sincerely regret these mistakes. I do take responsibility for the problems we had," Arnold told the judge. "I'm extremely personally disappointed we have them. I am personally committed to achieve best in class for compliance."

Carnival has had a long history of dumping plastic trash and oily discharge from its ships, with violations dating back to 1993.

Environmental groups such as Stand.earth say they are tired of seeing the company hit with penalties "that cannot even be characterized as a slap on the wrist."

"Today's ruling was a betrayal of the public trust and a continuation of the weak enforcement that has allowed Carnival Corporation to continue to profit by selling the environment to its passengers while its cruise ships contribute to the destruction of the fragile ecosystems they visit," Kendra Ulrich, a senior shipping campaigner at Stand.earth, said in a statement.

Carnival's Earnings Hit By String Of Cruise Ship Problems

When Princess was fined the $40 million in 2016, the Department of Justice called it "the largest-ever criminal penalty involving deliberate vessel pollution." The company also agreed to plead guilty to seven felony charges for violations on five ships starting as early as 2005.

In 2013, a whistleblowing engineer exposed the illegal dumping of contaminated waste and oil from the company's Caribbean Princess ship. He told authorities that engineers were using a special device called the "magic pipe" to bypass the ship's water treatment system and dump oil waste straight into the ocean. The company also tried to cover up this practice from investigators, according to the Justice Department.

At the time, Princess told NPR that it chalked up the violations to "the inexcusable actions of our employees."

Part of the 2016 plea agreement required ships from eight of Carnival's companies to submit to court-supervised monitoring, which is how the most recent violations were discovered.

Judge Seitz had recently threatened to block Carnival from docking at U.S. ports. She also had requested that the company's senior executives attend Monday's hearing because she said she was convinced they weren't serious about complying with environmental laws.

In addition to the $20 million criminal penalty, Carnival has agreed to pay for 15 annual audits — on top of about three dozen ship and shore-side audits it's already on the hook for — and says it will restructure its corporate compliance efforts. If the company does not meet court-imposed deadlines for that restructuring, it will be fined up to $10 million per day.

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6 Ways Cruise Ships are Destroying the Oceans

Cruise ships are a popular way to travel, offering passengers a chance to visit multiple destinations while enjoying luxurious amenities on board.

However, these massive ships have a significant impact on the environment, particularly the oceans they travel through.

In fact, cruise ships are responsible for a wide range of ocean pollution , from wastewater discharge to oil spills.

Before you book your next cruise, read more below to learn about the harsh reality of the cruise ship industry and its impact on our marine environment.

Table of Contents

Direct Discharge of Waste

Cruise ships generate a significant amount of waste, including air emissions, ballast water, wastewater, hazardous waste, and solid waste. One of the most significant ways cruise ships cause ocean pollution is through the direct discharge of waste into the ocean.

According to a study conducted on Southampton, cruise ships can discharge untreated oily bilge water, which can damage marine life and ecosystems. If the separator, which is usually used to extract oil, is faulty or deliberately bypassed, untreated oily bilge water could be discharged directly into the ocean .

Food waste is another type of waste generated by cruise ships, and it can also be discharged directly into the ocean.

While minimal attention is paid to food waste management by many ships and catering typical of cruise liners, it can still have a significant impact on the environment.

The direct discharge of waste from cruise ships can also include untreated wastewater, which can contain pathogens, nutrients, and other contaminants. This wastewater can be harmful to marine life and ecosystems, and it can also contribute to the growth of harmful algal blooms.

To reduce the impact of direct waste discharge, some regulations have been put in place. However, there is still a need for more stringent regulations and enforcement to ensure that cruise ships do not cause further harm to the ocean and its inhabitants.

Air Pollution from Cruise Ships

Cruise ships are one of the major sources of air pollution in the world. The emissions from these ships have a significant impact on the air quality of the surrounding areas, including coastal cities and ports.

Emission of Greenhouse Gases

Cruise ships emit significant amounts of greenhouse gases, including carbon dioxide, methane, and nitrous oxide.

These gases contribute to global warming and climate change. According to a study published in Science Direct, the emissions from cruise ships in the port of Naples, Italy, impacted the air quality of the surrounding areas.

The study found that while cruise ship emissions were not the sole source of air pollution in the port, they did contribute to the overall levels of pollution.

Release of Sulfur Dioxide

Cruise ships also release sulfur dioxide, a harmful gas that can cause respiratory problems and acid rain. According to a study published in Science Direct, the energy consumption and emissions of air pollutants from ships in harbors in Denmark were measured.

The study found that sulfur dioxide emissions from cruise liners were higher than other types of ships, and the emissions were highest when the ships were docked.

To reduce air pollution from cruise ships, some countries have implemented regulations that require ships to use cleaner fuels and technologies.

For example, in 2020, the International Maritime Organization (IMO) implemented new regulations that require ships to use fuels with a lower sulfur content. While these regulations are a step in the right direction, more needs to be done to reduce the impact of cruise ship emissions on air quality.

Cruise Ships and Oil Spills

Cruise ships are a significant source of oil pollution in the ocean. Accidental oil spills from cruise ships can cause significant harm to marine life and the environment.

According to a study published in the Journal of Marine Pollution Bulletin, cruise ships have the potential to contribute to accidental oil spills due to their large size and the amount of fuel they carry [1] .

One of the main sources of oil pollution in the ocean is from cruise ships. In a study conducted in Ha Long Bay, Vietnam, it was found that oil spills from sunken cruise boats were responsible for more than 60% of biodiesel and petroleum diesel spills in the area [2] .

The impact of oil spills from cruise ships can be devastating to marine life and the environment. Oil spills can harm marine mammals , fish, and birds, and can also impact coastal habitats and beaches.

In a study published in the Journal of Environmental Science and Pollution Research, it was found that oil spills can cause both short-term and long-term damage to marine ecosystems [3] .

To prevent oil spills from cruise ships, it is essential to have proper regulations and management in place. Alaska’s Commercial Passenger Vessel Compliance Program has been cited as a model for other states to follow.

The program has implemented strict regulations for cruise ships to prevent oil spills and protect the environment [4] .

Impact on Marine Life

Cruise ships are known to cause significant harm to marine life due to their pollution. The following sub-sections describe how noise pollution and destruction of coral reefs are two ways that cruise ships impact marine life.

Noise Pollution

Noise pollution from cruise ships can have a significant impact on marine life, particularly on species that rely on sound for communication, navigation, and hunting.

Noise pollution can cause hearing loss, stress, and behavioral changes in marine animals, which can ultimately lead to decreased reproduction rates and population decline.

Destruction of Coral Reefs

Cruise ships contribute to the destruction of coral reefs in several ways, including anchoring, sewage discharge, and the release of chemicals.

Anchoring can cause physical damage to coral reefs , while sewage discharge and chemical releases can lead to water pollution, which can harm coral and marine life.

In addition, the large amount of waste generated by cruise ships can cause nutrient imbalances in the water, leading to the growth of harmful algae that can suffocate and kill coral reefs.

Cruise Ships and Plastic Pollution

Cruise ships are notorious for generating a significant amount of plastic waste, which is a major contributor to ocean pollution.

Single-use plastics: Cruise ships are known for providing passengers with single-use plastics such as straws, cups, and cutlery. These items are often used once and then discarded, contributing to the plastic waste that ends up in the ocean.

Packaging waste: In addition to single-use plastics, cruise ships generate a significant amount of packaging waste from items such as food and beverage containers, toiletries, and souvenirs.

Improper waste management: Despite regulations and guidelines for waste management, some cruise ships still dispose of plastic waste improperly, either by dumping it into the ocean or by not properly recycling it.

Graywater contamination: Cruise ships generate a significant amount of graywater, which can contain microplastics from sources such as laundry detergents and personal care products. This contaminated water can be discharged into the ocean, contributing to plastic pollution .

Dumping of garbage: Some cruise ships have been caught illegally dumping garbage, including plastic waste, into the ocean. This not only contributes to plastic pollution but also violates international laws and regulations.

Lost or discarded fishing gear: Cruise ships may accidentally or intentionally lose or discard fishing gear, such as nets and lines, which can entangle and harm marine life.

Port pollution: Cruise ships generate plastic waste not only while at sea but also while in port. This can contribute to plastic pollution in the surrounding waters and on nearby beaches .

Sewage Dumping from Cruise Ships

Cruise ships generate a significant amount of sewage waste, which is often disposed of in the ocean.

The untreated sewage contains harmful pathogens and bacteria that can cause health problems for marine life and humans.

Volume of sewage: A single cruise ship can generate up to 1 million gallons of sewage waste per week. This volume of waste can cause significant damage to marine ecosystems if not properly treated and disposed of.

Untreated sewage: Many cruise ships discharge untreated sewage directly into the ocean, which can contain harmful bacteria and pathogens. This untreated sewage can cause health problems for marine life, including fish, dolphins, and whales , and can also pose a risk to humans who come into contact with contaminated water.

Marine life impact: The discharge of sewage waste can have a significant impact on marine life, including coral reefs, fish, and other sea creatures . The high levels of nitrogen and phosphorus in the sewage can cause harmful algal blooms, which can suffocate marine life and cause dead zones in the ocean.

Beach pollution: Sewage waste from cruise ships can wash up on beaches, causing pollution and health risks for beachgoers. The sewage can contain harmful bacteria that can cause skin infections, respiratory problems, and other health issues.

Illegal dumping: Despite regulations prohibiting the discharge of untreated sewage waste within certain distances from shore, some cruise ships continue to illegally dump sewage waste in the ocean. This illegal dumping can cause significant damage to marine ecosystems and pose health risks for humans.

Limited treatment facilities: Many ports of call do not have the necessary treatment facilities to properly treat sewage waste from cruise ships. This can lead to the discharge of untreated sewage waste into the ocean, causing pollution and health risks for marine life and humans.

Inadequate regulations: The regulations governing the disposal of sewage waste from cruise ships are often inadequate, with many countries having no regulations in place to protect marine ecosystems and human health. This lack of regulation can lead to the discharge of untreated sewage waste into the ocean, causing pollution and health risks for marine life and humans.

Cruise ships contribute significantly to ocean pollution through the dumping of sewage waste. It is essential that proper regulations and treatment facilities are put in place to protect marine ecosystems and human health.

Frequently Asked Questions

How do cruise ships contribute to ocean pollution.

Cruise ships contribute to ocean pollution in many ways. They generate large amounts of waste, including sewage, gray water, and solid waste, which can contain harmful chemicals and pathogens.

They also emit air pollution, including sulfur dioxide, nitrogen oxides, and particulate matter, which can harm human health and the environment.

Additionally, cruise ships can damage marine ecosystems through activities such as anchoring, dredging, and discharging ballast water.

What are the main types of pollution caused by ships?

The main types of pollution caused by ships are air pollution, water pollution, and noise pollution. Air pollution is caused by emissions from ship engines and includes sulfur dioxide, nitrogen oxides, and particulate matter.

Water pollution is caused by discharge of untreated sewage, gray water, and ballast water, which can contain harmful chemicals and pathogens. Noise pollution is caused by ship engines, which can disrupt marine ecosystems and harm marine mammals.

What are some of the environmental impacts of cruise ships?

Cruise ships can have a range of environmental impacts, including damage to marine ecosystems, harm to marine mammals, and contribution to climate change.

They can also affect local air and water quality, and contribute to the spread of invasive species .

What is the impact of cruise ship emissions on air and water quality?

Cruise ship emissions can have a significant impact on air and water quality. Air pollution from ship engines can harm human health and contribute to climate change.

Water pollution from untreated sewage, gray water, and ballast water can harm marine ecosystems and contaminate local water sources.

How can we reduce the pollution caused by cruise ships?

There are several ways to reduce the pollution caused by cruise ships. These include using cleaner fuels, such as liquefied natural gas, improving waste management practices, and implementing technologies that reduce air and water pollution.

Additionally, regulations and policies can be put in place to limit the environmental impacts of cruise ships.

What are the long-term consequences of cruise ship pollution on marine life and ecosystems?

The long-term consequences of cruise ship pollution on marine life and ecosystems can be significant. Pollution can harm marine mammals, disrupt food chains, and damage coral reefs and other sensitive habitats.

Additionally, pollution can contribute to the spread of invasive species, which can have long-term impacts on local ecosystems.

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Here's how the 'world's largest cruise ship' recycles millions of pounds of water, food and waste

• Royal Caribbean's Symphony of the Seas has a high-tech recycling system.
• The Symphony of the Seas is a 361-meter — nearly 1,200 feet — cruise liner.
• The ship's crew can process up to 13,000 pounds of glass in a week-long cruise.

Cruise ships produce a lot of trash, but there are no garbage trucks to come and pick up waste when they're out at sea. So, where does all the garbage go?

The Symphony of the Seas is one of the largest cruise ships in the world. Built-in 2018, the Royal Caribbean ship is 1,188 feet long and weighs a total of 228,081 gross tons, according to the cruise line . 

Waste disposal is a problem cruise lines have been dealing with for years.

Princess Cruise Lines was fined $40 million in 2016 after pleading guilty to seven felony charges for illegally dumping oiled waste into the sea, according to The New York Times .

In 2019, a federal judge ordered Carnival Cruise Lines to pay $20 million in fines for dumping plastic waste into the ocean and other environmental violations, NPR reported .

Cruise lines started designing ways to purify water and handle waste inside their ships.

Stewart Chiron, a cruise ship expert, told Insider that Carnival Cruise Lines issues "really brought the need for better technology so that she ships can operate more efficiently."

"Up until now, the options weren't available," Chiron said.

Cruise ships are notorious for disposing of waste in ways that are hazardous to the environment. In 2019, cruise ships dumped more than 3 million pounds of garbage in Juneau, Alaska, according to Alaska Public Media.

Carnival Cruise Lines' Symphony of the Seas is a "zero landfill ship," which means it uses recycling and water filtration to deal with its own waste.

Alex Mago, environmental officer for the Symphony of the Seas, told Insider that the waste management team separates the ship's trash into recyclables on a lower deck.

The ship's crew is made up of around 2,200 crew members, according to Royal Caribbean .

The ship's crew separates glass into colors and can process up to 13,000 lbs of glass for a week-long cruise.

Each one of the ship's 36 kitchens has a suction drain.

Food waste from Royal Caribbean cruises is dropped no less than 12 miles from land, according to the company's waste management guidelines .

"Food waste produced on board is sent to a pulper and pulverized to less than 25 mm, as per international standards, and discharged no closer than 12 nautical miles from land," the guidelines state.

Food waste is carried through a giant pipe to a food processor at the bottom of the ship, where it is incinerated.

The ship's crew crushes around 528 gallons of water bottles per week.

The ship is dependent on water bottles because cruise ships are not allowed to have water fountains for health and safety reasons. 

Cardboard and aluminum cans are sent through a bailer.

The Symphony of the Seas has two incinerator rooms.

The ship's incinerator room has two incinerators and is manned around the clock by 10 crew members.

Cubes of aluminum trash are stored in a refrigerator to prevent the smell from spreading to other parts of the ship for up to seven days.

Grey water, from sinks, laundries, and drains and black water, from toilets, are mixed together in a water purification system before being dumped back into the sea.

The purification system runs several cleansing processes until the water is above the United States federal standard. 

When the ship docs in Miami, the plastic, paper, and glass are offloaded to go to partner recycling facilities.

According to Royal Caribbean , the company recycled more than 14 billion pounds of waste in 2021.

See more about this story below 

• Main content

Matador Original Series

Where Does the Waste Go on Cruise Ships, and Is It Really Sustainable?

D on’t pretend it hasn’t crossed your mind. When you flush a cruise ship toilet and hear that rapid, louder-than-usual whooshing sound, you wonder as you stare at the empty bowl … “where does it all go?” On land, we have all kinds of easy explanations. We have sewer systems that pump to sewage treatment plants where the waste is processed and treated. But at sea, when you may not be making landfall for days, what happens to it?

You wander out of the bathroom and onto your private balcony, where you sit and stare out at the vast sea. Then it hits you. “What about everything else?” It’s not just human waste that seemingly has nowhere to go in the middle of the ocean, but food waste, plastic waste, and pretty much everything else we mindlessly toss in the trash. There are no dumpsters around the corner, no recycling plants nearby. How do cruise ships dispose of waste in a sustainable manner, so that doesn’t do irreparable harm to the environment?

Nothing that’s human-made in this world is 100 percent sustainable. That said, as public attention to sustainability efforts across all industries has increased, cruise ships have implemented a number of sophisticated treatment and recycling programs for everything from sewage and organic waste to landfill diversion in order to minimize the environmental impact of leisure on the water.

How waste disposal actually works

First of all, before we start talking about getting rid of waste — what happens to it on the ship? It has to be stored somewhere until it’s ready to be discharged, after all.

“Human waste is processed through our advanced wastewater treatment system,” Sarah Dwyer, Sustainability Program Manager for Virgin Voyages , tells Matador Network . “This system processes all blackwater (toilets), greywater (sinks and showers), laundry water, galley greywater, and food waste reject water to comply with MARPOL (International Convention for the Prevention of Pollution from Ships) regulations.”

The process is similar on Uniworld Boutique River Cruises although waste storage on a smaller river ship will differ somewhat from storage on a huge ocean liner.

“Human waste is collected in a tank (with a bacteria system) and this is emptied regularly, depending on where the ships are docked and whether we have access to the local sewerage system or if we have an external company coming to pump it out,” Julie Higgins, Sustainability Officer for Uniworld Boutique River Cruises, tells Matador Network . “For food waste, each ship has a geographical partner that either collects the food waste for animal feed or uses it for biofuel creation. These pickup points are fixed according to each itinerary.”

It’s not exactly surprising that cruise ships have pretty well-developed and intricate methods of getting rid of their waste. On Uniworld, both collection and offloading are more frequent, given the closer proximity of port.

Food waste is “collected by various companies, while human waste is collected in tanks on board each ship and then disposed of either directly into the city or town sewerage system,” Higgins says. “Otherwise, we have companies that come and collect it from our tanks when this is not possible depending on port facilities.”

As for larger ships like those operated by Virgin Voyages, waste must be discharged a certain distance from shore, or stored in a special recycling center for offloading.

“For our advanced wastewater treatment process, effluent (liquid waste or sewage) is held on board and then discharged at distances greater than three nautical miles from shore,” Dwyer says. “Food waste is either pulverized and discharged (12 nautical miles from shore and at a speed greater than six knots), or it’s stored in our waste recycling center to be offloaded in port.”

Is waste disposal actually sustainable?

The big complaint facing cruise lines is the issue of sustainability. From carbon emissions to how waste impacts the surrounding ecosystem, there are very real concerns about the impact cruises have on the ocean. That’s why environmental regulations are tighter than ever, and cruise lines have implemented strict treatment methods to limit any harm done by waste disposal.

“Our advanced wastewater treatment system is calibrated to meet stringent water quality standards under MARPOL and the US Clean Water Act,” Dwyer says. “Our crew ensures that our vessels are in compliance with the the National Pollutant Discharge Elimination System and Vessel General Permit, which are monitored by the Environmental Protection Agency.”

What does this actually mean? Well, everything from wastewater treatment methods to offloading strategies that divert waste from landfills.

“Our wastewater is treated by the bacteria within our tanks on board, which forms something we call ‘sludge,’” Higgins says. “We then dispose of this ‘sludge’ responsibly … over the years we have formed a reliable network that allows us to dispose in a responsible manner and not pollute the areas we sail through.”

The most visible part of Virgin Voyages’ sustainability program is its reduction of single-use plastics on board, as well as incorporating more sustainable materials for its passengers. From banning plastic utensils to using reusable food containers in restaurants, the goal is to limit how much non-recyclable waste is even produced in the first place.

“We collect and sort recyclable waste on board, which is then offloaded in our primary ports such as Miami,” Dwyer says. “We also have a recycling takeback program from our beach club operation in Bimini (Bahamas) to limit recyclable materials that would otherwise be sent to the landfill. We also vet the waste providers that we partner with on-shore to ensure waste is handled appropriately.”

In an industry that’s inherently not known for sustainability, it’s clear that cruise lines do all they can to reduce their environmental impact. But is it enough?

The impact of waste disposal on the ocean

While many cruise lines take sustainability seriously and ensure their waste management systems are up to code, that’s not always the case, resulting in harmful pollutants entering the ocean.

“Several cruise ships still use scrubber technology, which discharges a toxic cocktail of petroleum byproducts from ships directly into the ocean with little to no treatment,” Marcie Keever, Oceans Program Director at Friends of the Earth , tells Matador Network . “The ICCT (International Council on Clean Transportation) estimates that in one year, ships worldwide will emit at least 10 gigatons of scrubber wastewater, approximately 15 percent of which comes from the cruise industry.”

She also believes more oversight is needed to ensure the cruise industry’s sustainability standards are as strict as they should be. And indeed, however strict those regulations might be, without proper oversight, the rules themselves (if frequently broken) are irrelevant.

“The cruise industry remains a major contributor to air and ocean pollution, repeatedly failing health compliance and environmental tests,” she claims. “At the federal level, Homeland Security and the EPA provide little regulation enforcement and no oversight on wastewater discharge or public health, even though cruise ships continue to be a major spreader of harmful pathogens like COVID-19.”

Indeed, Carnival was fined in 2019 for dumping waste into the ocean. Apart from ocean water, Keever notes cruise ports themselves are also a serious victim of cruise ship waste.

“One community in Alaska fought hard against the industry after being filled with trash and sewage from ships,” she says. “In addition, carbon emissions from ships harm the places where they dock. Friends of the Earth is working to help ports electrify to reduce carbon emissions and improve air quality for surrounding communities.”

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Press Releases

Royal caribbean group transforms waste management in the cruise industry, helping protect the oceans.

MIAMI – July 11, 2023 – Royal Caribbean Group (NYSE: RCL) is building on its industry-leading waste management practices by introducing the next generation of technology to make its way to the high seas. These tools, from waste-to-energy systems, food waste applications and an expanded network of green hubs, are a result of the cruise company’s relentless drive to deliver the best vacation experiences responsibly.

Debuting this year, on two of the cruise company’s newest ships, will be the cruise industry's first systems to turn solid waste directly into energy on board.

“I am proud of Royal Caribbean Group’s drive to SEA the Future and be better tomorrow than we are today,” said Jason Liberty, president and CEO, Royal Caribbean Group. “Pioneering the first waste-to-energy system on a cruise ship builds on our track record of waste management and furthers our commitment to remove waste from local landfills and deliver great vacation experiences responsibly.” Solid Waste to Energy at Sea The systems, Microwave-Assisted Pyrolysis (MAP) and Micro Auto Gasification (MAG), debuting respectively on Royal Caribbean International’s Icon of the Seas and Silversea Cruises' Silver Nova , will take waste on board and convert it into synthesis gas (syngas) that the ship can directly use as energy. Much like land-based waste-to-energy facilities, the result is repurposing waste in an efficient and sustainable way. An additional bioproduct of the system, biochar, can also be used as a soil nutrient.

Reducing Food Waste Royal Caribbean Group is also looking at waste management from start to finish, including its plans to reduce food waste across the fleet by 50% by 2025. To do so, the cruise company is implementing initiatives across its brands including:

• Developing a proprietary platform to monitor food supply and accurately estimate how much food should be produced, prepped and ordered on a given day.
• Using artificial intelligence (AI) to adjust food production in real time.
• Introducing a dedicated onboard food waste role to monitor and train crew members.
• Tracking guest demand for specific menu items and adjusting menu preparation and ordering accordingly.
• Partnering with World Wildlife Fund (WWF) to introduce a food waste awareness campaign in the crew dining areas fleetwide.

To date, Royal Caribbean Group has achieved a 24% reduction in food waste by focusing on the frontend of the food system, which prevents and addresses many of the main causes of food waste, including inventory management and over-preparing.

Expanding Green Hubs Since the company’s first environmental initiative, Save the Waves, aimed at ensuring no solid waste goes overboard, Royal Caribbean Group has worked diligently to increase accountability and strengthen responsible waste management practices. To do so, it developed Green Hub, a capacity-building program to identify waste vendors in strategic destinations that has helped divert 92% of its waste from landfills. Since its start in 2014, the program has grown to 33 ports worldwide.

Now joining the Green Hub program is the Galapagos Islands, where Silversea became the first operator to gain certification in environmental management by diverting all waste from landfill. Initiatives like this allow Royal Caribbean Group to continue to safeguard the delicate ecosystem of the Galapagos for future generations.

Championing the Environment With a sustainability journey that began over 30 years ago, Royal Caribbean Group has remained steadfast in its commitment to innovate and advance the solutions necessary for a better future. Building on a robust portfolio of technologies that improve energy efficiency, water treatment and waste management, incorporating waste-to-energy systems is an extension of the company's commitment to reach beyond the expected and SEA the Future to sustain the planet, energize the communities in which it operates and accelerate innovation.

To learn more about how Royal Caribbean Group connects people to the world's most beautiful destinations while respecting and protecting ocean communities and ecosystems, visit www.royalcaribbeangroup.com/SEAtheFuture .

Media Contact:

[email protected]

About Royal Caribbean Group

Royal Caribbean Group (NYSE: RCL) is one of the leading cruise companies in the world with a global fleet of 64 ships traveling to approximately 1,000 destinations around the world. Royal Caribbean Group is the owner and operator of three award winning cruise brands: Royal Caribbean International, Celebrity Cruises, and Silversea Cruises and it is also a 50% owner of a joint venture that operates TUI Cruises and Hapag-Lloyd Cruises. Together, the brands have an additional 10 ships on order as of March, 31, 2023. Learn more at www.royalcaribbeangroup.com or www.rclinvestor.com.

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Cruise industry faces choppy seas as it tries to clean up its act on climate

• Medium Text

• The cruise industry is the fastest growing in tourism and is expected to exceed pre-COVID record highs in passenger numbers and revenues by next year
• The industry promises to make zero-emission vessels and fuels widespread by 2030, and to achieve a goal of 'net-zero carbon' cruising by 2050
• Environmental groups cite its record on pollution, greenhouse gas emissions, and over-tourism, and raise doubts about its ability to reach goals
• Concerns include widespread use of "scrubbers", LNG as transition fuel, and limited capacity for shore-based power in ports

Caroline Palmer is a freelance journalist specialising in business, health, sustainability and the artisan economy. She has worked for the Financial Times, The Guardian and The Observer and is a contributor to Ethical Corporation magazine.

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Original research article, sources and leakages of microplastics in cruise ship wastewater.

• 1 Department of Environmental Sciences, Faculty of Science, Open Universiteit, Heerlen, Netherlands
• 2 Cartagena Convention Secretariat, United Nations Environment Programme, Kingston, Jamaica

To date, the contribution of sea-based sources to the global marine litter and plastic pollution problem remains poorly understood. Cruise ships produce large amounts of wastewater and concentrate their activities in fragile and ecologically valuable areas. This paper explores for the first time the sources of microplastics in cruise ship wastewater, as well as their pathways from source to sea. It thereto uses a novel approach for the identification of sources and pathways, based on scientific literature on microplastic sources and pathways, literature on cruise operations and wastewater management as well as a questionnaire among cruise lines. The study highlights personal care and cosmetic products, cleaning and maintenance products and synthetic microfibers released from textiles in laundry as relevant source categories. Untreated grey water and the overboard discharge of biosludge, resulting from the treatment of sewage and grey water, were identified as key pathways. Cruise lines can reduce microplastic emissions by adapting their purchasing policies for personal care, cosmetic, cleaning and maintenance products and professional textiles. In addition, the holistic management of all wastewater streams and resulting waste products is essential to prevent leakages of microplastics from cruise ships to vulnerable coastal and marine ecosystems. Furthermore, the approach can be used to guide company-level assessments and can be modified to address microplastic leakages in other maritime sectors.

1 Introduction

Marine litter is a problem of emerging concern and research efforts as well as initiatives to address the problem are developing rapidly ( UNEP, 2021 ). Recently, a breakthrough was achieved at the United Nations Environments Assembly (UNEA-5.2), where 175 nations committed to forge an international legally binding agreement to end plastic pollution by 2024, addressing the full lifecycle of plastic from source to sea 1 . Marine litter is defined as “any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment” ( UNEP, 2021 ). While the term embraces different types of materials, plastics constitute the largest proportion ( Galgani et al., 2015 ). Jambeck et al. (2015) estimated that in 2010, 4.8 to 12.7 million MT of plastics entered the ocean, and inputs are expected to increase over the coming decades ( Lebreton and Andrady, 2019 ). Plastic can travel long distances and is found in all parts of the marine ecosystem, even in very remote locations such as in Arctic sea ice ( Obbard et al., 2014 ) and the Mariana Trench ( Chiba et al., 2018 ). Microplastics (MPs) are small pieces of plastic, with a size smaller than 5 mm. MPs comprise both manufactured microscopic plastic particles (primary MPs), such as microbeads with applications in the cosmetic industry and industrial pellets used for the production of plastics, and particles that result from the abrasion and degradation of larger items (secondary MPs) ( Cole et al., 2011 ). MPs in the marine environment can be ingested or inhaled through the gills by a wide range of organisms ( Wright et al., 2013 ; GESAMP, 2016 ; Hantoro et al., 2019 ). Once ingested, MPs may block or damage intestinal tracts ( Cole et al., 2011 ; Wright et al., 2013 ). They can also be absorbed through the gut walls ( Foley et al., 2018 ). In addition, MPs may leach toxic pollutants, including chemicals that are intentionally added during plastic production as well as organic contaminants and heavy metals that sorb to the MP surface ( Teuten et al., 2009 ; Rochman et al., 2014 ). Impacts that have been associated with MP ingestion in marine biota include adverse effects on feeding (e.g. Wegner et al., 2012 ), growth (e.g. Au et al., 2015 ), reproduction (e.g. Della Torre et al., 2014 ) and survival (e.g. Luίs et al., 2015 ). Besides the effects at the individual level, MPs as well as pollutants absorbed by MPs, can be transferred through food webs ( Farrell and Nelson, 2013 ; Setälä et al., 2014 ) and induce ecological impacts ( Rochman et al., 2016 ). Human health may also be affected by MPs in the marine environment through the consumption of contaminated seafood ( Hantoro et al., 2019 ; Campanale et al., 2020 ).

In order to effectively address marine litter and (micro-)plastics, it is necessary to understand the contribution of individual sources and the pathways from these sources to the environment. Assessing the origin of MPs in the environment is complicated ( Hardesty et al., 2017 ) and the relative contribution of different sources and pathways is strongly dependent on local conditions ( Duis and Coors, 2016 ). While it is generally assumed that most marine litter derives from land-based sources, the contribution from sea-based source varies strongly by geographic location and could be substantial for specific locations ( GESAMP, 2021 ). Knowledge about sea-based sources is still little developed compared to land-based sources; the GESAMP (Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection) Working Group on sea-based sources of marine litter concluded that knowledge of the type, quantity and impact of sea-based sources is lacking ( GESAMP, 2021 ), thus hindering the development of effective mitigation strategies. Ship-based sources contribute to MP pollution, e.g. through paints and coatings, abrasives used for the cleaning of ship hulls during maintenance, loss of cargo (e.g. plastic pellets) and discharges of wastewater ( Boucher and Friot, 2017 ; Bray, 2019 ; GESAMP, 2021 ). In terms of wastewater, cruise ships would be of particular interest because of the large quantities of wastewater that are generated on board these ships ( GESAMP, 2021 ). Vicente-Cera et al. (2019a) estimate that the world cruise fleet produced about 34.000.000 m 3 of wastewater in 2017; a production rate that is comparable to that of the country Cyprus 2 .

Until the start of the COVID-19 pandemic, the cruise industry had shown a constant growth, from 17.8 million passengers in 2009 to 29.7 million passengers in 2019 3 : an increase of 75% in 10 years. The pandemic led to a complete halt of operations; however, the industry expects a full recovery compared to 2019 levels by 2023 and a growth of 12% by 2026 4 . Currently, the largest cruise ship in operation can carry up to 6988 passengers and 2300 crew members 5 . Besides a means of transportation and accomodation, cruise ships typically provide a wide array of onboard services and attractions to their passengers, such as swimming pools, spas, theatres and sports facilities. The main mainstream cruise destinations are located the Caribbean, the Mediterranean and Northwestern Europe; specialty “adventure” types of cruises attend extremely remote and vulnerable environments ( Lamers et al., 2015 ) such as the Arctic and Antarctic. Around 70% of the cruise destinations are located in biodiversity hotspots ( Lamers et al., 2015 ) and cruise ships frequently pass through fragile coastal and shallow areas as well as marine protected areas, especially when entering or leaving ports ( Lloret et al., 2021 ). Caric et al. (2019) highlight that in the Mediterranean, cruise ships frequently anchor in close proximity of many marine protected areas (MPAs) and the heavily trafficked cruise port of Venice is even located within such a site. Considering that cruise activities typically concentrate in certain coastal areas and routes, these vulnerable areas are exposed to cumulative environmental impacts of these activities ( Toneatti et al., 2020 ). With increasing cruise intensity, the impacts of the industry, including MP pollution, are likely to increase in the coastal and marine environment.

This study aims to highlight characteristics of the cruise sector that affect the potential for MPs being found in wastewater discharges, and provide recommendations to guide and set-up future research efforts as well as indicate general directions for mitigation. It thereto uses a novel approach for the identification of these sources and pathways, based on scientific literature on MP sources and pathways, literature on cruise operations and wastewater management as well as a questionnaire among cruise lines. First, an inventory was made of sources of MPs in the marine environment, based on general scientific literature. From this general inventory those sources were selected that are relevant to cruise operations and additional source categories were identified based on the characteristics of cruise operations and facilities. Subsequently, the identified sources were linked to the different wastewater streams and finally the management of each of these wastewater streams was evaluated.

2 Materials and Methods

Figure 1 presents an overview of the methodology for the identification of sources and pathways of MPs in cruise ship wastewater (detailed descriptions of the steps are described in the following paragraphs). Here, the term “sources” refers to the different applications of plastics and synthetic polymers on board cruise ships that have the potential to release. MPs to the marine environment. Through different release mechanisms, MPs find their way to the wastewater streams. Pathways are defined as the routes through which MP particles are transported to the marine environment, where the scope of this research is restricted to pathways through cruise ship wastewater discharges.

Figure1 Research steps in the identification of sources and pathways of microplastics in cruise ship wastewater.

2.1 Literature Review of Microplastic Sources

Since cruise ships are often characterized as “floating cities”, it was reasoned that MP sources on cruise ships have significant overlap with land-based urban sources of MPs. In addition, the maritime operations as well as any aspects that are unique to the cruise industry should be addressed. To identify and characterize sources of MPs, the research is based on the approach that was applied in different European countries, the European Union and the OSPAR region, as reported by Sundt et al. (2014) ; Lassen et al. (2015) ; Essel et al. (2015) ; Magnusson et al. (2016) ; Scudo et al. (2017) ; Verschoor et al. (2017) and Hann et al. (2018) . These studies estimate MP emissions at a local or regional scale, based on the sources and pathways of MPs reported in general literature in combination with local data on plastic uses and other relevant local factors. Lassen et al. (2015) define eight categories of primary MP sources and six categories of secondary MP sources, and identified the pathways from these sources to surface waters. This structure was adopted and the list was complemented with the results of other studies, reflecting all reported land-based and sea-based MP sources and pathways at national or regional level. Next, sources were selected that could be relevant for cruise ship wastewater during normal operations.

2.2 Cruise-Specific Functionalities

In order to cover all sources of MPs that are specific to the cruise industry, the following overarching types of MP sources were considered, representing different functionalities of cruise ships: cruise ship facilities, ship stores and people . Cruise ship facilities were further divided into hotel facilities and ship facilities , in accordance with the structure proposed by Lois et al. (2004) . The proposed facilities were supplemented by consulting Vogel et al. (2012) and Gibson and Parkman (2019) , as well as by studying the deck plans of the ten largest cruise ships in the world, in order to cover the main facilities that are present on modern cruise ships. Stores comprise the different purchasing streams of cruise ships: fuel, corporate, technical and hotel purchasing ( Véronneau and Roy, 2009 ). Finally, personal belongings of passengers and crew may act as MP sources; these are covered by the category “ people ”.

2.3 Inventory of Microplastic Sources

Following the identification of the main MP source categories on board cruise ships, the inventory as derived from the literature study was further developed and supplemented to cover those categories that have relevance to cruise ships. This was done by crosschecking the identified categories as derived from literature on the one hand and the identified facilities, stores and people categories from the previous step on the other. This approach resulted in the elimination of some of the MP sources that were identified in the previous step, because of differences in the characteristics of these sources on board cruise ships compared to the general characteristics that are described in literature. On the other hand, cruise-specific sources were added to the general inventory. The contribution of specific facilities and stores to MP pollution is not always straightforward and requires a thorough understanding of operations, facilities and the types of stores. The details of many specific cruise operations are not extensively reported in literature, and only to a limited extent in grey literature. Therefore, in order to assess the relevance of the different facilities and stores, Google searches were used to identify open access online resources, such as deck plans and pictures of the 10 largest cruise ships (e.g. to understand the application of artificial grass and the organization of laundry facilities) as well as blogs and YouTube videos, concerning the specific cruise ship operations and facilities such as laundry installations and engine room operations. In addition, experts were consulted to verify the findings (see below).

2.4 Linking Wastewater Streams to Microplastic Sources

In order to establish links between the sources on the one hand and wastewater streams on the other, the different sub-streams of the wastewater streams were identified based on literature. Then, the pathways from the identified sources to the different wastewater streams were assessed, by crosschecking each of the sources to the identified wastewater streams and vice versa.

2.5 Wastewater Management

The objective of this step was to map the main routes of the different wastewater streams and the key characteristics of treatment processes, where applicable, in order to identify potential pathways of MPs from the different wastewater streams. In addition, the characteristics of common treatment technologies were described. The assessment is based on scientific literature as well as grey literature. In order to verify the findings based on the grey literature, experts were consulted and a questionnaire was distributed among cruise lines.

2.6 Expert Consultation and Questionnaire

A preliminary version of the inventory of sources and pathways of MPs on board cruise ships was reviewed by experts in the fields of marine litter (3 experts) and MPs in onshore wastewater (1 expert). The typical practices and systems for wastewater management on board cruise ships were discussed with two experts in the field of maritime wastewater management and one cruise industry representative. In addition, a questionnaire was developed and distributed among cruise lines to verify the preliminary findings and collect additional industry-specific information. The questionnaire was distributed in February 2020 to the environmental managers of different cruise lines through the Cruise Lines International Association (CLIA). It consisted of a general section, where respondents could indicate the fleet size, a general wastewater management section and sections related to different wastewater treatment technologies. The final section concerned the measures and policies addressing MPs in wastewater.

2.7 Analysis and Interpretation of Results

This research involved different types of information and data, from different fields of research as well as use of a questionnaire and expert interviews. In order to organize these data, the research was structured around the existing frameworks from literature for the inventory of general MP sources as well as cruise facilities. In addition, the identified wastewater streams and related wastewater management practices were described in tabular form. These frameworks were then combined into matrices in order to structure the available information and to ensure that all relevant topics were covered through crosschecking. This structure guided the more detailed part of the research, and in particular the identification of cruise-specific MP sources. Where scientific literature was lacking, secondary resources were considered.

3.1 Literature Review of Microplastic Sources

Tables 1 , 2 present the overview of main source groups of primary and secondary MPs in the marine environment, modified from Lassen et al. (2015) , and extended with the results from other studies (indicated in the table, where applicable). The column on the right indicates whether the listed source groups were considered relevant for cruise ship wastewater. MP sources that were not considered relevant include raw materials for plastic production, industrial and professional handling processes of plastics, emissions from road traffic (tires, brake pads, bitumen and road paint), agricultural, aquaculture and oil and gas applications, typical onshore waste management issues (illegal waste burning, landfills and dumps), as well as the fragmentation of macroplastics in the environment due to natural processes. Also, the blasting of the ship hull during large scale maintenance with plastic abrasives is not further considered as blasting is not part of normal ship operations. Furthermore, Lassen et al. (2015) includes a separate category of primary MP emissions from paints through the washing of brushes. This source group was not considered applicable to cruise ships since this is mainly relevant for “do it yourself” and not for industrial practices ( Verschoor et al., 2016 ). The category other includes plastic beads used in professional dish washing machines, plastic beads and ironing beads used by children, printer toner, specialty chemicals in wastewater treatment facilities ( Scudo et al., 2017 ) and oil and gas industry ( Sundt et al., 2014 ).

Table 1 Generic primary MP sources, modified from ( Lassen et al., 2015 ) and indicating relevance to cruise ships.

Table 2 Generic secondary MP sources, modified from ( Lassen et al., 2015 ) with descriptions and relevance to cruise ships. .

3.2 Cruise-Specific Functionalities

3.2.1 facilities.

Tables 3 and 4 give an overview of the typical hotel facilities and ship facilities as present on contemporary cruise ships, based on Lois et al. (2004) . The overview is not exhaustive and may not be representative for all cruise ships but is indicative of the main systems and facilities present on ships, with the purpose to identify potential sources of MPs throughout the vessel.

Table 3 Hotel facilities on board cruise ships [adapted from Lois et al. (2004) ].

Table 4 Ship facilities on board cruise ships [adapted from Lois et al. (2004)] .

3.2.2 Stores

Cruise ships carry stores of various types. Such stores include fuel and ship maintenance products for ship operations as well as food, potable water and detergents for hotel operations. Véronneau and Roy (2009) distinguish the following main purchasing streams of cruise ships: fuel, corporate, technical and hotel purchasing. Fuel purchasing covers fuel and other petroleum products for daily consumption, such as lubricants. Corporate items relate to office related materials such as office supplies and computers. Technical items include items for facility and ship maintenance, e.g. engine parts, electronic components and carpeting materials. Consumable items and food required for hotel operations fall under the category of hotel purchasing. Furthermore, fresh water is a key resource on board.

3.2.3 People

Passengers and crew bring their personal belongings in their luggage. Significant categories are likely to include personal clothing, shoes, flipflops, personal toiletries and medication, electronics, books, suitcases and backpacks and snacks. People with children may bring plastic and inflatable toys. Furthermore, souvenirs bought ashore are brought on board after port visits.

3.3 Inventory of Sources and Release Mechanisms

Overviews of key MP sources and release mechanisms of both primary and secondary MPs on board cruise ships are displayed in Tables 5 and 6 . The categories from Lassen et al. (2015) were revised to reflect both the general categories as found in literature as well as the relevance of these categories for cruise operations.

Table 5 Primary microplastic sources and release mechanisms with relevance to cruise ship wastewater.

Table 6 Secondary microplastic release mechanisms and sources with relevance to cruise ship wastewater.

The main source groups for primary MPs ( Table 5 ) are personal care & cosmetics, cleaning & maintenance and medical & pharmaceutical. Potential release mechanisms are mainly related to the use of products in “wet” applications, e.g. rinse-off bath and shower products, spa treatments, wet cleaning, dish washing, laundry and wastewater treatment. Other release mechanisms include medication use, medical and dental treatments, printing and damage of user products that contain primary MPs, e.g. polystyrene pellets or beads. In addition, certain shipboard wastewater treatment systems use flocculants ( EPA, 2011 ; Chen et al., 2022 ), which could be polymer-based. The detailed assessment of cruise ship facilities led to the exclusion of rubber granules from artificial turfs as a source of primary MPs: no examples could be found of high impact sport facilities on board cruise ships that would require “third generation turfs” using a performance infill of (synthetic) rubber granules for shock absorption ( Hann et al., 2018 ).

The identified release mechanisms for secondary MPs ( Table 6 ) include the wear and damage of products during normal use, laundry and cleaning of textiles, wear and damage of painted surfaces, waste handling and littering. Sources embrace all plastic and synthetic items and surfaces on board the vessel, including paints and waste.

3.4 Linking Wastewater Streams to Microplastic Sources

The main wastewater streams that are produced on board cruise ships are sewage, grey water and oily bilge water. Sewage is the wastewater from toilets and primarily consists of human body wastes and water and may on some ships be mixed with wastes from medical facility sinks and drains ( EPA, 2008 ). The International Convention for the Prevention of Pollution from Ships (MARPOL) covers the international regulations for sewage in Annex IV of the convention. According to these regulations, sewage may be discharged overboard without treatment outside coastal zones, provided that the ship maintains a minimum sailing speed of 4 knots. The average sewage generation rate is estimated at 68 l/person/day ( Vicente-Cera et al., 2019a ). Grey water consists of the wastewater streams from shower and bath, accommodation sinks, laundry, dishwashers and galleys ( EPA, 2008 ). Wastewater from these sources is in practice often mixed with wastewater from other sources, such as drainage from drains and sinks in non-engine room spaces, food pulper effluents and wastewater from whirlpools ( EPA, 2008 ). Unlike sewage, grey water discharges are not internationally regulated. Vicente-Cera et al. (2019a) estimate the average generation rate throughout the industry at 160 l/person/day. EPA (2008) defines oily bilge water as “the mixture of water, oily fluids, lubricants, cleaning fluids, and other similar wastes that accumulate in the lowest part of a vessel from a variety of different sources including engines (and other parts of the propulsion system), piping, and other mechanical and operational sources found throughout the machinery spaces of a vessel”. International regulations, covered by MARPOL Annex I, allow discharges of oily bilge water at sea, provided that approved oil filtering equipment is used. The oil residue from the filtering process is to be stored in dedicated oil sludge tanks and delivered to port reception facilities (PRF). Vicente-Cera et al. (2019a) estimate that the average industry generation rate is 23 l per nautical mile.

In order to link the different wastewater streams to MP sources, the identified wastewater streams were divided into different sub-streams, each reflecting potential entry routes of MPs into wastewater. The left-hand side of Table 7 summarizes the main sub-streams of which the wastewater streams consist. On the right-hand side, the primary MP source categories (as listed in Table 5 ), as well as the typical types of secondary MPs of relevance to these (sub-)streams are listed.

Table 7 Linking cruise ship wastewater streams to pathways and microplastic sources.

The results demonstrate that the MP sources attributed to the different wastewater streams vary significantly. The MP content in sewage derives from pharmaceuticals and detergents used for the cleaning of toilets as well as larger items that are disposed in toilets. The MP sources related to grey water include personal care and cosmetic products (PCCP), detergents used for cleaning, dishwashing and laundry, fibers from synthetic textiles and the secondary MPs that are removed by wet cleaning. Finally, the MP sources attributed to oily bilge water mainly relate to engine room operations, which may involve various products for the cleaning, maintenance and operation of machinery that contain primary MPs. In addition, the different sub-streams of oily bilge water collect solid waste and dust, including plastics and secondary MPs, on their way to the bilges.

3.5 Wastewater Management

3.5.1 sewage and grey water.

There exist two categories of treatment systems that are relevant to sewage and grey water. Older ships are typically fitted with sewage treatment plants (STP), generally referred to as Marine Sanitation Devices (MSD), dedicated to the treatment of sewage. On these ships, grey water is typically not treated ( EPA, 2008 ). MSD must be approved by the flag state of the vessel and comply with local effluent standards, if available. EPA (2008) reports that conventional MSD on board cruise ships treat sewage through biological treatment and chlorination, while some systems combine maceration and chlorination. Advanced Wastewater Treatment Systems (AWTS) comprise a range of relatively new technologies for treating sewage more effectively than the older MSD. For these systems to function properly, the influent of sewage is typically not sufficient. Thereto, (part of) the grey water streams are also routed through the AWTS. The use of these systems is becoming the standard in the cruise industry ( King County, 2007 ) and newbuilds are typically fitted with such systems ( Nuka Research, 2019 ). From the 2021 Cruise Report Card, published by Friends of the Earth 6 and covering the 18 major cruise lines and 202 ships, it can be derived that 75% of the cruise ships have an AWTS. According to Vard (2018) , most AWTS on board cruise ships are of the Membrane Bioreactor (MBR) type, utilizing an activated sludge process in combination with membrane filtration. Systems of the Moving Bed BioReactor (MBBR) type consist of a bioreactor filled with plastic beads, supporting bacterial growth, in combination with a Dissolved Air Flotation (DAF) unit ( Huhta et al., 2007 ). No complete overview could be retrieved of systems that are in use throughout the industry. However, the Alaska Department of Environmental Conservation annually reports which large cruise ships operated in Alaskan waters and which type of treatment system is used on board these ships. Table 8 provides an overview of the different systems that were used on board the ships that operated in Alaskan waters in 2019 ( ADEC, 2019 ), and indicates the number of ships associated with each system. Further information about these systems was collected from the AWTS brand websites, as well as ship-specific implementations, and added to the table. It follows that 18 out of 24 ships had an MBR type of AWTS, and 14 of these were of the brand Hamworthy. Six vessels operated an MBBR type AWTS of which 5 were of the brand Scanship.

Table 8 Overview of characteristics of AWTS systems and processes on cruise ships operating in Alaskan waters during 2019.

The MBR systems all involve a pre-treatment filtering of the influent to remove coarse solids and prevent blocking of the membranes. The treatment itself involves the biological oxidation through an activated sludge process and ultrafiltration through membranes, where concentrates are generally fed back to the bioreactors and filtered effluents are collected in a permeate tank. The MBBR influents also pass filters to remove coarse solids. In the reactor, biological matter is removed through aerobic biological oxidation, and consequently DAF units separate particulate matter. Finally, the effluents pass polishing filters. All systems utilize UV disinfection to remove pathogens. Where available, mesh sizes of screens and filters are included. Since MBR systems are based on ultrafiltration, the mesh of the membranes is very fine with pore sizes below 100 nm.

Both grey water and sewage could be discharged to the marine environment without treatment. This applies to grey water for ships which do not have AWTS and ships which route only certain grey water streams through AWTS. Furthermore, it is possible that treatment systems are switched off at open sea, resulting in discharges of raw sewage and grey water. In 2021, 25% of the cruise fleet had no AWTS in place and thus discharged untreated grey water to the marine environment. Since these would typically concern older, and smaller cruise ships, the percentage of total grey water discharged through this route is likely smaller and this is expected to decrease in the future due to the increased use of AWTS. The MARPOL Convention allows the discharge of untreated grey water and, under certain conditions, sewage outside coastal zones. So theoretically, treatment systems could be switched off when the ship is on open seas. An EPA survey of four cruise ships fitted with AWTS reports that all vessels operate the system on a continuous basis ( EPA, 2006a ; EPA, 2006b ; EPA, 2006c ; EPA, 2006d ) and therefore do not discharge raw sewage. This is in line with the CLIA waste management policy, which prohibits the discharge of untreated sewage on board member cruise lines 9 . One of the ships in the EPA survey ( EPA, 2006b ) only routes the grey water from accommodations to the AWTS and discharges galley and laundry wastewater overboard without treatment, demonstrating that discharges of untreated grey water also occur on vessels with AWTS. AWTS and MSD filtering and treatment processes separate the wastewater into treated effluents and waste products. Sewage is typically high in solids, such as toilet paper and sanitary items, which is removed before sewage enters the treatment system, leaving screening solids of various sizes in the sieves and membranes. Another waste stream is the formation of biosludge. Biosludge or excess biomass consists of organic material as well as bacteria, resulting from the biological consumption of sewage ( EPA, 2008 ) and contains over 95% water ( Avellaneda et al., 2011 ). It is separated from the treated effluents by filtration ( EPA, 2008 ) and therefore would contain any solids such as MPs that have entered the bioreactor.

Literature provides some information on the disposal of waste products from cruise ship sewage and grey water treatment. Disposal options are incineration on board, landing at PRF and discharge at open sea ( EPA, 2008 ; Klein, 2009 ; Avellaneda et al., 2011 ). The relevant findings from an EPA survey of four cruise ships with AWTS ( EPA, 2006a ; EPA, 2006b ; EPA, 2006c ; EPA, 2006d ) are shown in Table 9 , together with the details of a case study cruise ship, representing an average-sized cruise ship operating in the Caribbean, as described by Kotrikla et al. (2021) . From this table it follows that three out of five ships discharge biosludge overboard. One of these ships also discharges the screening solids from the laundry and accommodation wastewater treatment system overboard, whilst solids from sewage are collected and incinerated on board. These data are in line with Klein (2009) who reports the overboard discharge of waste biosludge by 15 out of 16 ships in Washington State waters, with dewatering and incineration of biosludge on board one ship. Experts interviewed as part of this research stated that delivery of biosludge to PRF is currently not a common method on a worldwide scale as adequate facilities are lacking. This is also outlined by Avellaneda et al. (2011) who raise the logistic challenges of dealing with the large amounts of biosludge from cruise ships in ports without fixed reception facilities, rendering this scenario unrealistic. The available data indicates that for screening solids, incineration or delivery at PRF is more common.

Table 9 Sewage sludge treatment and disposal on board four cruise ships ( EPA, 2006a ) ( EPA, 2006b ) ( EPA, 2006c ) ( EPA, 2006d ).

3.5.2 Oily Bilge Water

As international regulations prohibit the discharge of untreated bilge water, there are two main methods used for the disposal of oily bilge waters: storage on board and delivery to onshore facilities, and onboard treatment. The treatment of bilge water is aimed at separating the oily constituents and water, such that the treated bilge water can be discharged overboard and the oily constituents are retained on board in sludge tanks for delivery to shoreside facilities ( EPA, 2011 ). The systems used for the treatment of oily bilge waters are generally referred to as Oily Water Separators (OWS). EPA (2011) reports that contemporary OWS are comprised of a series of different separation methods and that all of the OWS systems for bilge waters that are approved by the US Coast Guard are a combination of gravity-based separation and one or more forms of polishing treatment. Oil and other contaminants that are contained from the bilge water are collected in sludge tanks. This oily sludge may be stored on board for discharge at shore reception facilities or incineration on board. Table 10 summarizes representative options for wastewater treatment and the discharge and disposal of the resulting effluents and waste products.

Table 10 Summary of identified representative wastewater management options per wastewater stream.

3.6 Cruise Line Questionnaire

Since the questionnaire was distributed almost simultaneous with the first infections of COVID-19 on board cruise ships, the response was minimal. One CLIA member company responded and completed the questionnaire. However, with a fleet size of over 15 vessels, the responding company can be considered an important player in the industry and generally representative.

All ships of this company have holding tanks and MSD or AWTS systems for the treatment of sewage and grey water, with most ships having AWTS. In the case of MSD, grey water is stored on board and discharged at a minimum distance of 12 nautical miles from the nearest land. All ships are equipped with OWS for the treatment of oily bilge water, and also fitted with holding tanks for discharge at PRF when necessary.

All MSD operated by the company are using biological treatment in combination with chlorination. The screening solids captured by the treatment process are incinerated on board. The MSD are operated on a continuous basis. When the ships operate within 12 nautical miles from nearest land, treated effluents are contained in storage tanks and discharged later.

Most AWTS installed are of the MBBR type, and some are MBR. All sewage, accommodation, laundry and dishwashing wastewater streams are routed through the AWTS. The systems are operated on a continuous basis and effluents are discharged at a minimum distance of 3 nautical miles from the nearest land, confirming commitment to the CLIA zero-discharge policy for untreated sewage. Biosludge is either discharged to sea, incinerated or landed at PRF, where the chosen method depends primarily on the region of operation. Screening solids are typically incinerated on board and ashes are delivered to PRF.

In terms of policies, the company reports the initiation of the phasing out of “discretionary single use plastics on our ships”. Additionally, onboard gift shops and spas do not sell products containing microbeads. No measures were reported regarding the use of synthetic textiles or the application of microfiber filters in laundry installations.

4 Discussion

This article explored for the first time the sources and pathways of MPs in cruise ship wastewater, using a novel approach, based on general literature on MP sources in the marine environment as well as literature and industry information on cruise operations and wastewater management practices on board cruise ships. An overview was presented of the main source groups and release mechanisms of primary and secondary MPs on board cruise ships. Pathways of MPs were identified by linking the identified sources to the main wastewater streams on board cruise ships and an assessment of typical wastewater management practices.

4.1 Inventory of Sources

An overview was presented of the main source groups of primary MPs on board cruise ships, each reflecting the types of products and operations that are relevant to MP releases: personal care & cosmetics, cleaning & maintenance, medical & pharmaceutical and miscellaneous. PCCP are generally considered a key source of MPs in onshore wastewater treatment plants (e.g. Carr et al. 2016 ; Mason et al. 2016 ). There is no reason to assume that this would not be the case on board cruise ships. Moreover, the use of sun protection products and presence of spa and beauty facilities could result in even higher loads. Both fragrances and UV-filters linked to PCCP have been detected in cruise ship wastewater ( Westhof et al., 2016 ; Vicente-Cera et al., 2019b ), with concentrations of fragrances at similar levels as those in onshore domestic wastewater and concentrations of UV-filters exceeding those ( Vicente-Cera et al., 2019b ). It should be noted that the data reported in the latter study were collected under maintenance conditions and could be an underestimate for normal operations with passengers on board. This suggests that cruise ship wastewaters contain concentrations of PCCP constituents that are similar or exceeding those of onshore wastewater. Several studies ( Sundt et al., 2014 ; Lassen et al., 2015 ; Magnusson et al., 2016 ) assessed medical and pharmaceutical products as a minor source of MPs to the environment. Both Westhof et al. (2016) and Vicente-Cera et al. (2019b) found concentrations of pharmaceutical compounds in cruise ship wastewater at similar levels compared to domestic wastewater, suggesting no substantial differences in their use on board cruise ships and on land.

Literature reports MPs and synthetic polymers in various products used for industrial cleaning and care. These include hard surface cleaners, toilet cleaners and blocks, stainless steel cleaners, bathroom acid cleaners, oven cleaners, laundry detergents and stain removers ( Scudo et al., 2017 ), commercial hand-cleaning products ( Lassen et al., 2015 ; Scudo et al., 2017 ) and synthetic waxes in floor agents ( Essen et al., 2015 ). Most of the listed product types could be relevant to cruise ships. However, no studies could be identified that address concentrations of detergents and other maintenance products in cruise ship wastewater, nor about the presence of MPs in products used for specific ship operations. Scudo et al. (2017) estimated that industrial hand-cleaning soaps used for the removal of grease, paints etc. account for more than half the tonnage of all applications of MPs in rinse-off products. Considering the nature of cruise ship operations, this could be an important source as well. In addition, considering the wide range of applications of MPs in industrial cleaning products, the use of MPs in specialty maritime and cruise cleaning and maintenance products cannot be ruled out.

The identified release mechanisms for secondary MPs include laundry, waste handling and littering as well as the general wear and tear of products, painted surfaces and other surfaces and facilities. The source products encompass a broad array of products and materials. Many of these concern facilities such as painted surfaces, furnishing and safety equipment, but also stores, e.g. disposable plastics, cleaning cloths and packaging materials and personal belongings. Whereas primary MPs in many cases are intentionally released directly to water during product use ( Boucher and Friot, 2017 ), secondary MPs mainly concern unintentional losses. These MPs may end up in wastewater, e.g. through wet cleaning, but could also be disposed of in solid waste or transported off the ship via air. As a result, not all MP sources may be equally relevant to wastewater. Laundry is an exception, as most of the microfibers released during laundry would be drained with laundry effluents to the grey water system. Synthetic textiles are considered a major source of MPs in the marine environment ( Carney Almroth., et al., 2018 ). Azizi et al. (2022) have summarized the findings of over 400 studies about MPs evaluation in conventional wastewater treatment plants on land. The authors concluded that, throughout the plants evaluated in these studies, fibers were most commonly found, with an average abundance of 57% fibers throughout the different treatment steps. The high contribution of fibers is commonly attributed to the washing of synthetic textiles (e.g. Browne et al., 2011 ; Napper and Thompson, 2016 ; Ziajahromi et al., 2017 ; Raju et al., 2018 ). Cruise ships have extensive laundry facilities for the washing, drying and folding of professional textiles and most ships also offer laundry services for guests and have launderettes for crew. On the Oasis of the Seas about 42,000 kg of laundry is processed on embarkation day 10 . This suggests that laundry may be a major source of MPs on board cruise ships, depending on the nature of professional textiles such as sheets, towels and crew uniforms. To which extent these MPs reach the grey water system also depends on the use of laundry filters, which could remove up to 78% of fibers ( Napper et al., 2020 ) and, as such, could substantially lower the concentration of microfibers in grey water. Many cruise lines have a policy in place, or have pledged to do so, to phase out certain single use plastics such as straws, stirrers and cups 11 , 12 , 13 , 14 , to reduce their plastic footprint. In line with this trend, cruise lines could consider the use of plastic-free or non-synthetic alternatives for the MP sources that are reported in this study. The majority of the primary MP sources relate to “stores”, indicating that these products are purchased on a regular basis by the cruise line. The company that was consulted in this study already stopped the sale of products containing microbeads in onboard shops. Such a policy could be further extended to also cover PCCP that are used throughout the ship (e.g. in bathrooms and spas) as well as cleaning & maintenance products, including industrial hand soaps. Secondary sources of MPs are more varied and also include permanent ship and hotel facilities, for which plastic-free alternatives are either unfeasible or excessively expensive. However, considering that laundry potentially is a major source of MPs in wastewater, measures addressing this specific source could be effective in order to minimize the total MP load in untreated wastewaters, for instance through replacing synthetic textiles with natural alternatives or the use of microfiber filters in laundry systems.

4.2 Pathways Through Wastewater

The results demonstrate that the MP sources attributed to the different wastewater streams vary significantly. The main sources related to sewage are pharmaceuticals, detergents and the disposal of larger plastic items in toilets. The sources related to grey water include PCCP, detergents, fibers from synthetic textiles and secondary MPs that are removed by wet cleaning. The sources attributed to oily bilge water mainly relate to engine room operations. The findings for sewage and grey water are in line with the findings of Westhof et al. (2016) , who evaluated the presence of different types of micropollutants in various wastewater streams on board a cruise ship. Their findings reveal a predominance of oral pharmaceutical residues in sewage with lower concentrations of other pollutants attributed to human excretion. In grey water the highest concentrations were found for caffeine, attributed to the draining of remaining coffee and residues to the grey water system, and flame retardants, which according to the authors diffused from the host material and were consequently discharged to wastewater via laundry, handwashing, bathing and showers. In addition, significant concentrations of pharmaceuticals, UV filters, fragrances and a plastic softener were found, indicating the relevance of PCCP, skin applied pharmaceuticals (e.g. salves) and laundry detergents for grey water.

This paper focused on MPs in the main wastewater streams on board cruise ships. Miscellaneous wastewater streams include ballast water, wastewater from pools, whirlpools and spas, food pulper effluents, effluents from sinks and drains, deck wash water and runoff, wash water from exhaust gas cleaning systems, cooling water, condensates as well as various types of operational wastewater from different types of equipment and machinery ( EPA, 2008 ; EPA, 2013 ; MEPC, 2017 ). These could also act as significant pathways of MPs. Ballast waters, for instance, have been reported to contain very high concentrations of MPs ( Matiddi et al., 2017 ). In order to assess the total contribution of MP pollution from cruise ship wastewater, these pathways should also be considered.

4.3 Wastewater Management

MPs in cruise ship wastewater may be discharged to the ocean through the discharge of both untreated and treated effluents, as well as through the overboard discharge of waste products from wastewater treatment.

The performance of wastewater treatment systems that are in use in the industry is not well documented due to a lack of administrative monitoring ( Westhof et al., 2016 ) and their effectiveness in retaining MPs in particular has not been comprehensively documented. EPA (2008) reports various pollutant concentrations in the effluents from various sampling efforts of AWTS and MSD effluents of cruise ships operating in USA waters between 2003 and 2005, with non-detected values for both settleable and suspended solids in most AWTS effluents. This indicates that the cruise ship AWTS included in the sampling efforts were generally effective in capturing solids. Furthermore, both membrane ultrafiltration, a main component of MBR systems, and DAF, a main component of MBBR systems, are associated with very high MP removal rates in onshore systems. For MBR and membrane ultrafiltration, rates reported in literature ( Talvitie et al., 2017a ; Lares et al., 2018 ; Ma et al., 2018 ; Lv et al., 2019 ) exceed 99% and this is considered the most effective technology to remove MPs in onshore WWTP (e.g. Sun et al., 2019 ). For DAF, values between 70% and 96% are reported ( Talvitie et al., 2017a ; Esfandiari and Mowla, 2021 ), for different types of flocculants and coagulants that are added during the process. On the other hand, EPA (2008) reports values of suspended solids in the effluents of cruise ship MSD systems which are substantially higher than the USA discharge standards for onshore wastewater treatment systems, indicating that these systems may be less effective in capturing MPs. No data could be retrieved regarding the effectiveness of OWS in capturing particulate matter. Onshore wastewater treatment plants are generally considered important sources of MPs in aquatic environment, despite their effectiveness in removing MPs from influents, due to the large volumes of wastewater that pass these plants [e.g. Talvitie et al. (2017b) ]. Considering the volumes of wastewater that are generated on board cruise ships, treated wastewater from cruise ships therefore represents a significant pathway.

The results of this study reveal that, currently, 25% of the world cruise fleet discharges all grey water without treatment to the ocean as these ships do not have AWTS. In addition, AWTS configurations not necessarily cover all grey water sub-streams and as a result, a potentially significant volume of grey water is discharged without treatment from ships with AWTS. Further study of typical configurations is required to assess the volumes and characteristics of such discharges throughout the industry.

Various studies of onshore wastewater treatment plants have investigated the fate of MPs in onshore wastewater treatment plants, demonstrating that the vast majority of MPs in the influent are captured in sludge ( Carr et al., 2016 ; Talvitie et al., 2017b ; Gies et al., 2018 ). Since sewage sludge is commonly recycled as fertilizer in agriculture applications ( Nizzetto et al., 2016 ), this represents a major pathway of MPs to the environment on land, leading to the accumulation of MPs in agricultural soils ( Corradini et al., 2019 ). Similarly, biosludge resulting from AWTS treatment on board cruise ships likely contains high concentrations of MPs, due to the expected effectiveness of MBR and DAF in capturing MPs. The results of this paper indicate that while three options for the disposal for biosludge are used throughout the industry, overboard discharge is the most common method. The overboard discharge of this substance therefore leads to a delayed and concentrated discharge of the MPs in grey water and sewage and this practice should be avoided. The development of adequate PRF for biosludge in cruise regions could be instrumental in reducing the volumes of MPs that are discharged through this pathway, especially in vulnerable areas receiving large numbers of cruise ships. The literature review as well as questionnaire response indicates that overboard discharge of screening solids is not common, however this practice has been reported for one ship by EPA (2006a) , indicating that this scenario cannot be ruled out.

In general, the available literature on wastewater treatment systems is restricted to a small number of dated reports (e.g. King County (2007) ; Huhta et al. (2007) ; EPA (2008) ; EPA (2011) , most of which were produced by USA government authorities. Furthermore, the available data regarding the practices of discharging untreated grey water and sewage as well as the overboard discharge of biosludge concern a limited number of isolated and largely dated case studies (e.g. EPA, 2006a ; EPA, 2006b ; EPA, 2006c ; EPA, 2006d ; Klein, 2009 ; Kotrikla et al., 2021 ). In order to address these knowledge gaps, this research collected information on both wastewater treatment systems and wastewater management practices from one large cruise line. The results confirm trends and practices in wastewater management as reported by other studies (see section 3.5.1). However, it should be noted that these efforts either build on voluntary contributions or on cruise operations in the USA, and Alaska in particular; an area that is more strictly regulated and monitored than the mainstream cruise regions in the Caribbean and Mediterranean. Therefore, these results are likely biased and caution should be taken when extrapolating these results to the industry as a whole, in particular in vulnerable areas with little regulation and/or inadequate enforcement. An industry-wide overview of wastewater management systems and practices, ideally linked to regions of operation, would greatly support the understanding of leakages of MPs and other pollutants from cruise ship wastewater.

Finally, as recently raised on one of the leading digital platforms in the maritime industry 15 , the improper management of solids in sewage may lead to discharges through other pathways, such as the disposal of any solids remaining in the holding tanks and the use of cutter pumps in the collection and treatment of sewage. These cutter pumps are purposely designed to remove the load on screens by breaking down solids in smaller particles. This is rendering screenings less effective, and even contributing to the formation and release of MPs to the environment. This further emphasizes the need for a holistic approach of wastewater management in order to prevent leakages of MPs.

4.4 Conclusions

This paper for the first time explored the sources and pathways of MPs in cruise ship wastewater, providing insight on the array of sources and pathways, highlighting priority areas for mitigation and identifying additional knowledge gaps. On the level of individual companies or ships, the overview of sources and pathways allows for the identification of mitigating measures from source-to-sea, by identifying the full array of sources and mechanisms that contribute to the release of MPs to wastewater, as well as the connections between sources and the different wastewater streams. As a result, it also provides guidance for purchasing policies by cruise lines and the need for ongoing education of crew and passengers.

In general, it is recommended that cruise lines consider the inclusion of PCCP well as cleaning and maintenance products containing primary MPs in their policies to phase out the use of single-use plastics. In addition, the replacement of professional synthetic textiles with non-synthetic alternatives and the use of laundry filters could be effective in reducing the MP load in wastewaters. Furthermore, adequate wastewater management is key to prevent MP leakages and reduce the MP load in wastewaters that are discharged to the ocean. This is greatly supported by the increased use of AWTS. However, the use of these systems is only a partial solution, which should be part of a holistic management of wastewater streams. Efforts should be made to minimize discharges through waste products, wastewater streams bypassing AWTS as well as wastewater streams other than discussed in this study. Although at the global scale, the quantitative contribution of MPs from cruise ship wastewater is small in comparison to land-based sources, local impacts could still be significant due to the large amounts of wastewater, waste products that are discharged without treatment, the vulnerability of the exposed coastal and marine ecosystems and the concentrated nature of cruise activities. To better place the problem in perspective, identify cost-effective measures and areas at risk, it is required that MP concentrations in different effluents and waste products are quantified through measurements and that contemporary wastewater management systems and practices throughout the industry are better understood.

In conclusion, the approach for this study was successful in exploring the major sources and pathways of MPs within the study scope, and to highlight knowledge gaps and starting points for mitigation. This makes it a valuable tool that could also be applied in other maritime sectors and will support global efforts to identify all sources and pathways of MPs within the context of the UNEA-5.2 resolution.

Data Availability Statement

The original contributions presented in the study are included in the article/supplementary material. Further inquiries can be directed to the corresponding author.

Author Contributions

The research was performed by MF and she also wrote the paper. CC and AL contributed by guiding the research, discussing ideas and supervising the writing of this paper. All authors contributed to the article and approved the submitted version.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s Note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Acknowledgments

The authors would like to thank Mr. G. Burnett of CLIA for distributing our questionnaire among the CLIA members and collecting their responses, as well as all experts who contributed to this research.

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Keywords: cruise ships, microplastics, wastewater, sea-based sources, marine litter, plastic pollution, marine pollution, shipping

Citation: Folbert MEF, Corbin C and Löhr AJ (2022) Sources and Leakages of Microplastics in Cruise Ship Wastewater. Front. Mar. Sci. 9:900047. doi: 10.3389/fmars.2022.900047

Received: 19 March 2022; Accepted: 28 April 2022; Published: 26 May 2022.

Reviewed by:

Copyright © 2022 Folbert, Corbin and Löhr. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Maartje E. F. Folbert, [email protected]

This article is part of the Research Topic

Plastics in Aquatic Systems: from Transport and Fate to Impacts and Management Perspectives

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Carnival Cruises to Pay $20 Million in Pollution and Cover-Up Case

By Sarah Mervosh

• June 4, 2019

In 2016, Princess Cruise Lines agreed to pay a $40 million penalty for illegally dumping oil-contaminated waste into the sea and acts by employees to try to cover it up.

It was the largest criminal penalty ever imposed for intentional vessel pollution, and the Justice Department put the cruise line’s parent company, Carnival Corporation, on notice.

But that did not stop the company from polluting again, according to federal prosecutors.

On Monday, Carnival and its Princess line acknowledged violating probation terms from the 2016 case and were ordered to pay an additional $20 million penalty, putting further pressure on the world’s largest cruise corporation.

The new violations included discharging plastic into waters in the Bahamas, falsifying records and interfering with court supervision of ships by sending in teams ahead of inspections to pre-empt environmental violations, according to the corporation’s agreement with the Justice Department.

“A corporation is responsible to its shareholders and board of directors to be profitable, but not by breaking the law and destroying the very environment in which it navigates for profit,” Ariana Fajardo Orshan, the United States attorney for the Southern District of Florida, said in a statement .

The agreement came after the federal judge overseeing the case, Patricia A. Seitz, expressed frustration with Carnival’s “repeat offenses” and even threatened to bar its cruise ships from docking at United States ports. She ordered the corporation’s top executives to appear in person at a court hearing on Monday in Miami.

“I do take responsibility for the problems we have,” the corporation’s chief executive, Arnold W. Donald, said at the hearing, according to The Miami Herald . “I am extremely disappointed that we’ve had them. I know you have reservations about our commitment and who we are. I want you to know we are fully committed.”

Vessel pollution is just one of the many human-caused hazards facing ocean life today. Ship traffic and noise can cause the death of sea creatures ; marine animals routinely turn up dead with plastic in their stomachs ; and rising sea temperatures, stemming from climate change caused by human activity, are destroying the framework of many ocean ecosystems .

For decades, cruise lines — including Carnival — have been closely watched for violations of environmental rules. And even the most efficient cruise ships can emit three to four times as much carbon dioxide per passenger-mile as an airplane jet can.

Carnival, based in Miami, is a global operation that has a strong hold on the cruise market. In addition to Princess, its cruise lines include Carnival Cruise Line, Holland America Line and Seabourn. Together, the various brands serve about 11 million travelers each year, about 50 percent of the global cruise market, according to the company’s website .

Carnival’s stock market value is estimated to be nearly $35 billion.

In 2002, Carnival was ordered to pay $18 million in fines after pleading guilty to criminal charges related to falsifying records of oil-contaminated bilge water that six of its ships had dumped into the sea.

The company came under additional scrutiny after Princess agreed, in 2016, to plead guilty to felony charges and pay the hefty $40 million penalty.

In that case, prosecutors said that employees of one of the company’s cruise ships, the Caribbean Princess, had used several means, including a device called a magic pipe, to circumvent water-cleaning mechanisms and digital devices monitoring oil levels. Officials said that four other Princess ships had also been found to have engaged in illegal practices to discharge waste.

The discharged waste included gray water — water that has been contaminated with food particles, grease and fat — and water found in the ship’s bilge, the bottom part of the ship where oil waste from engines can accumulate.

A whistleblower employee alerted the authorities and certain engineers ordered a coverup, including directing subordinates to lie, according to prosecutors.

One motive for the dumping, officials said, was to save money, because removing the waste from the ship at ports is expensive.

As part of the deal, Princess was put on probation for five years, and other Carnival cruise ship companies were subject to audits and oversight. During the first two years of monitoring, officials found “numerous violations,” from pollution to deception, according to federal prosecutors.

During an audit of the cruise ship Carnival Elation in December, for example, officials found that food waste had been mixed with plastic straws, aluminum and other miscellaneous items, which were “ready to be discharged down the chute and then overboard while at sea,” records show.

Federal prosecutors argued that the episode was representative of a widespread problem of plastic dumping involving many ships, over many years, “despite full knowledge that such discharges are illegal and extremely harmful to the environment and marine life.”

Carnival has said it is making changes, including a commitment to reducing its plastic use. For example, it said it would eliminate drinking straws, except for in frozen drinks, which would be served with an edible straw. It also said rooms and spas would offer shampoo and conditioner in pump-top bottles, mirroring a trend in the hotel industry away from single-use toiletries .

“Carnival Corporation remains committed to environmental excellence and protecting the environment in which we live, work, and travel,” the company said on Monday in a statement . “Our aspiration is to leave the places we touch even better than when we first arrived.”

According to the court agreement, the company, which remains on probation for three more years, must also create a plan and make changes to its corporate structure. If it fails to meet certain deadlines by the fall, it could be forced to pay up to $10 million per day.

Follow Sarah Mervosh on Twitter: @smervosh .

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Carnival is cleaning up its act with better cruise fuel, waste reduction

As the world experiences record-setting temperatures this summer, and wildfires rage through several countries, global warming and the environment are top-of-mind issues for many.

The cruise industry often comes under fire for everything from its emissions to the level of food waste that occurs onboard ships. Historically, many vessels have also committed infractions like illegal dumping of trash, oil and gray water -- dirty (non-sewage) water from showers, sinks and laundry facilities.

One of the biggest offenders has been Carnival Corp., the company that operates several popular brands, such as Carnival Cruise Line, Princess Cruises, Holland America Line and Cunard Line -- all of which have been guilty of one or more of the above.

For more cruise news, reviews and tips, sign up for TPG's cruise newsletter .

Although Carnival Corp. is still on probation following several violations for which it was fined tens of millions of dollars, the environmental advancements Carnival Cruise Line has made on its newest ship, Mardi Gras, are impressive.

Upon its debut, the vessel became the first in North America with the capability to run on liquefied natural gas (LNG), a cleaner-burning fuel that greatly reduces sulfur and nitrogen oxide emissions as well as particulates, and also cuts down on greenhouse emissions.

Reducing harm to air and marine life

During my recent sailing on Mardi Gras , I went on a tour of the ship's engine control center, recycling facility and engine room with Richard Pruitt, Carnival Cruise Line's vice president of environmental operations.

Pruitt explained that the ship, which is a diesel/LNG-electric hybrid (meaning that it runs on a combination of the two) is more efficient than a vessel that runs on one or the other because it allows the ship's engineers to match the amount of energy produced by the engines to the amount of energy needed to run the vessel without worrying that there won't be enough (which would cause a blackout) or that there's too much (which would create waste).

Pruitt said the engines produce power that goes into a system that apportions energy to whichever onboard systems need it -- propulsion, air-conditioning, galleys, laundry, staterooms and more.

Although the engines can run on either LNG or diesel fuel, LNG was being used on my voyage. But that doesn't mean there isn't still a small bit of diesel needed.

"The ship has three large tanks for LNG and several tanks for what we call marine gas oil [MGO], which is similar to diesel that you see in an airplane or that you might even have in a truck or a car on the road," Pruitt said. "It's highly refined. [The ship] can run on either one. In fact, when the ship is running on LNG, we actually inject a very small amount of MGO into the cylinders because LNG [is so cold -- 250 degrees below zero, Fahrenheit -- that it] can't ... self-ignite.... So we have to spray a little bit of MGO into each cylinder. It's effectively the spark plug for getting the LNG to ignite and combust."

The ship, Pruitt said, can run for about two weeks on LNG when the tanks are full, but fill-ups happen more frequently for operational and safety reasons.

Dynamic positioning

Dynamic positioning, a system that allows a vessel to stay in place using thrusters and GPS coordinates, has been around for a while, but it's only recently that we've begun to hear about it on cruise ships.

The benefit of this technology is that it keeps a ship in one place without the use of anchors, which can cause significant damage to seabeds that are home to marine life.

Mardi Gras is certainly not the first vessel to operate using it, but it's important to note it as part of Carnival's overall effort to be more environmentally friendly.

Waste reduction and management

Single-use items.

Several years ago, nearly all mainstream cruise lines made a push to eliminate single-use plastics from their ships. These included everything from plastic bags in retail shops and drinking straws (which have been replaced with paper and even sugar straws on Carnival vessels) to single-serve condiment packets, coffee stirrers and, on some ships, even bottled water in plastic containers. But Pruitt says it's about more than that.

"If you don't generate it to begin with, then you don't have to handle it; you don't have to dispose of it," Pruitt said. "We've reduced a lot of single-use items. You hear a lot about single-use plastics, but it's really more than plastics. It's everything.

"You'll notice things like [single-use] butter pats are no longer on the ship. We've gone with small, little dishes with butter in it. Bulk sugar: We went from 100 million sugar packets [in the last full year of guest operations] down to where we just have sweeteners [in packets and sugar in larger refillable containers placed on tables].... You'll notice we don't have stirrers in the coffee bars anymore. You just get a spoon.... You'll notice also we've got bulk dispensers for cereal, rather than the little boxes."

The line has also reduced paper waste by providing lists of spa treatments, shore excursions and each day's FunTimes daily activities on its Hub mobile app, rather than as physical printouts. (Paper copies of the FunTimes are still available at the front desk on request.)

Recycling is another crucial component of most ships' onboard environmental efforts. Great care goes into sorting the contents of every trashcan that's emptied, whether it's from the galley or your stateroom.

An entire team of workers separates plastic, glass, metal and cardboard so it can be offloaded and properly processed in port.

Recycling is one of the most basic green initiatives undertaken by cruise lines in the past couple of decades. It's now a standard practice onboard modern passenger vessels, but Carnival even goes so far as to donate items like unwanted bedding, kitchenware, furniture and small appliances to shoreside charities instead of throwing them into landfills.

"We obviously generate a lot of food waste..." Pruitt admitted. "So we decided we wanted to try to address this, and we've done a couple things. We have a corporatewide food waste reduction. The last time we had guests onboard for a full quarter, we had achieved a 20% reduction, corporatewide, from where we had our baseline."

The main way Carnival Cruise Line accomplished the reduction was by slightly tweaking the portion sizes in its restaurants.

"It should be invisible to you," Pruitt said. "It shouldn't feel like 'oh, they're being stingy with my food.' But they've made adjustments; they've made improvements in [galley food] prep. We have a program that's called 'don't waste your waste,' where we're trying to minimize prep waste. It's like being thrifty at home. If you're chopping something up, 'oh, that could go in a soup,' so a lot of work has gone into that. We're very careful about first in, first out, trying to avoid spoilage ... because that all counts against us when it comes to food waste."

On our Mardi Gras sailing, Pruitt said the average food waste per person, per day, was 2.3 pounds.

"Food waste either gets landed [taken ashore for disposal], or it's chopped up, pulped up, and discharged at sea when we're outside of 12 nautical miles [from land]."

As a way to further reduce the amount of food waste discharged, Pruitt said the line implemented some additional technology, including what he refers to as a "stainless steel stomach," which aerates the food and introduces beneficial bacteria to break it down to a liquid form that's only a fraction of the original waste's volume. (Carnival Cruise Line is currently the only mainstream line using this type of system onboard.)

"Effectively, what you have in there is some media; we add in beneficial organisms that basically digest the food waste inside the tank," Pruitt said. "We're ... committed to installing these things throughout our fleet.... We're [already] at around 190-ish.... I've got two teams out there installing these things as we speak. This ship has 14."

"What we put in here is anything that can be digested," Pruitt said. "So, I'm not going to put in an oyster shell. I'm not going to put in a lobster shell. I'm not going to put in a heavily calcified beef bone or something in there because it might eventually break it down, but it would take up space. So if you put in there fruits and vegetables and meat and carbohydrates ... it will eat it down to where there's effectively just a liquid.... I've seen it where the [liquid] is fairly clear to where it can be a little bit thicker, like a bisque."

The machine models vary, but they have the ability to eat anywhere from 600 to 2,400 pounds of food waste per day, depending on their size. Pruitt monitors them with an app that allows him to see their progress and report any faults to an onboard engineer.

Pruitt also mentioned that Carnival might explore other food waste reducers, including dehydrators, which are used by some other cruise lines.

Water treatment and consumption

Pruitt said each person on Mardi Gras is responsible for about 50 to 60 gallons of water use per day. That includes everything from showering and brushing teeth to galley usage in order to prepare the meals each person consumes.

"On land, the typical American uses about 100 gallons a day," Pruitt said. "So, through water conservation measures, we save a lot of water onboard, and that's important because water is an energy issue for us.... We have to use energy to treat it."

"[On] Mardi Gras, like all of Carnival's ships going back to the Vista Class..., we've installed advanced wastewater treatment systems onboard. These treat all of the gray water and all of the black water to standards that are as good [as] or better than how most municipalities treat wastewater in the United States."

All water that comes from the ships' galleys is run through a grease separator to remove any grease, oil and other grill-related substances that could be harmful to the environment. The grease is then put into drums. (The ship also has an oil separator that uses centrifugal force to separate oil from water, based on their weight difference.)

All black water -- water that contains sewage -- goes through a pre-screen to remove toilet paper, feminine products, condoms and other debris that might be flushed down the toilet. In some cases, it's landed; in others, it's incinerated right onboard the ship.

After the black water is pretreated and the gray water is stripped of grease, they're combined in a mixing tank, where they undergo a series of processes to remove further solids as they rise to the top. Beneficial bacteria are then introduced to eat the solid matter.

Finally, ultraviolet light is used to disinfect the water, killing both good and bad bacteria and making it clean enough to discharge while docked (assuming the correct permits are in place). Onboard engineers are in charge of periodically testing the wastewater to make sure the processes are working.

Separate processes involving filtration and UV light are also used to treat bilge water (water that ends up in the lowest part of the ship due to leaking pipes or condensation) and ballast water (water used to make the ship heavier as potable water is consumed or to stabilize a ship to prevent listing).

Although chlorine is required to be used in pool and potable water, it is not used in wastewater. Potable water is taken onboard and goes through a reverse osmosis process in order to make it clean enough for drinking.

Power consumption

Many newer cruise ships have taken to using keycard-activated lighting in staterooms. In order for the lights to turn on, passengers must put a card into the slot near the cabin door.

Although Mardi Gras has them -- and they're worth mentioning as part of the big picture onboard -- they aren't new. In fact, they've been in operation for years, largely on European ships, but they have slowly begun to make their way over to vessels sailing from North America.

Carnival's newest ships will continue to follow along this greener path. The next vessel due to launch is Carnival Celebration, slated to debut in November 2022.

Cruise Ship Pollution: Background, Laws and Regulations, and Key Issues

July 2, 2004 – December 15, 2010 RL32450

The cruise industry is a significant and growing contributor to the U.S. economy, providing more than $32 billion in benefits annually and generating more than 330,000 U.S. jobs, but also making the environmental impacts of its activities an issue to many. Although cruise ships represent a small fraction of the entire shipping industry worldwide, public attention to their environmental impacts comes in part from the fact that cruise ships are highly visible and in part because of the industry’s desire to promote a positive image.

Cruise ships carrying several thousand passengers and crew have been compared to “floating cities,” and the volume of wastes that they produce is comparably large, consisting of sewage; wastewater from sinks, showers, and galleys (graywater); hazardous wastes; solid waste; oily bilge water; ballast water; and air pollution. The waste streams generated by cruise ships are governed by a number of international protocols (especially MARPOL) and U.S. domestic laws (including the Clean Water Act and the Act to Prevent Pollution from Ships), regulations, and standards, but there is no single law or rule. Some cruise ship waste streams appear to be well regulated, such as solid wastes (garbage and plastics) and bilge water. But there is overlap of some areas, and there are gaps in others. Some, such as graywater and ballast water, are not regulated (except in the Great Lakes), and concern is increasing about the impacts of these discharges on public health and the environment. In other areas, regulations apply, but critics argue that they are not stringent enough to address the problem—for example, with respect to standards for sewage discharges. Environmental advocates have raised concerns about the adequacy of existing laws for managing these wastes, and they contend that enforcement is weak.

In 2000, Congress enacted legislation restricting cruise ship discharges in U.S. navigable waters within the state of Alaska. California, Alaska, and Maine have enacted state-specific laws concerning cruise ship pollution, and a few other states have entered into voluntary agreements with industry to address management of cruise ship discharges. Meanwhile, the cruise industry has voluntarily undertaken initiatives to improve pollution prevention, by adopting waste management guidelines and procedures and researching new technologies. Concerns about cruise ship pollution raise issues for Congress in three broad areas: adequacy of laws and regulations, research needs, and oversight and enforcement of existing requirements. Legislation to regulate cruise ship discharges of sewage, graywater, and bilge water nationally was introduced in the 111th Congress (H.R. 3888 and S. 1820), but no legislative activity occurred on either bill.

This report describes the several types of waste streams that cruise ships may discharge and emit. It identifies the complex body of international and domestic laws that address pollution from cruise ships. It then describes federal and state legislative activity concerning cruise ships in Alaskan waters and activities in a few other states, as well as current industry initiatives to manage cruise ship pollution. Issues for Congress are discussed.

Topic areas

Economic Policy

Introduction

Cruise ship waste streams, applicable laws and regulations, international legal regime, domestic laws and regulations, solid waste, hazardous waste, bilge water, ballast water, air pollution, considerations of geographic jurisdiction, alaskan activities, federal legislation, alaska state legislation and initiatives, other state activities, industry initiatives, issues for congress, laws and regulations, oversight and enforcement.

The cruise industry is a significant and growing contributor to the U.S. economy, providing more than $32 billion in benefits annually and generating more than 330,000 U.S. jobs, but also making the environmental impacts of its activities an issue to many. Although cruise ships represent a small fraction of the entire shipping industry worldwide, public attention to their environmental impacts comes in part from the fact that cruise ships are highly visible and in part because of the industry's desire to promote a positive image.

Cruise ships carrying several thousand passengers and crew have been compared to "floating cities," and the volume of wastes that they produce is comparably large, consisting of sewage; wastewater from sinks, showers, and galleys (graywater); hazardous wastes; solid waste; oily bilge water; ballast water; and air pollution. The waste streams generated by cruise ships are governed by a number of international protocols (especially MARPOL) and U.S. domestic laws (including the Clean Water Act and the Act to Prevent Pollution from Ships), regulations, and standards, but there is no single law or rule. Some cruise ship waste streams appear to be well regulated, such as solid wastes (garbage and plastics) and bilge water. But there is overlap of some areas, and there are gaps in others. Some, such as graywater and ballast water, are not regulated (except in the Great Lakes), and concern is increasing about the impacts of these discharges on public health and the environment. In other areas, regulations apply, but critics argue that they are not stringent enough to address the problem—for example, with respect to standards for sewage discharges. Environmental advocates have raised concerns about the adequacy of existing laws for managing these wastes, and they contend that enforcement is weak.

In 2000, Congress enacted legislation restricting cruise ship discharges in U.S. navigable waters within the state of Alaska. California, Alaska, and Maine have enacted state-specific laws concerning cruise ship pollution, and a few other states have entered into voluntary agreements with industry to address management of cruise ship discharges. Meanwhile, the cruise industry has voluntarily undertaken initiatives to improve pollution prevention, by adopting waste management guidelines and procedures and researching new technologies. Concerns about cruise ship pollution raise issues for Congress in three broad areas: adequacy of laws and regulations, research needs, and oversight and enforcement of existing requirements. Legislation to regulate cruise ship discharges of sewage, graywater, and bilge water nationally was introduced in the 111 th Congress ( H.R. 3888 and S. 1820 ), but no legislative activity occurred on either bill.

More than 53,000 commercial vessels—tankers, bulk carriers, container ships, barges, and passenger ships—travel the oceans and other waters of the world, carrying cargo and passengers for commerce, transport, and recreation. Their activities are regulated and scrutinized in a number of respects by international protocols and U.S. domestic laws, including those designed to protect against discharges of pollutants that could harm marine resources, other parts of the ambient environment, and human health. However, there are overlaps of some requirements, gaps in other areas, geographic differences in jurisdiction based on differing definitions, and questions about the adequacy of enforcement.

Public attention to the environmental impacts of the maritime industry has been especially focused on the cruise industry, in part because its ships are highly visible and in part because of the industry's desire to promote a positive image. It represents a relatively small fraction of the entire shipping industry worldwide. As of October 2010, passenger ships (which include cruise ships and ferries) composed about 13% of the world shipping fleet. 1 The cruise industry is a significant and growing contributor to the U.S. economy, providing $40 billion in total benefits in 2009 and generating more than 357,000 U.S. jobs, 2 but also making the environmental impacts of its activities an issue to many. Since 1990, the average annual growth rate in the number of cruise passengers worldwide has been 7.4%, and in 2010, cruises hosted an estimated 14.3 million passengers. The worldwide cruise ship fleet consists of more than 230 ships, and the majority are foreign-flagged, with Liberia and Panama being the most popular flag countries. 3 Foreign-flag cruise vessels owned by six companies account for nearly 95% of passenger ships operating in U.S. waters. Each year, the industry adds new ships to the total fleet, vessels that are bigger, more elaborate and luxurious, and that carry larger numbers of passengers and crew. Over the past two decades, the average ship size has been increasing at the rate of roughly 90 feet every five years. The average ship entering the market from 2008 to 2011 will be more than 1,050 feet long and will weigh more than 130,000 tons. 4

To the cruise ship industry, a key issue is demonstrating to the public that cruising is safe and healthy for passengers and the tourist communities that are visited by their ships. Cruise ships carrying several thousand passengers and crew have been compared to "floating cities," in part because the volume of wastes produced and requiring disposal is greater than that of many small cities on land. During a typical one-week voyage, a large cruise ship (with 3,000 passengers and crew) is estimated to generate 210,000 gallons of sewage; 1 million gallons of graywater (wastewater from sinks, showers, and laundries); more than 130 gallons of hazardous wastes; 8 tons of solid waste; and 25,000 gallons of oily bilge water. 5 Those wastes, if not properly treated and disposed of, can pose risks to human health, welfare, and the environment. Environmental advocates have raised concerns about the adequacy of existing laws for managing these wastes, and suggest that enforcement of existing laws is weak.

A 2000 General Accounting Office (GAO) report focused attention on problems of cruise vessel compliance with environmental requirements. 6 GAO found that between 1993 and 1998, foreign-flag cruise ships were involved in 87 confirmed illegal discharge cases in U.S. waters. A few of the cases included multiple illegal discharge incidents occurring over the six-year period. GAO reviewed three major waste streams (solids, hazardous chemicals, and oily bilge water) and concluded that 83% of the cases involved discharges of oil or oil-based products, the volumes of which ranged from a few drops to hundreds of gallons. The balance of the cases involved discharges of plastic or garbage. GAO judged that 72% of the illegal discharges were accidental, 15% were intentional, and 13% could not be determined. The 87 cruise ship cases represented 4% of the 2,400 illegal discharge cases by foreign-flag ships (including tankers, cargo ships and other commercial vessels, as well as cruise ships) confirmed during the six years studied by GAO. Although cruise ships operating in U.S. waters have been involved in a relatively small number of pollution cases, GAO said, several have been widely publicized and have led to criminal prosecutions and multimillion-dollar fines.

In 2000, a coalition of 53 environmental advocacy groups petitioned the Environmental Protection Agency (EPA) to take regulatory action to address pollution by cruise ships. 7 The petition called for an investigation of wastewater, oil, and solid waste discharges from cruise ships. In response, EPA agreed to study cruise ship discharges and waste management approaches. As part of that effort, in 2000 EPA issued a background document with preliminary information and recommendations for further assessment through data collection and public information hearings. 8 Subsequently, in December 2008, the agency released a cruise ship discharge assessment report as part of its response to the petition. This report summarized information on cruise ship waste streams and findings of recent data collection activities (especially from cruise ships operating in Alaskan waters). It also identified options to address ship discharges. 9

This report presents information on issues related to cruise ship pollution. It begins by describing the several types of waste streams and contaminants that cruise ships may generate and release. It identifies the complex body of international and domestic laws that address pollution from cruise ships, as there is no single law in this area. Some wastes are covered by international standards, some are subject to U.S. law, and for some there are gaps in law, regulation, or possibly both. The report then describes federal and state legislative activity concerning cruise ships in Alaskan waters and activities in a few other states. Cruise ship companies have taken a number of steps to prevent illegal waste discharges and have adopted waste management plans and practices to improve their environmental operations. Environmental critics acknowledge these initiatives, even as they have petitioned the federal government to strengthen existing regulation of cruise ship wastes. Environmental groups endorsed legislation in the 109 th and 110 th Congresses (the Clean Cruise Ship Act) that would require stricter standards to control wastewater and other discharges from cruise ships. Similar legislation was introduced in the 111 th Congress (the Clean Cruise Ship Act, H.R. 3888 and S. 1820 ), but no legislative action occurred.

Cruise ships generate a number of waste streams that can result in discharges to the marine environment, including sewage, graywater, hazardous wastes, oily bilge water, ballast water, and solid waste. They also emit air pollutants to the air and water. These wastes, if not properly treated and disposed of, can be a significant source of pathogens, nutrients, and toxic substances with the potential to threaten human health and damage aquatic life. It is important, however, to keep these discharges in some perspective, because cruise ships represent a small—although highly visible—portion of the entire international shipping industry, and the waste streams described here are not unique to cruise ships. However, particular types of wastes, such as sewage, graywater, and solid waste, may be of greater concern for cruise ships relative to other seagoing vessels, because of the large numbers of passengers and crew that cruise ships carry and the large volumes of wastes that they produce. Further, because cruise ships tend to concentrate their activities in specific coastal areas and visit the same ports repeatedly (especially Florida, California, New York, Galveston, Seattle, and the waters of Alaska), their cumulative impact on a local scale could be significant, as can impacts of individual large-volume releases (either accidental or intentional).

Blackwater is sewage, wastewater from toilets and medical facilities, which can contain harmful bacteria, pathogens, diseases, viruses, intestinal parasites, and harmful nutrients. Discharges of untreated or inadequately treated sewage can cause bacterial and viral contamination of fisheries and shellfish beds, producing risks to public health. Nutrients in sewage, such as nitrogen and phosphorous, promote excessive algal growth, which consumes oxygen in the water and can lead to fish kills and destruction of other aquatic life. Cruise ships generate, on average, 8.4 gallons/day/person of sewage, and a large cruise ship (3,000 passengers and crew) can generate an estimated 15,000 to 30,000 gallons per day of sewage. 10

Graywater is wastewater from the sinks, showers, galleys, laundry, and cleaning activities aboard a ship. It can contain a variety of pollutant substances, including fecal coliform bacteria, detergents, oil and grease, metals, organics, petroleum hydrocarbons, nutrients, food waste, and medical and dental waste. Sampling done by EPA and the state of Alaska found that untreated graywater from cruise ships can contain pollutants at variable strengths, and that it can contain levels of fecal coliform bacteria one to three times greater than is typically found in untreated domestic wastewater. Cruise ships generate, on average, 67 gallons/day/person of graywater (or, approximately 200,000 gallons per day for a 3,000-person cruise ship); by comparison, residential graywater generation is estimated to be 51 gallons/person/day. 11 Graywater has potential to cause adverse environmental effects because of concentrations of nutrients and other oxygen-demanding materials, in particular. Graywater is typically the largest source of liquid waste generated by cruise ships (90%-95% of the total).

Solid waste generated on a ship includes glass, paper, cardboard, aluminum and steel cans, and plastics. It can be either non-hazardous or hazardous in nature. Solid waste that enters the ocean may become marine debris, and it can then pose a threat to marine organisms, humans, coastal communities, and industries that utilize marine waters. Cruise ships typically manage solid waste by a combination of source reduction, waste minimization, and recycling. However, as much as 75% of solid waste is incinerated on board, and the ash typically is discharged at sea, although some is landed ashore for disposal or recycling. Marine mammals, fish, sea turtles, and birds can be injured or killed from entanglement with plastics and other solid waste that may be released or disposed off of cruise ships. On average, each cruise ship passenger generates at least two pounds of non-hazardous solid waste per day and disposes of two bottles and two cans. 12 With large cruise ships carrying several thousand passengers, the amount of waste generated in a day can be massive. For a large cruise ship, about 8 tons of solid waste are generated during a one-week cruise. 13 It has been estimated that 24% of the solid waste generated by vessels worldwide (by weight) comes from cruise ships. 14 Most cruise ship garbage is treated on board (incinerated, pulped, or ground up) for discharge overboard. When garbage must be off-loaded (for example, because glass and aluminum cannot be incinerated), cruise ships can put a strain on port reception facilities, which are rarely adequate to the task of serving a large passenger vessel (especially at non-North American ports). 15

Cruise ships produce hazardous wastes from a number of on-board activities and processes, including photo processing, dry-cleaning, and equipment cleaning. Types of waste include discarded and expired chemicals, medical waste, batteries, fluorescent lights, and spent paints and thinners, among others. These materials contain a wide range of substances such as hydrocarbons, chlorinated hydrocarbons, heavy metals, paint waste, solvents, fluorescent and mercury vapor light bulbs, various types of batteries, and unused or outdated pharmaceuticals. Although the quantities of hazardous waste generated on cruise ships are relatively small, their toxicity to sensitive marine organisms can be significant. Without careful management, these wastes can find their way into graywater, bilge water, or the solid waste stream.

On a ship, oil often leaks from engine and machinery spaces or from engine maintenance activities and mixes with water in the bilge, the lowest part of the hull of the ship. Oil, gasoline, and byproducts from the biological breakdown of petroleum products can harm fish and wildlife and pose threats to human health if ingested. Oil in even minute concentrations can kill fish or have various sub-lethal chronic effects. Bilge water also may contain solid wastes and pollutants containing high amounts of oxygen-demanding material, oil, and other chemicals, as well as soaps, detergents, and degreasers used to clean the engine room. These chemicals can be highly toxic, causing mortality to marine organisms if the chemicals are discharged. Amounts vary, depending on the size of the ship, but large vessels often have additional waste streams that contain sludge or waste oil and oily water mixtures that can inadvertently get into the bilge. A typical large cruise ship will generate an average of eight metric tons of oily bilge water for each 24 hours of operation. 16 To maintain ship stability and eliminate potentially hazardous conditions from oil vapors in these areas, the bilge spaces need to be flushed and periodically pumped dry. However, before a bilge can be cleared out and the water discharged, the oil that has been accumulated needs to be extracted from the bilge water, after which the extracted oil can be reused, incinerated, and/or off-loaded in port. If a separator, which is normally used to extract the oil, is faulty or is deliberately bypassed, untreated oily bilge water could be discharged directly into the ocean, where it can damage marine life. According to EPA, bilge water is the most common source of oil pollution from cruise ships. 17 A number of cruise lines have been charged with environmental violations related to this issue in recent years.

Cruise ships, large tankers, and bulk cargo carriers use a tremendous amount of ballast water to stabilize the vessel during transport. Ballast water is often taken on in the coastal waters in one region after ships discharge wastewater or unload cargo, and discharged at the next port of call, wherever more cargo is loaded, which reduces the need for compensating ballast. Thus, it is essential to the proper functioning of ships (especially cargo ships), because the water that is taken in compensates for changes in the ship's weight as cargo is loaded or unloaded, and as fuel and supplies are consumed. However, ballast water discharge typically contains a variety of biological materials, including plants, animals, viruses, and bacteria. These materials often include non-native, nuisance, exotic species that can cause extensive ecological and economic damage to aquatic ecosystems. Ballast water discharges are believed to be the leading source of invasive species in U.S. marine waters, thus posing public health and environmental risks, as well as significant economic cost to industries such as water and power utilities, commercial and recreational fisheries, agriculture, and tourism. 18 Studies suggest that the economic cost just from introduction of pest mollusks (zebra mussels, the Asian clam, and shipworms) to U.S. aquatic ecosystems is about $2.2 billion per year. 19 These problems are not limited to cruise ships, and there is little cruise-industry specific data on the issue. Further study is needed to determine the role of cruise ships in the overall problem of introduction of non-native species by vessels.

Air pollution from cruise ships is generated by diesel engines that burn high sulfur content fuel, producing sulfur dioxide, nitrogen oxide, and particulate matter, in addition to carbon monoxide, carbon dioxide, and hydrocarbons. Diesel exhaust has been classified by EPA as a likely human carcinogen. EPA recognizes that emissions from marine diesel engines contribute to unhealthy air and failure to meet air quality standards, as well as visibility degradation, haze, acid deposition, and eutrophication and nitrification of water. 20 EPA estimates that ocean-going vessels account for about 10% of mobile source nitrogen oxide emissions, 24% of mobile source particulate emissions, and 80% of mobile source sulfur dioxide emissions in the United States in 2009. These percentages are expected to increase as other sources of these pollutants are controlled. Emissions from marine diesel engines can be higher on a port-specific basis. Ships are also an important source of greenhouse gas (GHG) pollutants. The International Maritime Organization estimates that international shipping contributed 2.7% of global carbon dioxide emissions in 2007. 21 Vessels also emit significant amounts of black carbon and nitrogen oxides, which contribute to climate change.

One source of environmental pressures on maritime vessels recently has come from states and localities, as they assess the contribution of commercial marine vessels to regional air quality problems when ships are docked in port. A significant portion of vessel emissions occur at sea, but they can impact areas far inland and regions without large commercial ports, according to EPA. Again, there is little cruise-industry specific data on this issue. They comprise only a small fraction of the world shipping fleet, but cruise ship emissions may exert significant impacts on a local scale in specific coastal areas that are visited repeatedly. Shipboard incinerators also burn large volumes of garbage, plastics, and other waste, producing ash that must be disposed of. Incinerators may release toxic emissions as well.

The several waste streams generated by cruise ships are governed by a number of international protocols and U.S. domestic laws, regulations and standards, which are described in this section, but there is no single law or regulation. Moreover, there are overlaps in some areas of coverage, gaps in other areas, and differences in geographic jurisdiction, based on applicable terms and definitions.

The International Maritime Organization (IMO), a body of the United Nations, sets international maritime vessel safety and marine pollution standards. It consists of representatives from 152 major maritime nations, including the United States. The IMO implements the 1973 International Convention for the Prevention of Pollution from Ships, as modified by the Protocol of 1978, known as MARPOL 73/78. Cruise ships flagged under countries that are signatories to MARPOL are subject to its requirements, regardless of where they sail, and member nations are responsible for vessels registered under their respective nationalities. 22 Six Annexes of the Convention cover the various sources of pollution from ships and provide an overarching framework for international objectives, but they are not sufficient alone to protect the marine environment from waste discharges, without ratification and implementation by sovereign states.

• Annex I deals with regulations for the prevention of pollution by oil.
• Annex II details the discharge criteria and measures for the control of pollution by noxious liquid substances carried in bulk.
• Annex III contains general requirements for issuing standards on packing, marking, labeling, and notifications for preventing pollution by harmful substances.
• Annex IV contains requirements to control pollution of the sea by sewage.
• Annex V deals with different types of garbage, including plastics, and specifies the distances from land and the manner in which they may be disposed of.
• Annex VI sets limits on sulfur oxide, nitrogen oxide, and other emissions from marine vessel operations and prohibits deliberate emissions of ozone-depleting substances.

Compliance with the Annexes is voluntary. In order for IMO standards to be binding, they must first be ratified by a total number of member countries whose combined gross tonnage represents at least 50% of the world's gross tonnage, a process that can be lengthy. Parties/countries that have ratified an Annex may propose amendments; MARPOL specifies procedures and timelines for parties to adopt amendments and for amendments to take effect. All six Annexes have been ratified by the requisite number of nations; the most recent is Annex VI, which took effect in May 2005. The United States has ratified Annexes I, II, III, V, and VI, but has taken no action regarding Annex IV. The country where a ship is registered (flag state) is responsible for certifying the ship's compliance with MARPOL's pollution prevention standards. IMO also has established a large number of other conventions, addressing issues such as ballast water management, and the International Safety Management Code, with guidelines for passenger safety and pollution prevention.

Each signatory nation is responsible for enacting domestic laws to implement the convention and effectively pledges to comply with the convention, annexes, and related laws of other nations. In the United States, the Act to Prevent Pollution from Ships (APPS, 33 U.S.C. §§1905-1915, and regulations at 33 CFR Subchapter O—Pollution) implements the provisions of MARPOL and the annexes to which the United States is a party. The most recent U.S. action concerning MARPOL occurred in April 2006, when the Senate acceded to ratification of Annex VI, which regulates air pollution (Treaty Doc. 108-7, Exec. Rept. 109-13). Following that approval, in July 2008, Congress approved legislation to implement the standards in Annex VI, through regulations to be promulgated by EPA in consultation with the U.S. Coast Guard ( P.L. 110-280 ). Even before enactment of this legislation, the United Stated participated in international negotiations to strengthen MARPOL Annex VI , which resulted in amendments to Annex VI in October 2008 (see discussion of " Air Pollution ," below). 23

APPS applies to all U.S.-flagged ships anywhere in the world and to all foreign-flagged vessels operating in navigable waters of the United States or while at port under U.S. jurisdiction. The Coast Guard has primary responsibility to prescribe and enforce regulations necessary to implement APPS in these waters. The regulatory mechanism established in APPS to implement MARPOL is separate and distinct from the Clean Water Act and other federal environmental laws.

One of the difficulties in implementing MARPOL arises from the very international nature of maritime shipping. The country that the ship visits can conduct its own examination to verify a ship's compliance with international standards and can detain the ship if it finds significant noncompliance. Under the provisions of the Convention, the United States can take direct enforcement action under U.S. laws against foreign-flagged ships when pollution discharge incidents occur within U.S. jurisdiction. When incidents occur outside U.S. jurisdiction or jurisdiction cannot be determined, the United States refers cases to flag states, in accordance with MARPOL. The 2000 GAO report documented that these procedures require substantial coordination between the Coast Guard, the State Department, and other flag states and that, even when referrals have been made, the response rate from flag states has been poor. 24

In the United States, several federal agencies have some jurisdiction over cruise ships in U.S. waters, but no one agency is responsible for or coordinates all of the relevant government functions. The U.S. Coast Guard and EPA have principal regulatory and standard-setting responsibilities, and the Department of Justice prosecutes violations of federal laws. In addition, the Department of State represents the United States at meetings of the IMO and in international treaty negotiations and is responsible for pursuing foreign-flag violations. Other federal agencies have limited roles and responsibilities. For example, the National Oceanic and Atmospheric Administration (NOAA, Department of Commerce) works with the Coast Guard and EPA to report on the effects of marine debris. The Animal and Plant Health Inspection Service (APHIS) is responsible for ensuring quarantine inspection and disposal of food-contaminated garbage (these APHIS responsibilities are part of the Department of Homeland Security). In some cases, states and localities have responsibilities as well. This section describes U.S. laws and regulations that apply to cruise ship discharges.

The Federal Water Pollution Control Act, or Clean Water Act (CWA), is the principal U.S. law concerned with limiting polluting activity in the nation's streams, lakes, estuaries, and coastal waters. The act's primary mechanism for controlling pollutant discharges is the National Pollutant Discharge Elimination System (NPDES) program, authorized in Section 402. In accordance with the NPDES program, pollutant discharges from point sources—a term that includes vessels—are prohibited unless a permit has been obtained. While sewage is defined as a pollutant under the act, sewage discharges from cruise ships and other vessels are statutorily exempt from this definition and are therefore exempt from the requirement to obtain an NPDES permit.

Marine Sanitation Devices

Section 312 of the Clean Water Act seeks to address this gap by prohibiting the dumping of untreated or inadequately treated sewage from vessels into the navigable waters of the United States (defined in the act as within 3 miles of shore). Cruise ships are subject to this prohibition. It is implemented jointly by EPA and the Coast Guard. Under Section 312, commercial and recreational vessels with installed toilets are required to have marine sanitation devices (MSDs), which are designed to prevent the discharge of untreated sewage. EPA is responsible for developing performance standards for MSDs, and the Coast Guard is responsible for MSD design and operation regulations and for certifying MSD compliance with the EPA rules. MSDs are designed either to hold sewage for shore-based disposal or to treat sewage prior to discharge. Beyond 3 miles, raw sewage can be discharged.

The Coast Guard regulations cover three types of MSDs (33 CFR Part 159). Large vessels, including cruise ships, use either Type II or Type III MSDs. In Type II MSDs, the waste is either chemically or biologically treated prior to discharge and must meet limits of no more than 200 fecal coliform per 100 milliliters and no more than 150 milligrams per liter of suspended solids. Type III MSDs store wastes and do not treat them; the waste is pumped out later and treated in an onshore system or discharged outside U.S. waters. Type I MSDs use chemicals to disinfect the raw sewage prior to discharge and must meet a performance standard for fecal coliform bacteria of not greater than 1,000 per 100 milliliters and no visible floating solids. Type I MSDs are generally only found on recreational vessels or others under 65 feet in length. The regulations, which have not been revised since 1976, do not require ship operators to sample, monitor, or report on their effluent discharges.

Critics point out deficiencies with this regulatory structure as it affects cruise ships and other large vessels. First, the MSD regulations only cover discharges of bacterial contaminants and suspended solids, while the NPDES permit program for other point sources typically regulates many more pollutants such as chemicals, pesticides, heavy metals, oil, and grease that may be released by cruise ships as well as land-based sources. Second, sources subject to NPDES permits must comply with sampling, monitoring, recordkeeping, and reporting requirements, which do not exist in the MSD rules.

In addition, the Coast Guard, responsible for inspecting cruise ships and other vessels for compliance with the MSD rules, has been heavily criticized for poor enforcement of Section 312 requirements. In its 2000 report, the GAO said that Coast Guard inspectors "rarely have time during scheduled ship examinations to inspect sewage treatment equipment or filter systems to see if they are working properly and filtering out potentially harmful contaminants." GAO reported that a number of factors limit the ability of Coast Guard inspectors to detect violations of environmental law and rules, including the inspectors' focus on safety, the large size of a cruise ship, limited time and staff for inspections, and the lack of an element of surprise concerning inspections. 25 The Coast Guard carries out a wide range of responsibilities that encompass both homeland security (ports, waterways, and coastal security, defense readiness, drug and migrant interdiction) and non-homeland security (search and rescue, marine environmental protection, fisheries enforcement, aids to navigation). Since the September 11 terrorist attacks on the United States, the Coast Guard has focused more of its resources on homeland security activities. 26 One likely result is that less of the Coast Guard's time and resources are available for vessel inspections for MSD or other environmental compliance.

Annex IV of MARPOL was drafted to regulate sewage discharges from vessels. It generally requires that ships be equipped with either a sewage treatment plant, sewage comminuting (i.e., to grind or macerate solids) and disinfecting system, or a sewage holding tank. It has entered into force internationally and would apply to cruise ships that are flagged in ratifying countries, but because the United States has not ratified Annex IV, it is not mandatory that ships follow it when in U.S. waters. However, its requirements are minimal, even compared with U.S. rules for MSDs. Annex IV requires that vessels be equipped with a certified sewage treatment system or holding tank, but it prescribes no specific performance standards. Within three miles of shore, Annex IV requires that sewage discharges be treated by a certified MSD prior to discharge. Between three and 12 miles from shore, sewage discharges must be treated by no less than maceration or chlorination; sewage discharges beyond 12 miles from shore are unrestricted. Vessels are permitted to meet alternative, less stringent requirements when they are in the jurisdiction of countries where less stringent requirements apply. In U.S. waters, cruise ships and other vessels must comply with the regulations implementing Section 312 of the Clean Water Act.

On some cruise ships, especially many of those that travel in Alaskan waters, sewage is treated using Advanced Wastewater Treatment (AWT) systems that generally provide improved screening, treatment, disinfection, and sludge processing as compared with traditional Type II MSDs. AWTs are believed to be very effective in removing pathogens, oxygen demanding substances, suspended solids, oil and grease, and particulate metals from sewage, but only moderately effective in removing dissolved metals and nutrients (nitrogen and phosphorous). 27

No Discharge Zones

Section 312 has another means of addressing sewage discharges, through establishment of no-discharge zones (NDZs) for vessel sewage. A state may completely prohibit the discharge of both treated and untreated sewage from all vessels with installed toilets into some or all waters over which it has jurisdiction (up to 3 miles from land). To create a no-discharge zone to protect waters from sewage discharges by cruise ships and other vessels, the state must apply to EPA under one of three categories.

• NDZ based on the need for greater environmental protection, and the state demonstrates that adequate pumpout facilities for safe and sanitary removal and treatment of sewage from all vessels are reasonably available. As of 2009, this category of designation has been used for waters representing part or all of the waters of 26 states, including a number of inland states.
• NDZ for special waters found to have a particular environmental importance (e.g., to protect environmentally sensitive areas such as shellfish beds or coral reefs); it is not necessary for the state to show pumpout availability. This category of designation has been used twice (state waters within the Florida Keys National Marine Sanctuary and the Boundary Waters Canoe area of Minnesota).
• NDZ to prohibit the discharge of sewage into waters that are drinking water intake zones; it is not necessary for the state to show pumpout availability. This category of designation has been used to protect part of the Hudson River in New York.

In the 2008 Discharge Assessment Report, EPA identified several possible options to address sewage from cruise ships, such as revising standards for the discharge of treated sewage effluent, restricting discharge of treated or untreated sewage effluent (e.g., no discharge out to 3 miles from shore), requiring sampling and testing of wastewater treatment equipment to ensure that its meets applicable standards, requiring certain reports by cruise ship operators, or imposing uniform requirements on all ships as a condition of port entry and within U.S. waters. 28

Under current federal law, graywater is not defined as a pollutant, nor is it generally considered to be sewage. There are no separate federal effluent standards for graywater discharges. The Clean Water Act only includes graywater in its definition of sewage for the express purpose of regulating commercial vessels in the Great Lakes, under the Section 312 MSD requirements. However, those rules prescribe limits only for bacterial contaminant content and total suspended solids in graywater. Pursuant to a state law in Alaska, graywater must be treated prior to discharge into that state's waters (see " Alaskan Activities ," below). In addition, in 2008, EPA issued a CWA general permit applicable to large commercial vessels, including cruise ships, that contains restrictions on graywater discharges similar to those that apply in Alaskan waters (see " EPA's Response: General Permits for Vessels ," below).

The National Marine Sanctuaries Act (16 USC § 1431 et seq.) authorizes NOAA to designate National Marine Sanctuaries where certain discharges, including graywater, may be restricted to protect sensitive ecosystems or fragile habitat, such as coral. NOAA regulations do restrict such discharges from cruise ships and other vessels in areas such as the Monterey Bay National Marine Sanctuary and the Florida Keys National Marine Sanctuary.

In the 2008 Discharge Assessment Report, EPA identified several options or alternatives for addressing graywater discharges, such as establishing and/or revising standards for graywater discharges, placing geographic restrictions on graywater discharges, requiring monitoring and reporting, or imposing penalties for failure to meet graywater standards. 29

Cruise ship discharges of solid waste are governed by two laws. Title I of the Marine Protection, Research and Sanctuaries Act (MPRSA, 33 U.S.C. §§ 1402-1421) applies to cruise ships and other vessels and makes it illegal to transport garbage from the United States for the purpose of dumping it into ocean waters without a permit or to dump any material transported from a location outside the United States into U.S. territorial seas or the contiguous zone (within 12 nautical miles from shore) or ocean waters. EPA is responsible for issuing permits that regulate the disposal of materials at sea (except for dredged material disposal, for which the U.S. Army Corps of Engineers is responsible). Beyond waters that are under U.S. jurisdiction, no MPRSA permit is required for a cruise ship to discharge solid waste. The routine discharge of effluent incidental to the propulsion of vessels is explicitly exempted from the definition of dumping in the MPRSA. 30

The Act to Prevent Pollution from Ships (APPS, 33 U.S.C. §§ 1901-1915) and its regulations, which implement U.S.-ratified provisions of MARPOL Annex V, also apply to cruise ships. APPS prohibits the discharge of all garbage within 3 nautical miles of shore, certain types of garbage within 12 nautical miles offshore, and plastic anywhere. As described above, it applies to all vessels, whether seagoing or not, regardless of flag, operating in U.S. navigable waters and the Exclusive Economic Zone (EEZ). It is administered by the Coast Guard which carries out inspection programs to insure the adequacy of port facilities to receive offloaded solid waste. According to EPA, there have been discharges of solid waste and plastic from cruise ships. 31 The IMO also is reportedly evaluating the need to amend Annex V of MARPOL.

In the 2008 Discharge Assessment Report, EPA identified several possible options to address solid waste from cruise ships, such as increasing the use and range of on-board garbage handling and treatment technologies (e.g., compactors and incinerators); initiating a rulemaking to provide stronger waste management plans than the current voluntary cruise industry practices; prohibiting discharge of incinerator ash from cruise ships into U.S. waters; expanding port reception facilities to accept solid waste; or ensuring that there is no discharge of solid waste into the marine environment through monitoring and sanctions. 32

The Resource Conservation and Recovery Act (RCRA, 42 U.S.C. §§ 6901-6991k) is the primary federal law that governs hazardous waste management through a "cradle-to-grave" program that controls hazardous waste from the point of generation until ultimate disposal. The act imposes management requirements on generators, transporters, and persons who treat or dispose of hazardous waste. Under this act, a waste is hazardous if it is ignitable, corrosive, reactive, or toxic, or appears on a list of about 100 industrial process waste streams and more than 500 discarded commercial products and chemicals. Treatment, storage, and disposal facilities are required to have permits and comply with operating standards and other EPA regulations.

The owner or operator of a cruise ship may be a generator and/or a transporter of hazardous waste, and thus subject to RCRA rules. Issues that the cruise ship industry may face relating to RCRA include ensuring that hazardous waste is identified at the point at which it is considered generated; ensuring that parties are properly identified as generators, storers, treaters, or disposers; and determining the applicability of RCRA requirements to each. Hazardous wastes generated onboard cruise ships are stored onboard until the wastes can be offloaded for recycling or disposal in accordance with RCRA. 33

A range of activities on board cruise ships generate hazardous wastes and toxic substances that would ordinarily be presumed to be subject to RCRA—for example, for use of chemicals in cleaning and painting, or in passenger services such as beauty parlors and photo labs. Cruise ships are potentially subject to RCRA requirements to the extent that chemicals used for operations such as ship maintenance and passenger services result in the generation of hazardous wastes. However, it is not entirely clear what regulations apply to the management and disposal of these wastes. 34 RCRA rules that cover small-quantity generators (those that generate more than 100 kilograms but less than 1,000 kilograms of hazardous waste per month) are less stringent than those for large-quantity generators (generating more than 1,000 kilograms per month), and it is unclear whether cruise ships are classified as large or small generators of hazardous waste. Moreover, some cruise companies argue that they generate less than 100 kilograms per month and therefore should be classified in a third category, as "conditionally exempt small-quantity generators," a categorization that allows for less rigorous requirements for notification, recordkeeping, and the like. 35

A release of hazardous substances by a cruise ship or other vessel could also theoretically trigger the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, or Superfund, 42 U.S.C. §§ 9601-9675), but it does not appear to have been used in response to cruise ship releases. CERCLA requires that any person in charge of a vessel shall immediately notify the National Response Center of any release of a hazardous substance in amounts above regulatory thresholds (other than discharges in compliance with a federal permit under the Clean Water Act or other environmental law, as these discharges are exempted) into waters of the United States or the contiguous zone. Notification is required for releases in amounts determined by EPA that may present substantial danger to the public health, welfare, or the environment. EPA has identified 500 wastes as hazardous substances under these provisions and issued rules on quantities that are reportable, covering releases as small as 1 pound of some substances (40 CFR Part 302). CERCLA authorizes the President (acting through the Coast Guard in coastal waters) to remove and provide for remedial action relating to the release.

In addition to RCRA, hazardous waste discharges from cruise ships are subject to Section 311 of the Clean Water Act, which prohibits the discharge of hazardous substances in harmful quantities into or upon the navigable waters of the United States, adjoining shorelines, or into or upon the waters of the contiguous zone.

In the 2008 Discharge Assessment Report, EPA identified several possible options for addressing hazardous wastes, such as establishing standards of BMPs to decrease contaminants in hazardous wastes or the volume of hazardous waste on cruise ships; beginning a rulemaking to prohibit the discharge of hazardous materials into U.S. waters out to the 200-mile Exclusive Economic Zone; increasing inspections on cruise ships; or increasing inspections of authorized facilities that receive cruise ship hazardous wastes. 36

Section 311 of the Clean Water Act, as amended by the Oil Pollution Act of 1990 (33 U.S.C. §§ 2701-2720), applies to cruise ships and prohibits discharge of oil or hazardous substances in harmful quantities into or upon U.S. navigable waters, or into or upon the waters of the contiguous zone, or which may affect natural resources in the U.S. EEZ (extending 200 miles offshore). Coast Guard regulations (33 CFR §151.10) prohibit discharge of oil within 12 miles from shore, unless passed through a 15-ppm oil water separator, and unless the discharge does not cause a visible sheen. Beyond 12 miles, oil or oily mixtures can be discharged while a vessel is proceeding en route and if the oil content without dilution is less than 100 ppm. Vessels are required to maintain an Oil Record Book to record disposal of oily residues and discharges overboard or disposal of bilge water.

In addition to Section 311 requirements, the Act to Prevent Pollution from Ships (APPS) implements MARPOL Annex I concerning oil pollution. APPS applies to all U.S. flagged ships anywhere in the world and to all foreign flagged vessels operating in the navigable waters of the United States, or while at a port under U.S. jurisdiction. To implement APPS, the Coast Guard has promulgated regulations prohibiting the discharge of oil or oily mixtures into the sea within 12 nautical miles of the nearest land, except under limited conditions. However, because most cruise lines are foreign registered and because APPS only applies to foreign ships within U.S. navigable waters, the APPS regulations have limited applicability to cruise ship operations. In addition, most cruise lines have adopted policies that restrict discharges of machinery space waste within three miles from shore.

In the 2008 Discharge Assessment Report, EPA identified several possible options for addressing oily bilge water from cruise ships, such as establishing standards; conducting research on alternative lubricants; treating effluents from oily bilge water to meet specified standards and establishing penalties for failure to meet standards; banning discharge of bilge water into U.S. waters; or revising inspection practices to more aggressively identify noncompliant equipment. 37

Since the 1970s, Clean Water Act regulations had exempted ballast water and other discharges incidental to the normal operation of cruise ships and other vessels from NPDES permit requirements. Because of the growing problem of introduction of invasive species into U.S. waters via ballast water (see discussion, page 5 ), in January 1999, a number of conservation organizations, fishing groups, Native American tribes, and water agencies petitioned EPA to repeal its 1973 regulation exempting ballast water discharge, arguing that ballast water should be regulated as the "discharge of a pollutant" under the Clean Water Act's Section 402 permit program. EPA rejected the petition in September 2003, saying that the "normal operation" exclusion is long-standing agency policy, to which Congress has acquiesced twice (in 1979 and 1996) when it considered the issue of aquatic nuisance species in ballast water and did not alter EPA's CWA interpretation. 38 Further, EPA said that other ongoing federal activities related to control of invasive species in ballast water are likely to be more effective than changing the NPDES rules. 39 Until 2004, these efforts to limit ballast water discharges by cruise ships and other vessels were primarily voluntary, except in the Great Lakes. Since then, all vessels equipped with ballast water tanks must have a ballast water management plan. 40

After the denial of their administrative petition, the environmental groups filed a lawsuit seeking to force EPA to rescind the regulation that exempts ballast water discharges from CWA permitting. In 2005, a federal district court ruled in favor of the groups, and in 2006, the court remanded the matter to EPA with an order that the challenged regulation be set aside by September 30, 2008. The ruling was upheld on appeal in July 2008. 41

EPA's Response: General Permits for Vessels

Significantly, while the focus of the environmental groups' challenge was principally to EPA's permitting exemption for ballast water discharges, the court's ruling—and its mandate to EPA to rescind the exemption in 40 CFR § 122.3(a)—applies fully to other types of vessel discharges that were covered by the long-standing regulatory exemption for "discharges incidental to the normal operation of vessels," including graywater and bilge water. In response to the court's order, in December 2008, EPA issued a Clean Water Act general permit, 42 the Vessel General Permit (VGP), applicable to an estimated 69,000 large recreational and commercial vessels, including tankers, freighters, barges, and approximately 175 U.S. and foreign flagged cruise ships that carry and provide overnight accommodations for more than 100 passengers. 43

The VGP applies to pollutant discharges incidental to the normal operation from non-recreational vessels that are 79 feet or more in length, and to ballast water discharges from commercial vessels of less than 79 feet and commercial fishing vessels of any length. Geographically, it applies to discharges into waters of the United States in all states and territories, extending to the reach of the 3-mile territorial limit.

In the permit, EPA identified 26 types of waste streams from the normal operation of covered vessels (some are not applicable to all vessel types). The types of pollutant discharges subject to the permit include aquatic nuisance species, nutrients, pathogens, oil and grease, metals, and pollutants with toxic effects. Most of the categories of waste streams from the normal operations of these vessels would be controlled by best management practices (BMPs) that are described in the permit, many of which are already practiced or are required by existing regulations. To control ballast water discharges, the VGP primarily relies on existing Coast Guard requirements (at 33 CFR Part 151, Subparts C and D), plus certain flushing and ballast exchange practices, especially for vessels in Pacific nearshore areas. To control discharges of bilge water, the draft VGP provides for BMPs, which EPA indicates are consistent with current rules and industry practice. Monitoring, recordkeeping, and reporting requirements apply.

The VGP does not include sewage discharges from vessels, which are already regulated under CWA Section 312, as discussed previously in this report. Likewise, discharges of wastes associated with passenger services on cruise ships, such as photo developing and dry cleaning, that are toxic to the environment are not authorized by the permit.

Under the VGP, cruise ships are subject to more detailed requirements for certain discharges, such as graywater and pool and spa water, and additional monitoring and reporting. It includes BMPs as well as numeric effluent limits for fecal coliform and residual chlorine in cruise ship discharges of graywater that are based on U.S. Coast Guard rules for discharge of treated sewage or graywater in Alaska (see discussion below, page 19 ). It also includes operational limits on cruise ship graywater discharges in nutrient-impaired waters, such as Chesapeake Bay or Puget Sound.

The 110 th Congress considered ballast water discharge issues, specifically legislation to provide a uniform national approach for addressing aquatic nuisance species from ballast water under a program administered by the Coast Guard ( S. 1578 , ordered reported by the Senate Commerce Committee on September 27, 2007; and H.R. 2830 , passed by the House April 28, 2008). Some groups opposed S. 1578 and H.R. 2830 , because the legislation would preempt states from enacting ballast water management programs more stringent than Coast Guard requirements, while the CWA does allow states to adopt requirements more stringent than in federal rules. Also, while the CWA permits citizen suits to enforce the law, the legislation included no citizen suit provisions. There was no further action on this legislation.

The Clean Air Act (42 U.S.C. 7401 et seq.) is the principal federal law that addresses air quality concerns. It requires EPA to set health-based standards for ambient air quality, sets standards for the achievement of those standards, and sets national emission standards for large and ubiquitous sources of air pollution, including mobile sources. Cruise ships emissions were not regulated until February 2003. At that time, EPA promulgated emission standards for new marine diesel engines on large vessels (called Category 3 marine engines) such as container ships, tankers, bulk carriers, and cruise ships flagged or registered in the United States. 44 The 2003 rule resulted from settlement of litigation brought by the environmental group Bluewater Network after it had petitioned EPA to issue stringent emission standards for large vessels and cruise ships. Standards in the rule are equivalent to internationally negotiated standards set in Annex VI of the MARPOL protocol for nitrogen oxides, which engine manufacturers currently meet, according to EPA. 45 Emissions from these large, primarily ocean-going vessels (including container ships, tankers, bulk carriers, as well as cruise ships) had not previously been subject to EPA regulation. The rule is one of several EPA regulations establishing emissions standards for nonroad engines and vehicles, under Section 213(a) of the Clean Air Act. Smaller marine diesel engines are regulated under rules issued in 1996 and 1999.

In the 2003 rule, EPA announced that it would continue to review issues and technology related to emissions from large marine vessel engines in order to promulgate additional, more stringent emission standards for very large marine engines and vessels later. Addressing long-term standards in a future rulemaking, EPA said, could facilitate international efforts through the IMO (since the majority of ships used in international commerce are flagged in other nations), while also permitting the United States to proceed, if international standards are not adopted in a timely manner. Environmental groups criticized EPA for excluding foreign-flagged vessels that enter U.S. ports from the marine diesel engine rules and challenged the 2003 rules in federal court. The rules were upheld in June 2004. 46 EPA said that it would consider including foreign vessels in the future rulemaking to consider more stringent standards.

As noted previously, the 110 th Congress enacted legislation to implement MARPOL Annex VI, concerning standards to control air pollution from vessels. Soon after that U.S. action, in October 2008, the IMO adopted amendments to Annex VI that to establish stringent new global nitrogen oxide standards beginning in 2011, new global fuel sulfur standards beginning in 2012, plus more stringent emission controls that will apply in designated Emission Control Areas (ECAs). The United States supported the amendments during IMO negotiations. Complementing the IMO revisions, in December 2009, EPA promulgated changes to the 2003 CAA rules for Category 3 marine engines that essentially adopt the amended IMO requirements. 47 The EPA rule also establishes emissions standards for hydrocarbons and carbon monoxide. Like the new Annex VI requirements, the EPA rule applies to newly built engines (not existing) and only to U.S.-flagged or registered vessels. On the latter point, EPA said that engines on foreign vessels are subject to the nitrogen oxide limits in MARPOL Annex VI, which the United States can enforce through the Act to Prevent Pollution from Ships (APPS).

Related to these actions, in October 2010, the IMO approved a U.S. request to designate waters in the U.S. Caribbean (around Puerto Rico and the U.S. Virgin Islands) as an ECA. A treaty amendment to Annex VI will be circulated among IMO members, and if approved by July 2011, ships operating in the designated area would be subject to more stringent emission limitations for sulfur oxides, nitrogen oxides, and particulate matter beginning in 2014.

The various laws and regulations described here apply to different geographic areas, depending on the terminology used. For example, the Clean Water Act treats navigable waters, the contiguous zone, and the ocean as distinct entities. The term "navigable waters" is defined to mean the waters of the United States, including the territorial seas (33 U.S.C. §1362(7)). In turn, the territorial seas are defined in that act as extending a distance of 3 miles seaward from the baseline (33 U.S.C. §1362(8)); the baseline generally means the land or shore. In 1988, President Reagan signed a proclamation (Proc. No. 5928, December 27, 1988, 54 Federal Register 777) providing that the territorial sea of the United States extends to 12 nautical miles from the U.S. baseline. However, that proclamation had no effect on the geographic reach of the Clean Water Act.

The contiguous zone is defined in the CWA to mean the entire zone established by the United States under Article 24 of the Convention of the Territorial Sea and the Contiguous Zone (33 U.S.C. §1362(9)). That convention defines "contiguous zone" as extending from the baseline from which the territorial sea is measured to not beyond 12 miles. In 1999, President Clinton signed a proclamation (Proc. No. 7219 of August 2, 1999, 64 Federal Register 48701) giving U.S. authorities the right to enforce customs, immigration, or sanitary laws at sea within 24 nautical miles from the baseline, doubling the traditional 12-mile width of the contiguous zone. As with the 1988 presidential proclamation, this proclamation did not amend any statutory definitions (as a general matter, a presidential proclamation cannot amend a statute). Thus, for purposes of the Clean Water Act, the territorial sea remains 3 miles wide, and the contiguous zone extends from 3 to 12 miles. Under CERCLA, "navigable waters" means waters of the United States, including the territorial seas (42 U.S.C. §9601(15)), and that law incorporates the Clean Water Act's definitions of "territorial seas" and "contiguous zone" (42 U.S.C. §9601(30)).

The CWA defines the "ocean" as any portion of the high seas beyond the contiguous zone (33 U.S.C. §1362(10)). In contrast, the MPRSA defines "ocean waters" as the open seas lying seaward beyond the baseline from which the territorial sea is measured, as provided for in the Convention of the Territorial Sea and the Contiguous Zone (33 U.S.C. §1402(b)).

Limits of jurisdiction are important because they define the areas where specific laws and rules apply. For example, the Clean Water Act MSD standards apply to sewage discharges from vessels into or upon the navigable waters, and Section 402 NPDES permits are required for point source discharges (excluding vessels) into the navigable waters. Section 311 of the CWA, as amended by the Oil Pollution Act, addresses discharges of oil or hazardous substances into or upon the navigable waters of the United States or the waters of the contiguous zone. Provisions of the Act to Prevent Pollution from Ships (APPS, 33 U.S.C. §§1901-1915) concerning discharges of oil and noxious substances apply to navigable waters. Other provisions of that same act concerning garbage and plastics apply to navigable waters or the EEZ, but the term "navigable waters" is not defined in APPS. The MPRSA regulates ocean dumping within the area extending 12 nautical miles seaward from the baseline and regulates transport of material by U.S.-flagged vessels for dumping into ocean waters.

Further complicating jurisdictional considerations is the fact that the Clean Water Act refers to these distances from shore in terms of miles, without other qualification, which is generally interpreted to mean an international mile or statute mile. APPS, the MPRSA, and the two presidential proclamations refer to distances in terms of nautical miles from the baseline. These two measures are not identical: a nautical mile is a unit of distance used primarily at sea and in aviation; it equals 6,080 feet and is 15% longer than an international or statute mile. 48

In Alaska, where tourism and commercial fisheries are key contributors to the economy, cruise ship pollution has received significant attention. After the state experienced a three-fold increase in the number of cruise ship passengers visits during the 1990s, 49 concern by Alaska Natives and other groups over impacts of cruise ship pollution on marine resources began to increase. In one prominent example of environmental violations, in July 1999, Royal Caribbean Cruise Lines entered a federal criminal plea agreement involving total penalties of $6.5 million for violations in Alaska, including knowingly discharging oil and hazardous substances (including dry-cleaning and photo processing chemicals). The company admitted to a fleet-wide practice of discharging oil-contaminated bilge water. The Alaska penalties were part of a larger $18 million total federal plea agreement involving environmental violations in multiple locations, including Florida, New York, and California.

Public concern about the Royal Caribbean violations led the state to initiate a program in December 1999 to identify cruise ship waste streams. Voluntary sampling of large cruise ships in 2000 indicated that waste treatment systems on most ships did not function well and discharges greatly exceeded applicable U.S. Coast Guard standards for Type II MSDs. Fecal coliform levels sampled during that period averaged 12.8 million colonies per 100 milliliters in blackwater and 1.2 million in graywater, far in excess of the Coast Guard standard of 200 fecal coliforms per 100 milliliters.

Concurrent with growing regional interest in these problems, attention to the Alaska issues led to passage of federal legislation in December 2000 (Certain Alaskan Cruise Ship Operations, Division B, Title XIV of the Miscellaneous Appropriations Bill, H.R. 5666 , in the Consolidated Appropriations Act, 2001 ( P.L. 106-554 ); 33 U.S.C. § 1901 Note). This law established standards for vessels with 500 or more overnight passengers and generally prohibited discharge of untreated sewage and graywater in navigable waters of the United States within the state of Alaska. It authorized EPA to promulgate standards for sewage and graywater discharges from cruise ships in these waters. Until such time as EPA issues regulations, cruise ships may discharge treated sewage wastes in Alaska waters only while traveling at least 6 knots and while at least 1 nautical mile from shore, provided that the discharge contains no more than 200 fecal coliforms per 100 ml and no more than 150 mg/l total suspended solids (the same limits prescribed in federal regulations for Type II MSDs).

The law also allows for discharges of treated sewage and graywater inside of one mile from shore and at speeds less than 6 knots (thus including stationary discharges while a ship is at anchor) for vessels with systems that can treat sewage and graywater to a much stricter standard. Such vessels must meet these minimum effluent standards: no more than 20 fecal coliforms per 100 ml, no more than 30 mg/l of total suspended solids, and total residual chlorine concentrations not to exceed 10 mg/l. The legislation requires sampling, data collection, and recordkeeping by vessel operators to facilitate Coast Guard oversight and enforcement. The Coast Guard issued regulations to implement the federal law in 2001; the rules became effective immediately upon publication. 50 The regulations stipulate minimum sampling and testing procedures and provide for administrative and criminal penalties for violations of the law, as provided in the legislation.

Pursuant to Title IV, EPA has carried out a multi-year project to evaluate the performance of various treatment systems and to determine whether revised and/or additional standards for sewage and graywater discharges from large cruise ships operating in Alaska are warranted. In particular, EPA sampled wastewater from four cruise ships that operated in Alaska during the summers of 2004 and 2005 to characterize graywater and sewage generated onboard and to evaluate the performance of various treatment systems. 51 Much of the information collected through this effort is summarized in the 2008 Cruise Ship Discharge Assessment Report. Also in 2004, EPA distributed a survey questionnaire on the effectiveness, costs, and impacts of sewage and graywater treatment devices for large cruise vessels in Alaska. EPA has collaborated with the state of Alaska on a cruise ship plume tracking survey (in 2001) and a study in Skagway Harbor to estimate the near-field dilution of treated sewage and graywater discharges from docked cruise ships (in 2008). These sampling efforts generally show that advanced wastewater treatment systems are effective in treating pathogens, oxygen-demanding materials, suspended solids, oil and grease, and particulate matter, and are moderately effective in treating metals, volatile chemicals, and nutrients.

Building on the federal legislation enacted in 2000, the state of Alaska enacted its own law in 2001 (AS 46.03.460-AS 46.03.490). The state law sets standards and sampling requirements for the underway discharge of blackwater in Alaska that are identical to the blackwater/sewage standards in the federal law. However, because of the high fecal coliform counts detected in graywater in 2000, the state law also extends the effluent standards to discharges of graywater. Sampling requirements for all ships took effect in 2001, as did effluent standards for blackwater discharges by large cruise ships (defined as providing overnight accommodations to 250 or more). Effluent standards for graywater discharges by large vessels took effect in 2003. Small ships (defined as providing overnight accommodations for 50 to 249 passengers) were allowed three years to come into compliance with all effluent standards. The law also established a scientific advisory panel to evaluate the effectiveness of the law's implementation and to advise the state on scientific matters related to cruise ship impacts on the Alaskan environment and public health.

According to the state, the federal and state standards have prompted large ships to either install advanced wastewater treatment systems that meet the effluent standards or to manage wastes by holding all of their wastewater for discharge outside of Alaskan waters (beyond 3 miles from shore). 52 As of 2006, 23 of 28 large cruise ships that operated in Alaskan waters had installed advanced wastewater treatment systems, and the quality of wastewater discharged from large ships has improved dramatically, according to the state.

Small ships, however, have not installed new wastewater treatment systems, and the effluent quality has remained relatively constant, with discharge levels for several pollutants regularly exceeding state water quality standards. In particular, test results indicated that concentrations of free chlorine, fecal coliform, copper, and zinc from stationary smaller vessels pose some risk to aquatic life and also to human health in areas where aquatic life is harvested for raw consumption.

In addition to the state's 2001 action, in August 2006 Alaska voters approved a citizen initiative requiring cruise lines to pay the state a $50 head tax for each passenger and a corporate income tax, increasing fines for wastewater violations, and mandating new environmental regulations for cruise ships (such as a state permit for all discharges of treated wastewater). Revenues from the taxes will go to local communities affected by tourism and into public services and facilities used by cruise ships. Supporters of the initiative contend that the cruise industry does not pay enough in taxes to compensate for its environmental harm to the state and for the services it uses. Opponents argued that the initiative would hurt Alaska's competitiveness for tourism, and have filed a legal challenge to the tax in federal court. At least two cruise ship lines (Norwegian Cruise and Royal Caribbean) have reportedly stopped operating cruise ships in Alaskan waters because of the citizen initiative. In 2009, Alaska enacted legislation (HB 134) giving the Department of Environmental Conservation more time to implement the stringent wastewater treatment standards and creating a scientific review board to assess whether the standards can be achieved.

Activity to regulate or prohibit cruise ship discharges also has occurred in several other states.

In April 2004, the state of Maine enacted legislation governing discharges of graywater or mixed blackwater/graywater into coastal waters of the state (Maine LD. 1158). The legislation applies to large cruise ships (with overnight accommodations for 250 or more passengers) and allows such vessels into state waters after January 1, 2006, only if the ships have advanced wastewater treatment systems, comply with discharge and recordkeeping requirements under the federal Alaska cruise ship law, and get a permit from the state Department of Environmental Protection. Under the law, prior to 2006, graywater dischargers were allowed if the ship operated a treatment system conforming to requirements for continuous discharge systems under the Alaska federal and state laws. In addition, the legislation required the state to apply to EPA for designation of up to 50 No Discharge Zones, in order that Maine may gain federal authorization to prohibit blackwater discharges into state waters. EPA approved the state's NDZ request for Casco Bay in June 2006.

California enacted three bills in 2004. One bars cruise ships from discharging treated wastewater while in the state's waters (Calif. A.B. 2672). Another prohibits vessels from releasing graywater (Calif. A.B. 2093), and the third measure prevents cruise ships from operating waste incinerators (Calif. A.B. 471). Additionally, in 2003 California enacted a law that bans passenger ships from discharging sewage sludge and oil bilge water (Calif. A.B. 121), as well as a bill that prohibits vessels from discharging hazardous wastes from photo-processing and dry cleaning operations into state waters (Calif. A.B. 906). Another measure was enacted in 2006: California S.B. 497 requires the state to adopt ballast water performance standards by January 2008 and set specific deadlines for the removal of different types of species from ballast water, mandating that ship operators remove invasive species (including bacteria) by the year 2020.

Several states, including Florida, Washington, and Hawaii, have entered into memoranda of agreement with the industry (through the Cruise Lines International Association and related organizations) providing that cruise ships will adhere to certain practices concerning waste minimization, waste reuse and recycling, and waste management. For example, under a 2001 agreement between industry and the state of Florida, cruise lines must eliminate wastewater discharges in state waters within 4 nautical miles off the coast of Florida, report hazardous waste off-loaded in the United States by each vessel on an annual basis, and submit to environmental inspections by the U.S. Coast Guard.

Similarly, in April 2004 the Washington Department of Ecology, Northwest Cruise Ship Association, and Port of Seattle signed a memorandum of understanding (MOU) that would allow cruise ships to discharge wastewater treated with advanced wastewater treatment systems into state waters and would prohibit the discharge of untreated wastewater and sludge. The MOU has been amended several times and now covers other ports, as well. Environmental advocates are generally critical of such voluntary agreements, because they lack enforcement and penalty provisions. States respond that while the Clean Water Act limits a state's ability to control cruise ship discharges, federal law does not bar states from entering into voluntary agreements that have more rigorous requirements. 53 In June 2009, the Department of Ecology reported that cruise ships visiting the state during the 2008 sailing season mostly complied with the MOU to stop discharging untreated wastewater, and found that wastewater treatment systems generally produce high quality effluent that is as good or better than on-land plants. Although enforcement of what is essentially a voluntary agreement is difficult, the state argues that having something in place to protect water quality is beneficial and enables the state to obtain data on vessels and waste treatment equipment. 54

Pressure from environmental advocates, coupled with the industry's strong desire to promote a positive image, have led the cruise ship industry to respond with several initiatives. Members of the Cruise Lines International Association (CLIA), which represents 25 of the world's largest cruise lines, have adopted a set of waste management practices and procedures for their worldwide operations building on regulations of the IMO and U.S. EPA. The guidelines generally require graywater and blackwater to be discharged only while a ship is underway and at least 4 miles from shore and require that hazardous wastes be recycled or disposed of in accordance with applicable laws and regulations. 55

CLIA's cruise line companies also have implemented Safety Management System (SMS) plans for developing enhanced wastewater systems and increased auditing oversight. These SMS plans are certified in accordance with the IMO's International Safety Management Code. The industry also is working with equipment manufacturers and regulators to develop and test technologies in areas such as lower emission turbine engines and ballast water management for elimination of non-native species. Environmental groups commend industry for voluntarily adopting improved management practices but also believe that enforceable standards are preferable to voluntary standards, no matter how well intentioned. 56

The industry joined with the environmental group Conservation International (CI) to form the Ocean Conservation and Tourism Alliance to work on a number of issues. In December 2003 they announced conservation efforts in four areas to protect biodiversity in coastal areas: improving technology for wastewater management aboard cruise ships, working with local governments to protect the natural and cultural assets of cruise destinations, raising passenger and crew awareness and support of critical conservation issues, and educating vendors to lessen the environmental impacts of products from cruise ship suppliers. Because two-thirds of the top cruise destinations in the world are located in the Caribbean and Mediterranean, two important biodiversity regions, in 2006, CLIA and CI announced a joint initiative to develop a map integrating sensitive marine areas into cruise line navigational charts, with the goal of protecting critical marine and coastal ecosystems.

In 2004, Royal Caribbean Cruises Ltd.(RCCL) announced plans to retrofit all vessels in its 29-ship fleet with advanced wastewater treatment technology, becoming the first cruise line to commit to doing so completely. The company had been the focus of efforts by the environmental group Oceana to pledge to adopt measures that will protect the ocean environment and that could serve as a model for others in the cruise ship industry, in part because of the company's efforts to alter its practices following federal enforcement actions in the 1990s for environmental violations that resulted in RCCL paying criminal fines that totaled $27 million.

Concerns about cruise ship pollution raise issues for Congress in three broad areas: adequacy of laws and regulations, research needs, and oversight and enforcement of existing programs and requirements. Attention to these issues is relatively recent, and more assessment is needed of existing conditions and whether current steps (public and private) are adequate. Bringing the issues to national priority sufficient to obtain resources that will address the problems is a challenge.

A key issue is whether the several existing U.S. laws, international protocols and standards, state activities, and industry initiatives described in this report adequately address management of cruise ship pollution, or whether legislative changes are needed to fill in gaps, remedy exclusions, or strengthen current requirements. As EPA noted in its 2000 white paper, certain cruise ship waste streams such as oil and solid waste are regulated under a comprehensive set of laws and regulations, but others, such as graywater, are excluded or treated in ways that appear to leave gaps in coverage. 57 Graywater is one particular area of interest, since investigations, such as sampling by state of Alaska officials, have found substantial contamination of cruise ship graywater from fecal coliform, bacteria, heavy metals, and dissolved plastics. State officials were surprised that graywater from ships' galley and sink waste streams tested higher for fecal coliform than did the ships' sewage lines. 58 One view advocating strengthened requirements came from the U.S. Commission on Ocean Policy. In its 2004 final report, the Commission advocated clear, uniform requirements for controlling the discharge of wastewater from large passenger vessels, as well as consistent interpretation and enforcement of those requirements. It recommended that Congress establish a new statutory regime that should include

• uniform discharge standards and waste management procedures;
• thorough recordkeeping requirements to track the waste management process;
• required sampling, testing, and monitoring by vessel operators using uniform protocols; and
• flexibility and incentives to encourage industry investment in innovative treatment technologies. 59

A proposal reflecting some of these concepts, the Clean Cruise Ship Act, was introduced in the 111 th Congress as S. 1820 (Durbin) and H.R. 3888 (Farr). No legislative action occurred on either bill. The legislation would amend the Clean Water Act to prohibit cruise vessels entering a U.S. port from discharging sewage, graywater, or bilge water into waters of the United States, including the Great Lakes, except in compliance with prescribed effluent limits and management standards. It further would direct EPA and the Coast Guard to promulgate effluent limits for sewage, graywater, and bilge water discharges from cruise vessels that are no less stringent than the more restrictive standards under the existing federal Alaska cruise ship law described above. It would require cruise ships to treat wastewater wherever they operate and would authorize broadened federal enforcement authority, including inspection, sampling, and testing. The legislation also would impose passenger fees for use by EPA and the Coast Guard to implement the legislation. Environmental advocates supported similar versions of this legislation in previous Congresses. Industry groups have argued that it would target an industry that represents only a small percentage of the world's ships and that environmental standards of the industry, including voluntary practices, already meet or exceed current international and U.S. regulations. 60

As noted above, a few states have passed legislation to regulate cruise ship discharges. If this state-level activity were to increase, Congress could see a need to develop federal legislation that would harmonize differences in the states' approaches.

Another issue for Congress is the status of EPA's efforts to manage or regulate cruise ship wastes. As discussed previously, in 2000 Congress authorized EPA to issue standards for sewage and graywater discharges from large cruise ships operating in Alaska. In response, the agency has been collecting information and assessing the need for additional standards, beyond those provided in P.L. 106-554 , but has not yet proposed any rules. In December 2008, EPA released a Cruise Ship Discharge Assessment Report that builds on a 2007 draft assessment report and the 2000 White Paper. The final report examines five cruise ship waste streams (sewage, graywater, oily bilge water, solid waste, and hazardous waste) and discusses how the waste streams are managed and current actions by the federal government to address the waste streams. For each waste stream, the report identifies possible options and alternatives to address cruise ship discharges, but it also states that EPA has not determined that any of the options are necessary, feasible, or warranted, or that EPA or any other entity has the legal authority to implement the options. 61

Other related issues of interest could include harmonizing the differences presented in U.S. laws for key jurisdictional terms as they apply to cruise ships and other types of vessels; providing a single definition of "cruise ship," which is defined variously in federal and state laws and rules, with respect to gross tonnage of ships, number of passengers carried, presence of overnight passenger accommodations, or primary purpose of the vessel; or requiring updating of existing regulations to reflect improved technology (such as the MSD rules that were issued in 1976).

Several areas of research might help improve understanding of the quantities of waste generated by cruise ships, impacts of discharges and emissions, and the potential for new control technologies.

The U.S. Commission on Ocean Policy noted in its 2004 final report that research can help identify the degree of harm represented by vessel pollution and can assist in prioritizing limited resources to address the most significant threats. The commission identified several directions for research by the Coast Guard, EPA, NOAA, and other appropriate entities on the fates and impacts of vessel pollution: 62

• Processes that govern the transport of pollutants in the marine environment.
• Small passenger vessel practices, including the impacts of stationary discharges.
• Disposal options for concentrated sludge resulting from advanced sewage treatment on large passenger vessels.
• Cumulative impacts of commercial and recreational vessel pollution on particularly sensitive ecosystems, such as coastal areas with low tidal exchange and coral reef systems.
• Impacts of vessel air emissions, particularly in ports and inland waterways where the surrounding area is already having difficulty meeting air quality standards.

In the 2008 Cruise Ship Assessment Report, EPA identified several possible research options, including establishing a detailed nationwide sampling, testing, and monitoring program to gather data; increasing studies on human health an environmental effects of cruise ship discharges; directing research to geographic areas that may be impacted by cruise ship discharges; or directing future assessments to potential cumulative impacts from multiple cruise ships, from stationary cruise ships, and in semi-enclosed environments such as bays and harbors. 63

The 2000 GAO report documented—and EPA's 2000 cruise ship white paper acknowledged—that existing laws and regulations may not be adequately enforced or implemented. GAO said there is need for monitoring of the discharges from cruise ships in order to evaluate the effectiveness of current standards and management. GAO also said that increased federal oversight of cruise ships by the Coast Guard and other agencies is needed concerning maintenance and operation of pollution prevention equipment, falsifying of oil record books (which are required for compliance with MARPOL), and analysis of records to verify proper off-loading of garbage and oily sludge to onshore disposal facilities. 64

The Coast Guard has primary enforcement responsibility for many of the federal programs concerning cruise ship pollution. A key oversight and enforcement issue is the adequacy of the Coast Guard's resources to support its multiple homeland and non-homeland security missions. The resource question as it relates to vessel inspections was raised even before the September 11 terrorist attacks, in the GAO's 2000 report. The same question has been raised since then, in light of the Coast Guard's expanded responsibilities for homeland security and resulting shift in operations, again by the GAO and others. 65

EPA has identified several possible options for enforcement and compliance, including improving monitoring and inspections; rewarding passengers who aid in detecting illegal activities; allowing state personnel (as well as the Coast Guard) to inspect cruise ship pollution control equipment; or charging a passenger fee to put a marine engineer onboard cruise ships to observe ship waste treatment practices. 66

In its 2000 report, GAO also found that the process for referring cruise ship violations to other countries does not appear to be working, either within the Coast Guard or internationally, and GAO recommended that the Coast Guard work with the IMO to encourage member countries to respond when pollution cases are referred to them and that the Coast Guard make greater efforts to periodically follow up on alleged pollution cases occurring outside U.S. jurisdiction.

What happens to all that uneaten food on cruises? These lines are working to reduce waste.

"Green Travel” is a six-part series focusing on what it means to be sustainable travelers, how the industry is moving the needle on greener efforts, and how consumers can reduce their carbon footprint when exploring. If you'd like to contribute to our future reporting and share your experience as a source, you can  click here to fill out this quick form .

While I watched a crew member aboard Holland America Line’s Rotterdam ship haul away my half-eaten order of french fries, I felt a pang of yearning.

I spent nearly two weeks sailing with the line in October and made a point to sample nearly every restaurant on board, including the burger joint Dive-In, but never requested a to-go box at the end of a meal as I might on land. With only a minibar in my stateroom and food always at my beck-and-call, it seemed impractical.

Little did I know that elsewhere on board, a machine probably would soon be chomping on my leftovers.

Holland America Line has installed biodigesters that can break down organic material as part of efforts to shrink its food waste footprint, and parent company Carnival Corp. now has more than 600 of the devices in its fleet.

For many travelers, food is a key part of the cruise experience, with seemingly unlimited options − think buffets − included in the fare . But for all the cuisine passengers enjoy, there is plenty that doesn’t get eaten, and many lines are working to refine their processes for dealing with that waste.

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What happens to food waste on cruise ships?

Carnival, which operates brands including Holland America, Carnival Cruise Line, Princess Cruises and others, generates 1.3 pounds of food waste per person each day on average but can generate as little as 0.6 pounds per person a day, depending on the line, a spokesperson for the company said in an email.

All of that waste is either processed via biodigesters or dehydrators, or offloaded on shore.

Some of the company’s ships have long had dehydrators, which squeeze the water from food waste and lighten the load that can be taken to landfills, compost sites or waste-to-energy facilities. “And that was good, but not necessarily good enough,” said Bill Burke, the company’s chief maritime officer.

The company began a three-pronged approach to food waste in 2019, he said, from the point when the lines stock food to after guests throw away what they don’t eat.

Carnival analyzed the waste and worked to determine what was left over, what the line could reuse in other recipes and where it could cut back. “That’s a significant carbon issue if we’re buying food that we’re not using,” Burke said.

The company has reduced food waste by more than 30% per person when compared with its 2019 baseline, according to its 2022 sustainability report , and has set new goals of 40% by 2025 and 50% by 2030.

Burke said Carnival, which operates the largest number of U.S. sailings, also has worked to reduce single-use plastics, swapping individual yogurt cups for bulk containers, for instance. The biodigesters, which he called the “holy grail,” have rounded out that work, digesting much of the organic waste that before would have been ground up and discharged, turning what’s left into a liquid.

Other companies and cruise lines are working toward similar aims.

Royal Caribbean International uses proprietary technology to track how much food is being wasted − by weighing pans of lasagna before and after they are served, for instance − and amend production accordingly. The cruise line has expanded those efforts, including using point-of-sale data to forecast how much food it will use based on passenger demographics, the itinerary and other information.

“(If) we have 10% more kids, we know we’re going to need significantly more chicken fingers,” said Linken D’Souza, the line’s vice president of food and beverage.

Leveraging that intel will allow them to be proactive, D’Souza said, and eliminate waste before it happens.

Some initiatives have been particularly creative. Norwegian Cruise Line launched zero-waste drinks at a bar on its Prima ship last year, reusing items like banana peels and croissants in cocktails.

Story continues below.

How do biodigesters work?

Carnival uses biodigesters from several companies, including Recoup Technologies, formerly BioHiTech America. Its product uses microorganisms and other bacteria to rapidly process food waste much like a human digestive system might, according to director of technology operations Bob Joyce.

“The way we tend to describe it is just basically as a metal stomach,” he said. What goes in as salad or steak comes out as a smoothie-like mixture the cruise ship can then discharge. “If you can eat it, it can eat it,” he said.

But while the machines, which cost $25,000 to $50,000 depending on the size, can take in a wide range of produce, proteins and starches, Joyce noted that certain items such as walnut shells and steak bones will not break down inside. Crew members sort out inorganic materials beforehand.

The company discharges the liquid at least 12 miles from shore. Holland America’s Rotterdam has nine of them, along with one dehydrator.

“Biodigesters reduce the amount of methane and carbon dioxide emitted into the atmosphere while also reducing the demand on the ocean for complete food waste decomposition,” Carnival said in its sustainability report. The biodigesters processed about 80 million pounds of food waste in 2022, which would have taken up about 1 million cubic feet of space had it been sent to a landfill and released 30,000 metric tons of greenhouse gas emissions, the spokesperson added.

 But that doesn’t mean the waste is good for marine life.

“They’re putting nutrients into the oceans that can disrupt aquatic ecosystems,” said Gregory Keoleian, director of the Center for Sustainable Systems at the University of Michigan.

The kind of human sustenance cruise ships discharge is not typically part of fish and other aquatic creatures’ diets, and introducing it can disturb complex food webs, according to Keoleian. “They didn’t evolve to eat human food waste,” he said.

“Our success – and quite literally, our livelihood – depends on doing our part to protect the vibrant marine ecosystems, beautiful communities, and scenic spaces we operate in,” the Carnival spokesperson said in an emailed statement. “We’re investing in the industry’s smartest solutions to enable sustainable cruising, such as biodigesters, which offer the best available food waste solution on the market today.”

Carnival also acknowledged in 2019 that its vessels had committed environmental crimes and knowingly allowed plastic to be discharged with food waste in the Bahamas. 

What can passengers do?

Keoleian said preventing food waste generation is as important as how it’s managed, and passengers can play a role in minimizing the environmental repercussions.

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That can mean simply wasting less food when they have a meal on board, and being judicious about what food items they pick. “If you look at the environmental impacts of food, what foods they choose to eat will impact the environment differently,” he said. 

Beef, for example, is more carbon-intensive to produce than other sources of protein like chicken or fish or plant-based proteins, he said.

Burke said that in addition to working toward greater sustainability, there are other positive byproducts, such as appealing to younger travelers who prioritize that in particular. “If we want you to cruise on one of our ships, I think it will matter to you how we take care of the ocean. So, it’s not just doing good, it's doing the right thing for business as well.”

Do you find it easier to increase or reduce the amount of waste you produce on cruises? How so?

Nathan Diller is a consumer travel reporter for USA TODAY based in Nashville. You can reach him at [email protected].

• Marine litter
• Media Centre

Marine litter presents a huge problem in our oceans, with some scientists warning that, by 2050, the quantity of plastics in the oceans will outweigh fish. IMO has been regulating marine plastic litter for the last 50 years - from the dumping of waste at sea to discharges from ships.      

IMO is actively working to ensure its existing rules are implemented and is considering new measures, under its strategy and action plan on marine litter. The GloLitter project is working to support specific countries and to raise awareness to address sea based sources of marine litter, including from fisheries. Read more below. 

IMO Strategy to address marine plastic litter from ships - zero plastic waste discharges to sea from ships by 2025

IMO’s Marine Environment Protection Committee (MEPC) in 2021 adopted its Strategy to address marine plastic litter from ships, which sets out the ambitions to reduce marine plastic litter generated from, and retrieved by, fishing vessels; reduce shipping's contribution to marine plastic litter; and improve the effectiveness of port reception and facilities and treatment in reducing marine plastic litter. 

The Strategy sets a vision to "strengthen the international framework and compliance with the relevant IMO instruments, endeavouring to achieve zero plastic waste discharges to sea from ships by 2025".

Download the IMO Strategy to Address Marine Plastic Litter from Ships.

The Strategy also aims to achieve further outcomes, including: enhanced public awareness, education and seafarer training; improved understanding of the contribution of ships to marine plastic litter; improved understanding of the regulatory framework associated with marine plastic litter from ships; strengthened international cooperation; and targeted technical cooperation and capacity-building.

The adoption of the Strategy follows the adoption, in 2018, of the IMO Action Plan to address marine litter alongside  actions to be completed by 2025, which relate to all ships, including fishing vessels. 

The Strategy and action plan supports IMO’s commitment to meeting the targets set in the UN 2030 Sustainable Development Goal 14 ( SDG 14 ) on the oceans.

The Action Plan notes that marine plastic litter enters the marine environment as a result of a wide range of land- and sea-based activities. Both macroplastics (for example, large plastic items such as plastic bags, water bottles and fishing gear) and microplastics (small plastic particles generally five millimetres or less in size) persist in the marine environment and result in harmful effects on marine life and biodiversity, as well as negative impacts on human health. In addition, marine plastic litter negatively impacts on activities such as tourism, fisheries and shipping. This plastic material has the potential to be brought back into the economy by means of reuse or recycling. Studies demonstrate that despite the existing regulatory framework to prevent marine plastic litter from ships, discharges into the sea continue to occur.

The Action Plan provides IMO with a mechanism to identify specific outcomes, and actions to achieve these outcomes, in a way that is meaningful and measureable. The plan builds on existing policy and regulatory frameworks, and identifies opportunities to enhance these frameworks and introduce new supporting measures to address the issue of marine plastic litter from ships.

Specific identified measures include:

a proposed study on marine plastic litter from ships;

looking into the availability and adequacy of port reception facilities;

consideration of making marking of fishing gear mandatory, in cooperation with the Food and Agriculture Organization (FAO);

promoting reporting the loss of fishing gear;

facilitating the delivery of retrieved fishing gear to shore facilities;

reviewing provisions related to the training of fishing vessel personnel and familiarization of seafarers to ensure awareness of the impact of marine plastic litter;

consideration of the establishment of a compulsory mechanism to declare loss of containers at sea and identify number of losses;

enhancing public awareness; and

strengthening international cooperation, in particular FAO and UN Environment.

IMO will continue to work with UN partners, including, the Food and Agriculture Organization (FAO), through the Joint FAO/IMO Ad Hoc Working Group on illegal, unregulated and unreported (IUU) Fishing and Related Matters; the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP); the UN Environment-managed Global Partnership on Marine Litter (GPML); the United Nations Open-ended Informal Consultative Process on Oceans and the Law of the Sea (ICP); and the United Nations Environment Assembly (UNEA).

Download the IMO Action plan here.

GloLitter Partnerships Project to tackle plastic litter from shipping and fisheries

IMO and the Food and Agriculture Organization of the United Nations (FAO) launched the GloLitter Partnerships project in December 2019, with initial funding for the project from the Government of Norway.

GloLitter aims to help the maritime industry move to a low-plastics future by assisting developing countries identify opportunities to prevent and reduce marine litter through the re-use and recycling of plastics within the maritime transport and fisheries sectors, and to decrease the use of plastics in these industries.

The project considers the availability and adequacy of port reception facilities; looks at enhancing awareness of the marine plastics issue within the shipping and fisheries sectors, including seafarers and fishers; and encourages fishing gear to be marked so it can be traced back to its owner if discarded.

The GloLitter project develops guidance documents, training material and toolkits to help enforce existing regulations, including IMO's International Convention for the Prevention of Pollution from Ships (MARPOL) Annex V . Since 1988, this has prohibited the discharge of plastics, including discarded fishing gear, into the sea from ships.

The project also promotes compliance with relevant FAO instruments (including the Voluntary Guidelines on the Marking of Fishing Gear) and targets waste management in ports. Additionally, it emphasises implementation and enforcement of IMO's London Convention London Protocol regime on dumping of wastes at sea, which requires waste (such as from dredging) to be assessed before permits to dump are granted.

The GloLitter project includes private sector participation through a global industry alliance and is seeking partners from major maritime and fisheries companies.

What is marine litter?

Plastic materials in all shapes and sizes are omnipresent in our seas and oceans. They break down extremely slowly in the marine environment, taking in excess of 400 years. Marine litter originates from many sources and causes a wide spectrum of environmental, economic, safety, health and cultural impacts. For example, marine litter can cause harm to sealife if ingested or even death if a marine mammal becomes entangled in litter.

Marine litter has been defined by UN Environment as “any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment. Marine litter consists of items that have been made or used by people and deliberately discarded into the sea or rivers or on beaches; brought indirectly to the sea with rivers, sewage, storm water or winds; accidentally lost, including material lost at sea in bad weather (fishing gear, cargo); or deliberately left by people on beaches and shores.”

Marine litter, including plastics and microplastics, is known to result from land-based sources in massive quantities but can also originate from ships. Debris has been observed in coastal areas, in waters far from anthropogenic pollution sources, in surface waters, in the water column of deep water and in ocean sediments, and from the equator to the poles, including trapped in sea ice.

UN Environment estimates that 15% of marine litter floats on the sea's surface, 15% remains in the water column and 70% rests on the seabed.

According to another study, 5.25 million plastic particles, weighing 268,940 tonnes in total, are currently floating in the world's oceans.

Read the 2018 UNEP report, Single-use plastics - A Roadmap for Sutainability . "Plastic pollution is a defining challenge of our times....Single-use throw away plastics are the biggest contributor every year, millions of plastic bags end up in the environment, thus polluting soil, water bodies, rivers oceans."

What problems does marine litter cause?

In addition to the environmental and health problems posed by marine litter, floating garbage and plastics pose a costly as well as dangerous problem for shipping, as they can be a navigational hazard and become entangled in propellers and rudders.

Another problem requiring urgent remedial action is the massive accumulation of plastics, not only in coastal areas but also in the deep sea.

This litter is harmful to marine life: sea creatures can become trapped inside containers or strangled by nets or ropes, and microplastics can also enter the food chain as they are indigestible when swallowed.

Microplastics

Microplastics are tiny pieces of plastic or fibres increasingly found in the oceans. They can result from the fragmentation of larger plastic items, especially when exposed to sunlight.

They may also be purposefully manufactured for particular industrial or domestic applications. One example is in facial cleansers and body scrubs. It has been estimated that a single shower can result in 100,000 plastic particles entering the ocean.

Microplastics have been found distributed throughout the world’s oceans, on shorelines, in surface waters and seabed sediments, from the Arctic to Antarctic. They may accumulate at remote locations such as mid-ocean gyres, as well as close to population centres and shipping routes.

Fish and shellfish ingest microplastics and they have been found in a variety of commercial fish and shellfish in retail outlets. Further research is needed in order to determine how and if microplastics pose a risk for food safety and potentially food security.

The good news is that several governments have announced plans to ban microbeads in cleaning products and cosmetics, such as exfoliating facial and body scrubs, and a number of cosmetic companies have already made voluntary commitments to phase them out by 2020.

Microplastics have come to the attention of the Joint Group of Experts on Scientific Aspects of Marine Environmental Protection (GESAMP), which is an advisory body of the United Nations, for which IMO fulfils Secretariat functions.

The GESAMP working group on microplastics has produced two reports. The second microplastics report , published in January 2017, investigates the sources and fate and potential ecological impacts of microplastics and gives recommendations for further work.

What has IMO done to regulate marine litter?

IMO pioneered the prohibition of plastics’ disposal from ships anywhere at sea almost 30 years ago.

Garbage includes all kinds of food, domestic and operational waste, all plastics, cargo residues, incinerator ashes, cooking oil, fishing gear, and animal carcasses generated during the normal operation of the ship and liable to be disposed of continuously or periodically.

MARPOL Annex V applies to all ships, which means all vessels of any type whatsoever operating in the marine environment.

MARPOL Annex V recognizes that some sea areas require higher degrees of protection and can be designated as Special Areas under MARPOL.

Currently, there are eight Special Areas designated under Annex V: the Mediterranean Sea, the Baltic Sea, the Black Sea, the Red Sea, the "Gulfs" areas, the North Sea, the Wider Caribbean region including the Gulf of Mexico and the Caribbean Sea, and the Antarctic area.

All of these have entered into effect, except the Black Sea and the Red Sea (due to no receipt of sufficient notifications on adequate reception facilities).

You can see the different types of garbage covered by Annex V here . There is a complete prohibition on plastics, domestic wastes, cooking oil, incinerator ashes, operational wastes and fishing gear. For other types of garbage, such as food wastes, there are specific rules on when and where they can be discharged.

Avoiding single-use plastic

Guidelines adopted by IMO recommend that "all shipowners and operators should minimize taking on board material that could become garbage". Specifically, the guidelines recommend that shipowners and operators, where possible with the ships suppliers, should consider the products being procured in terms of the garbage they will generate. Options include:

• using supplies that come in bulk packaging, taking into account factors such as adequate shelf-life (once a container is open) to avoid increasing garbage associated with such products;
• using supplies that come in reusable or recyclable packaging and containers;
• avoiding the use of disposable cups, utensils, dishes, towels and rags and other convenience items whenever possible; and
• avoiding supplies that are packaged in plastic, unless a reusable or recyclable plastic is used.

The guidelines recommend that manufacturers, cargo owners, ports and terminals, shipowners and operators and governments consider the management of garbage associated with ships' supplies, provisions, and cargoes as needed to minimize the generation of garbage in all forms.

Download the guidelines here. (Resolution MEPC.295(71) 2017 Guidelines for the implementation of MARPOL ANNEX V).

Placards, garbage management plans and garbage record-keeping

Ships (12 metres or more in length) and fixed or floating platforms are required to display placards which notify the crew and passengers of the discharge requirements.

Ships (100 gross tonnage and above) or those carrying 15 or more persons and fixed or floating platforms must carry a garbage management plan which the crew should follow. Larger ships (400 gross tonnage and above) or those carrying 15 or more persons must keep a Garbage Record book, to record every permitted discharge into the sea or to a reception facility, competed incinerations and so on.

Port reception facilities

The effectiveness of ships to comply with the discharge requirements of MARPOL depends largely upon the availability of adequate port reception facilities, especially within special areas. Hence, the Annex also obliges Governments to ensure the provision of adequate reception facilities at ports and terminals for the reception of garbage without causing undue delay to ships, and according to the needs of the ships using them.

IMO has issued a circular ( MEPC.1/Circ.893, July 2021 ), reminding Parties to MARPOL Annex V of their obligation under regulation 8 of MARPOL Annex V to ensure the provision of adequate facilities at ports and terminals for the reception of garbage, including plastic waste from ships and fishing gear. 

Global action on marine litter

IMO is working with other UN organizations to highlight the issue of marine litter and promote global action to tackle it.

In 2023,  World Environment Day  was centred on the theme #BeatPlasticPollution. The day - held annually on 5 June - is led by the United Nations Environment Programme (UNEP). 

UNEP also runs the #CleanSeas campaign. See more  here  and watch the marine litter  video .

IMO is one of the partners in the Global Partnership on Marine Litter ( GPML ), which is managed by UN Environment, with IMO co-leading on sea-based sources of marine litter together with the Food and Agricultural Organization (FAO).

Under this partnership, several activities have been undertaken, including the development of a training package on MARPOL Annex V and port reception facilities and a review of plastics in the waste streams under the London Convention and Protocol.

IMO has contributed to the development of the Massive Open Online Course ( MOOC ) on Marine Litter. The MOOC has been created in order to stimulate leadership and offers opportunities for actionable and change oriented learning related to marine litter.

Dumping of wastes at sea

The dumping of wastes at sea is regulated by the 1972 Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, commonly called the London Convention, and its 1996 Protocol. Under the 1996 Protocol, it is prohibited to dump wastes at sea from ships or aircraft, except for those on a permitted list, for which a special permit may be sought, and only as after a careful assessment of other disposal options and potential impacts.

The list of possibly allowed wastes includes dredged material, sewage sludge, fishing wastes, inert inorganic geological material, organic material of natural origin and carbon dioxide streams from carbon capture and storage projects. Any such waste must be thoroughly assessed before a permit is given.

IMO performs the Secretariat functions for the London Convention and Protocol.

The Contracting Parties have completed a review of the state of knowledge with respect to how the dumping of wastes may contribute to the presence of marine litter, in particular plastics, in the marine environment. Dredged materials and sewage sludge are thought to be the most likely of the waste streams to contribute to the presence of marine litter. Download the report.

In 2016, the Contracting Parties, acknowledged the significant quantity of marine litter entering the ocean and the severe and long-lasting threat it poses to the marine environment, and adopted a recommendation to encourage action to combat marine litter (see full statement here ). The Parties also noted the problem of abandoned fibreglass vessels in the marine environment, and agreed to investigate the issue further.

Download: The London Protocol – what it is and why it is needed .

Recycling ships

When a ship itself reaches its end of life, almost every part of a ship can be recycled - steel, machinery, equipment, fittings and furniture. Virtually nothing goes to waste and the materials and equipment are almost entirely reused and recycled. Moreover, ship recycling provides direct and secondary employment for thousands of workers, both in the industry itself and in the ancillary markets for materials and components, particularly in the five countries where most of the world’s ship recycling is carried out today – Bangladesh, China, India, Pakistan and Türkiye.

IMO has embraced the regulation of ship recycling  - not only for ships, but also for land-based recycling facilities - into a single, comprehensive instrument. The International Convention on the Safe and Environmentally Sound Recycling of Ships, the so-called Hong Kong Convention, was adopted in 2009.

The Convention embraces the “cradle to grave” concept for the purpose of addressing all environmental and safety aspects relating to ship recycling, taking them into account from the ship design stage onwards and right through to the end of the ship’s life, and including also the responsible management and disposal of associated waste streams in a safe and environmentally sound manner.

When the Hong Kong Convention enters into force, it will provide inclusive and effective standards that can be applied universally. It places responsibilities and obligations on all parties concerned - shipowners, ship building yards, ship recycling facilities, flag States, port States, recycling States, etc. The Convention, the first ever to address ship recycling issues, is aimed at ensuring that ships, when being recycled after reaching the end of their operational lives, do not pose any unnecessary risk to human health and safety or to the environment.

IMO is currently raising awareness of the Convention internationally and in particular is working with recycling countries, to help build the capacity and establish the conditions that will enable them to ratify/accede to the Hong Kong Convention.

Mandatory reporting of lost containers  

IMO has adopted amendments to MARPOL Protocol I, referencing a procedure for reporting lost freight containers ( see MEPC 81 ). Containers lost overboard can be a serious hazard to navigation and safety at sea as well as to the marine environment. 

The amendments to article V of Protocol I of the MARPOL Convention (Provisions concerning reports on incidents involving harmful substances) would add a new paragraph to say that "In case of the loss of freight container(s), the report required by article II (1) (b) shall be made in accordance with the provisions of SOLAS regulations V/31 and V/32." The amendments are expected to enter into force on 1 January 2026.  

Related draft SOLAS chapter V amendments are set to be adopted by the Maritime Safety Committee (MSC 108), in May 2024, and will require the master of every ship involved in the loss of freight container(s) to communicate the particulars of such an incident to ships in the vicinity, to the nearest coastal State and to the flag State. 

Carriage of plastic pellets by sea in freight containers 

IMO began addressing the issue of the transport of plastic pellets following the X-Press Pearl incident off the coast of Sri Lanka in February 2021. Following a fire onboard and subsequent sinking of the ship, pellets were released into the marine environment and several tonnes of pellets washed ashore. 

In March 2024, IMO's Marine Environment Protection Committee ( MEPC 81 ) approved Recommendations for the carriage of plastic pellets by sea in freight containers. The recommendations address packaging; transport information; and stowage of plastic pellets. Find out more on our FAQ page on plastic pellets.

Studies and reports

How to monitor plastics in the oceans

Guidelines for the monitoring and assessment of plastic litter and microplastics in the ocean - A set of publicly-available guidelines for monitoring plastics and microplastics in the oceans will help harmonize how scientists and others assess the scale of the marine plastic litter problem. The guidelines can be used by national, inter-governmental and international organisations with responsibilities for managing the social, economic and ecological consequences of land- and sea-based human-activities on the marine environment. The Guidelines for the monitoring and assessment of plastic litter and microplastics in the ocean have been published by the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP)

The full set of guidelines is available to download free-of-charge from the GESAMP website here .

Plastic fibre boats - What can be done with small recreational boats at the end of their lives?

Dumping them at sea is not a good solution. Download the study End-of-life management of fibre reinforced plastic vessels: alternatives to at sea disposal here .

Hull scrapings and marine coatings as a source of microplastics

Literature review to assess current knowledge and data regarding marine coatings as microplastics sources. The study identifies important data gaps and made suggestions for subsequent research into whether ship coatings are an important source of microplastics to the ocean. Download the study, Hull scrapings and marine coatings as a source of microplastics here .

Microplastics in the Marine Environment

The comprehensive report on 'Sources, Fate and Effects of Microplastics in the Marine Environment: Part 2 of a Global Assessment' expands on an earlier study published in 2015. Sources and fate of potential ecological impacts of microplastics are investigated in greater depth and recommendations for further work are included.

Download Sources, Fate and Effects of Microplastics in the Marine Environment (Part 2) here.

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Is Zero-Waste Travel Actually Even Possible?

Travelers today are more conscious of their environmental footprint, even if it often seems abstract. but what about the trail of waste travelers create.

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Todos Santos is beloved for its rugged coastline and water.

Josh Withers/Unsplash

The shimmering emerald cove beckons; reaching it requires a trek up the cacti-dotted cliffs under the Baja sun, then a scramble across boulders on a small beach. But if you arrive at the right time, the water is calm enough for a swim, and you may spot sea lions on the rocks or a whale in the distance. You might also, unfortunately, see a few plastic bottles.

This popular trail in Todos Santos, Baja California Sur, became a favorite of mine during the nearly two years I was based there. Now the small town is grappling with the effects of enchanted visitors who end up staying (hello, me), and it’s trying to avoid going the way of other overdeveloped coastal areas—ones without the infrastructure to support rapid growth, thus ending up with overflowing landfills and waste that leaches into the ocean (hello, Tulum).

“How do we prevent ourselves from becoming just another overrun beach town?” Bryan Jáuregui says. She’s a founding member of Alianza Cero Basura - Zero Waste Alliance , a community-led initiative to implement a plan for a zero-waste future for Todos Santos and the neighboring town of El Pescadero. Jáuregui’s question has urgency: These towns are located in Baja California Sur, the least populated but fastest-growing state in Mexico. As the co-owner of Todos Santos Eco Adventures and Los Colibris Casitas boutique hotel, she calls it “enlightened self-interest” to take on her town’s waste problem.

This tension is not unique to Baja. Around the world, destinations are struggling to balance tourism and economic growth for locals while protecting their natural resources. And even though travelers are more conscious of their environmental footprints than ever, what can they realistically do about them? Is leaving behind zero waste during travel even possible?

Born out of the 1970s ethos of environmental advocacy, the zero-waste movement is focused on sending as little material waste to landfills as possible. The “five Rs” of a zero-waste lifestyle, coined by Bea Johnson in her book, Zero Waste Home , are the movement’s mantra: refuse, reduce, reuse, recycle, and rot (i.e., compost).

A growing number of individuals are embracing these concepts at home: They are eschewing single-use plastics, purchasing bulk items at grocery stores, and taking their food scraps to community compost centers. It gets harder, however, to keep this mindset on the road: Most travelers eat out for most meals and, depending on where they go, don’t necessarily have access to potable drinking water. Travelers are inherently overconsumers.

In some places, tourists generate up to twice as much waste as residents due to the packaged goods they buy, including travel-size toiletries. Eight out of 10 tourists visit coastal areas, contributing to the 8 million tons of plastic that enters oceans and kills 100,000 marine animals a year, according to the United Nations Environment Programme. But it’s more than plastic; often overlooked is food waste. The hotel industry alone produces 79,000 tons of food waste yearly. Cruise ships can generate about 1.3 pounds per person per day on average . Cutting down can make a significant difference, says Vishal Kumar, CEO of Waste Warriors , a nonprofit in the Indian Himalayan Region.

“The creation of less waste means less demand for the production, packaging, and distribution of goods, which results in reduced greenhouse gas emissions throughout the value chain,” Kumar says. When organic waste is dumped into landfills, it releases methane, which has 20 to 80 times more global warming potential than CO2. Aiming for zero waste, then, is a climate solution.

We don’t need 12 people doing zero waste perfectly each year. We need 12 thousand, or 12 million people doing it imperfectly.

In 2007, Natural Habitat Adventures eliminated plastic water bottles from their trips and became the world’s first carbon-neutral travel company. It then took on another ever-growing environmental issue: waste.

Twelve years later, in July 2019, the company led the world’s first zero-waste trip in Yellowstone National Park. To divert 99 percent of the trip’s waste—which would otherwise end up in a landfill—guests carried bamboo cutlery that they washed between meals and a compost bucket for all uneaten food scraps.

While Natural Habitat Adventures isn’t leading 100 percent zero-waste adventures anymore, that doesn’t mean the experiment failed. “We learned that zero waste is possible. However, it is indeed very resource- and time-intensive,” says Court Whelan, chief sustainability officer of Natural Habitat Adventures , of the 18 months researching and planning for the trip.

“I don’t think the extreme confines of zero-waste travel is the end goal. I think examples of zero waste, whether it’s on a certain trip or camp, leave an inspirational echo across the industry.” It’s more about instigating change, and any “waste-lessening movement” is moving toward the goal line, he adds.

“We don’t need 12 people doing zero waste perfectly each year. We need 12 thousand or 12 million people doing it imperfectly.”

One of the best ways travelers can work toward a zero-waste mindset on the road is to dig deeper into where their dollars are going.

Alianza Cero Basura created a way for travelers to support businesses in Todos Santos and El Pescadero that self-assess their waste-reductions impact with a directory of Waste Wise All Stars . Beyond using this guide to find local restaurants and hotels actively working to reduce their waste, travelers can fill up their water bottles at one of Alianza’s refill stations installed throughout town. Alianza also created the first community-led organic waste farm and research center in Baja California Sur; it produces soil-enhancing products and compost, diverting 60 percent of the town’s organic waste from the landfill.

Meanwhile, Norwegian cruise company Hurtigruten—which banned single-use plastics in 2018 and has introduced zero-emissions vehicles and hybrid-powered cruise ships—in April 2024 launched a zero-edible-food-waste program with a goal to, well, reduce food waste to zero grams per guest. Edible food waste from Hurtigruten’s Original Coastal Express ships, which sail along the coast of Norway, will be composted and sent to a local farm that will use it to cultivate products that Hurtigruten will use in its menus. “Farm to fleet to farm” is its goal.

Still, the most obvious and easiest way to create less waste is by refusing. Consider: The more things we acquire, the more things will become waste. On the road, think about what you need. Can you split dishes with your fellow travelers? Get bulk snacks for your road trip? Share some gear instead of everyone packing their own?

Another simple habit is employing reusables—and not just a water bottle. You can buy a zero-waste travel kit , or make one of your own, which could include a reusable tote bag (I carry my trusty Baggu bag on every trip); a reusable silverware kit that doesn’t look like camping gear; and bags and capsules to carry toiletries. My collection of silicone Stasher bags are for more than packing snacks; I use them to carry all my toiletries, which are poured into my magnetic, stackable Cadence Refillable Travel Capsules .

Pack light, and pack items that have multiple uses. Not only does doing so lessen your carbon footprint, but also it can save your sanity and budget. Instead of buying new gear for every trip, consider renting or buying used gear: On a ski trip in Aspen this year, I rented ski pants from Suit Yourself , a mobile ski clothes outfitter. Kit Lender rents outdoor gear and apparel, and Patagonia and REI let you buy and sell your clothing . (Check out AFAR’s guide to places to buy used clothing gear .) Root Adventures also discourages buying new gear by offering a subsidy for any pretrip gear repair, and it includes gear rentals in the trip price.

Mindsets change— maybe not overnight, but slowly, actions create momentum and conservation culture grows. One of the best ways to do this is to let your dollars do the talking, Whelan says. “Single-use is technically easier. Are we happier people because we are consistently able to make and do the easiest thing possible?”

Zero-waste travel is indeed complicated to attempt and even more difficult to adopt perfectly. When we travel, we’re always pushing ourselves—to climb that mountain, to make that plane connection, to attempt that phrase in Spanish. When we put the effort in, we’re rewarded. Leaving nothing behind is just another mindset to get used to.

Do Cruise Ships Dump Trash in the Ocean?

There is no doubting cruise ships accumulate a lot of waste, but what happens to it? 

Do they bring it all back to shore, or is some or all of the garbage dumped in the sea?

We know more than our oceans are precious, and with more and more cruise ships on our seas and seemingly getting ever larger, it’s well worth taking a look to find out the real answer.

Firstly, let’s look at what cruise ships should be doing with their trash.

Can Cruise Ships Dump Trash in the Ocean

It’s clear from Marpol guidelines that cruise lines cannot dump their trash into the oceans.  This includes all types of plastics, metal, glass, crockery, rags, paper, packaging materials, and incinerator ashes.

The regulations are governed by Marpol, and in the case of trash-related waste from cruise ships, they have to adhere specifically to Annex V (source pdf)

In this section, we focus on nonfood trash.

“Annex V Prevention of Pollution by Garbage from Ships” states that cruise ships need to follow the following guidelines which clearly state the following garbage should not be dumped into the sea in any water, special, arctic, or otherwise.

Prohibited Garbage Items for all waters :

• Cooking oil,
• Fishing gear
• Floating dunnage
• Incinerator ashes
• Lining and packing materials
• Plastic garbage bags
• Synthetic ropes

and similar refuse.

Dumping any of these types of garbage items in the seas would be illegal.

Note we have covered separately how cruise ships dispose of human waste and what cruise ships do with food waste , both also cover the processes involved.

Do Cruise Ships Dump Trash In the Ocean

We have established that it’s illegal for cruise ships to dump their trash into the ocean.  

However, do they dump it anyway?  

Most cruise ships do not dump their trash in the oceans.  Stringent records of various waste types are kept, including what is removed from the ships, and its weight is monitored to spot any discrepancies.

If ships were dumping waste at sea, it would be noticed when the weight of particular waste types they removed would be a lot less than expected.

While some cruise ships have been caught dumping garbage, they were punished with heavy fines, which hopefully act as a  significant deterrent against future dumping.

In 2019 Carnival Corporations Princess Cruise lines were fined $20 million in part for dumping plastics into the waters of the Bahamas.  

They were already on probation from 2016 when they were fined for Princess Cruises dumping oil waste on an ongoing basis for several years. Source: NYT  

What do Cruise Ships do with all their Garbage?

Where do cruise ships empty their waste.

Cruise ships are only legally allowed to dump food and human waste into the sea after it has been processed to certified safe levels.

All other waste is separated into waste-type categories, compacted, and stored until it can be removed from the ship when it returns to port and, as much as possible, taken to be recycled or, in some cases, sent to a landfill.

How Cruise Ships Are Reducing Their Waste

Cruise ships have banned single-use plastics, such as straws, which is why taking your own reusable straw is one of our cruise essentials for some people.

Passengers are encouraged to put trash in the correct recyclable trash can.  Even the crew are encouraged to make sure their waste is recycled, and as an added incentive Royal Caribbean out any rebates earned from recycled waste into their retirement program.

Royal Caribbean – Zero Landfill Ship

One of the Royal Caribbean’s largest ships the Symphony of the Seas is claimed to be a zero landfill ship.

On deck 2, the cruise ship has a dedicated waste and recycling center.

Trash cans are checked for recyclables which split into 4 main categories:

• Cardboard and paper – compacted into bundles
• Glass – sorted into colors and crushed
• Metal – sorted into types and compacted in a bailer
• Plastic – compacted

The compacted bundles are stored by waste type until they can be emptied when the cruise dock is in its home port.

All the recyclable materials are removed and transported to local recycling partner sites.

Cruise Line Environmental Credentials

There is no doubt that cruise ships have an impact on the environment, and cruise lines should consider taking all actions necessary to preserve the environments in which they sail.

The bare basics should be factors they can control, like responsible onboard waste management.

To work out which cruise lines and individual cruise ships are the most environmentally friendly, Friends of the Earth have compiled a “ Cruise Ship Report Card ” to give an indication of which ones are the best for the planet.

Each cruise line and ship is rated A-F, or ungraded for the following:

• Sewage Treatment
• Air Pollution Reduction
• Water Quality Compliance

In 2022 the top 3 cruise lines by final grade were:

• Regent Seven Seas Cruises
• Disney Cruise Line 
• Oceania Cruise Line

The top cruise ship was Disney Wonder with an A-

All 4 Disney cruise ships at the time (there are now 5 ships in the fleet) were in the top 6.

Frequently Asked Questions

Do cruise ships dump plastic into the ocean.

It is illegal for cruise ships to dump any kind of plastic into the sea.   Plastic can take hundreds of years to degrade and, in the meantime, pollute our oceans by killing turtles who mistake plastic garbage bags,  as a food source filling whale’s stomachs so much they can’t eat enough real digestible food down to microplastics infiltrating all manor or marine life no matter how small.

Unfortunately, some cruise ships have been caught dumping plastic waste.

Does Carnival Dump Trash In The Ocean?

Carnival cruise has been found guilty of dumping plastic in the oceans and was fined $20 million in 2019.

By law, they should not be dumping trash into the ocean.

Related Posts

What is the Draft of a Cruise Ship? (and Why Does it Matter?)

How Many Doors on a Cruise Ship? (Yes, I Counted)

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Is This a Picture of a Cruise Ship Dumping Human Waste Into the Ocean?

Apparently it's difficult to tell the difference between sand, mud, and human excrement from a distance., published feb. 1, 2019.

About this rating

An image supposedly showing a cruise ship dumping human waste into the ocean near a coastal city is frequently shared on social media. One popular iteration with more than 30,000 shares was posted by Facebook user Mena Anjos on 19 January 2019 along with the caption (translated via Google) "You know what this is? It's the discharges from the floating cities they call cruise ships":

A number of social media users commented and shared this image with more explicit descriptions of what it supposedly showed:

You know what this is? It's the discharges from the floating cities they call cruise ships...but it’s ok because tourism...looks like terrorism to me... The cruise ship @MSCCrucerosArg discharging its sewers in the port of Punta del Este... This is a cruise ship dumping excrement. You know what this is? It's the discharges from the floating cities they call cruise ships. Disgusting! Boycott until they discharge at port into a waste water treatment facility!

This is a genuine photograph showing two dark, brownish clouds in the waters surrounding a cruise ship, but it doesn't document that ship's dumping human waste into the ocean. Rather, it captures a cruise ship dropping anchor off the coast of Punta del Este, Uraguay.

After this image went viral in January 2019 (along with its unsavory claims about waste and pollution,) Alejandro Nario, Uruguay's National Director of the Environment ( Dinama ), took to Twitter to explain what the photograph actually depicted. According to Nairo, this image captured the cruise ship's starting up its turbines before dropping anchor, and thus the brown clouds visible in the water are sand and mud churned up from the water's bottom, not clouds of human excrement:

Ante consultas recibidas sobre esta imagen, aclaramos: fue tomada en el momento que están acomodando el barco para fondear, las turbinas de arranque producen turbulencia con las hélices, levantando arena y barro del fondo, en una zona de poca profundidad No se trata de efluentes pic.twitter.com/e2LQnTaG5W — Alejandro Nario (@alejandronario) January 11, 2019

How do these cruise ships, which can carry thousands of passengers and crew members on multi-day trips, actually dispose of their waste? A 2017 article from the Telegraph explained:

According to environmental regulatory lead at Royal Caribbean International, Nick Rose, the idea that cruise lines go round dumping stuff in the ocean is just wrong. “Our multi-stage treatment systems exceed the requirements of all international regulations,” he says. This is how it is done. For a start, there’s a lot of liquid to deal with every day. Even with aeration systems designed to reduce the amount of water coming out of bathroom taps and shower heads, the average ship will use average of 40-50 gallons per passenger per day. The “grey water” from galleys, laundries and bathrooms is first mixed in carefully measured proportions with the “black water” lavatory waste before bio reactors deep in the bowels of the ship set to work. There, all the nasty stuff is filtered out and digested by bacteria. The remaining liquid is disinfected by UV radiation rather than chlorine or other chemicals that would themselves be harmful to marine life. At this stage, and having been monitored for any remaining bugs such as faecal coliform, it is discharged into the sea “cleaner than the seawater that it might have started out as before being desalinated,” according to Rose. Because it is so clean, some ports have given approval for it to be discharged closer than the statutory 12 miles from land. About three tons of solids left from the original 1,200 tons of waste per day is incinerated or contained until it can be offloaded.

El Pais .   "¿Qué Son Esas Manchas Que Se Ven Desde lo Alto Alrededor de Los Cruceros en El Este?"     11 January 2019.

Honeywell, John.   "What Happens When You Flush the Loo on a Cruise Ship?"     Telegraph .   1 February 2017.

By Dan Evon

Dan Evon is a former writer for Snopes.

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China stopped taking our plastic. Now America is drowning in it.

America has long had a plastic problem. It's an urgent question — what do we do with the 40 million tons of plastic waste we produce annually? One year of plastic waste is roughly enough to smother the entirety of Manhattan a meter deep, and it has to go somewhere. For years, the answer was simple: Make a lot of it, dump most of it in the landfill, and make the rest of it someone else's problem — the US regularly exported 7 million tons a year to China alone. Some of it was melted into lesser plastic; the rest was incinerated or buried.

But then, in 2018, China cut off plastic imports.

Now, America is coming to terms with a hard truth: Plastic was never designed to be recycled and there's no profitable way to recycle 91% of it. The environmental impacts have been disastrous. About 430 million tons of plastic are produced globally every year, accounting for 14% of global oil demand. The refinement of plastic alone emits up to 235 million tons of greenhouse gases a year. Most of that plastic breaks down into microplastics that make their way into the air, rain, and our bodies . Almost 95% of America's water supply contains plastic fibers.

While the US, the UK, and other European countries responded to China's ban by sending their waste to places like Thailand and Malaysia, those countries then followed China in cutting off waste imports. The message was clear: The Global South would no longer be a dumping ground for the West.

This isn't sustainable, Tim Miller, a vice president at the Ohio plastic-recycling center Royal Paper Stock, told me, adding: "But I don't know how to stop it." Pyrolysis is another sign of America's plastic paralysis.

In the years after World War II, plastic flooded the marketplace as a cheap alternative to otherwise scarce and finite materials. It was hailed as a democratic harbinger of a new, utopian age of capitalism, fueling the subsequent decades of cheap consumerism that became synonymous with the American dream.

"The continuous flow of oil fueled not just cars but an entire culture based on the consumption of new products made of plastics," Susan Freinkel wrote in her book "Plastic: A Toxic Love Story."

Plastic went from being practically nonexistent in 1940 to being consumed at a rate of 30 pounds a person each year by 1960. Just as quickly, it became a target of environmental movements protesting litter, garbage-filled oceans, and landfills brimming with plastic. Oil and chemical companies responded by looking into whether recycling was realistic or, more importantly, profitable. It wasn't . So companies shifted the blame for the pollution onto consumers. The "Crying Indian" commercial, funded by beverage and packaging corporations, aired in 1971, showing a Native American character crying at the sight of litter.

The messaging worked. As companies expanded plastic into every facet of life, recycling became the due diligence needed to sustain our hyperconsumption. We didn't worry about plastic bottles because the recycling truck carried them off to a new life. Companies like Coca-Cola and Nestlé slapped "100% recycled" and "100% recyclable" labels on their packaging to appear sustainable. Just last year, the Plastics Industry Association launched a million-dollar ad campaign, "Recycling Is Real," claiming that it's "not only real, but feasible and economical."

While recycling is real, the vast majority of plastic isn't recycled, mostly due to how expensive it is to clean and sort it effectively. A 2022 report by the Organization for Economic Co-operation and Development found only 9% of all plastic ever produced had been recycled; 72% ended up in landfills or the environment. Unlike aluminum or glass, the plastic that can be recycled rarely results in replacing one recycled water bottle with another.

Instead, it's a process of downcycling — turning plastic into lesser plastics like plant containers or bins before they are relegated to a landfill. By downcycling a tiny portion of plastic waste, companies can genuinely reuse a relatively small share of plastic, while convincing consumers that the industry has created a circular economy of infinitely recycled plastic. Never mind that products advertised as being made from recycled plastic are made almost entirely out of new plastic or that almost all the 300 pounds of plastic every American consumes each year (10 times as much as in 1960) ends up in a landfill, in the ocean, or incinerated.

Larry Thomas, a former president of what's now called the Plastics Industry Association, told NPR in 2020: "If the public thinks that recycling is working, then they are not going to be as concerned about the environment." And if they aren't worried about the impact of plastic on the environment, they won't threaten the plastics industry.

Since 2018, the fossil-fuel and plastics industries have faced two harsh realities: Oil is being phased out in favor of clean, renewable energy, and plastic waste can no longer be exported to developing nations in the South. To replace their fuel losses, oil companies are going all in on plastic. The International Energy Agency predicted in 2018 that petrochemical products like plastic would outpace trucks, aviation, and shipping in oil demand by 2050. In a recent report, ExxonMobil predicted that petrochemicals used largely for plastics and fertilizer would account for nearly all of the oil industry's growth by 2050, replacing industrial fuel demand, which is projected to decrease. To keep expanding plastic production, however, it needs to look sustainable.

Akron, Ohio, which hosts about one-quarter of the country's polymer companies, is ground zero for this push. Designated by the Biden administration as the only "tech hub" in Ohio, the city has received tens of millions of dollars from the CHIPS Act, which it hopes to use to create a circular economy around plastic.

In 2012, Alterra Energy opened America's first large-scale plastic-pyrolysis facility. According to its website, Alterra converts "plastics back into their original building blocks to produce new plastics and other valuable products." The crude oil produced by the Akron facility is shipped to petrochemical companies around the globe to be purified and made into new plastics. But it's unclear how effective this process is.

A study published in 2023 by researchers at the National Renewable Energy Laboratory found that the economic and environmental impact of turning pyrolysis oil back into plastic was actually far worse than it was to make brand-new plastic. As a result, they said, pyrolysis oil is "typically reintegrated into the petrochemical industry where only a small fraction is used for closed-loop recycling."

"It has had, let's say, limited success," Miller, the Royal Paper Stock vice president, said about pyrolysis. "No one yet in the United States that I know of is just cranking in plastic and pumping out oil." He pointed to a pyrolysis facility in Oregon that just announced it would shut down after tens of millions of dollars in losses.

Residents in Akron are split on the impacts of the Alterra facility. On the one hand, pyrolysis melts plastic to be reused instead of sending it to the landfill or incinerator. On the other, it emits cancerous pollutants such as mercury, benzene, and arsenic, and props up the very fossil-fuel companies that are driving the climate crisis.

"Akron's going for 'the green city on the hill,'" Kelley Sayre, a fourth-generation Akron resident, told me, "but it's really 'the greenwashing city.'"

Vicky Abou-Ghalioum, the lead petrochemicals organizer of Buckeye Environmental Network, has been working with Akron residents concerned about the environmental and health impacts of chemical recycling, but it's proved challenging in a city ruled by polymers. "People are afraid to talk about plastic," she told me. Her organization has been pushing the EPA to address the influx of planned pyrolysis facilities in Ohio, arguing that they're bad for the environment and people, and aren't even profitable.

In a statement to Business Insider, Alterra Energy said its Akron facility is profitable and diverts over 100,000 pounds of plastic each day from landfills. "We operate in a heavily regulated industry and are in compliance with those requirements," the company said in response to concerns about toxic emissions. It also said one of its customers uses Alterra's oil product exclusively for making new plastic.

Despite the problems of pyrolysis, many manufacturers hail it as a sustainable miracle. Companies such as Eastman Chemical Co. see chemical recycling as the solution to recycling or composting 50% of their plastic packaging by 2025, and the American Chemistry Council claims the growing industry is necessary for fostering what it calls " plastics circularity ." But these companies face an uphill battle. Former Mayor Mike Bloomberg of New York City launched an $85 million campaign in 2022 to stop over 120 proposed petrochemical facilities. "Petrochemical plants poison our air and water — killing Americans and harming the health of entire communities," Bloomberg said in a statement.

In the plastic-recycling industry, pyrolysis is seen as a well funded but failing experiment. A 2023 report by Beyond Plastics and the International Pollutants Elimination Network found that the 11 pyrolysis facilities in operation in the US required massive public subsidies, most couldn't operate at full capacity, and only two of the plants sold the crude oil to be used exclusively for plastic production. Most of it was sold to make fuels and chemicals. Based on their findings, they argued that pyrolysis was ultimately "a public relations distraction to prevent plastic regulation and prop up the profits of the petrochemical/plastics industry."

Though the conundrum of plastic grows more dire by the day, there are signs of hope. In early 2022 , the UN adopted a resolution that could send shock waves throughout the entire plastic-disposing world. Heads of state, environment ministers, and UN representatives agreed to end all plastic pollution with a legally binding international plastic treaty to be officially adopted later this year. "Plastic pollution has grown into an epidemic," Espen Barth Eide, Norway's then-minister for climate and the environment, said in the announcement. "With today's resolution we are officially on track for a cure."

The resolution would establish an agreement addressing plastic at every level, from production to recycling, in an attempt to reduce plastic pollution worldwide. Organizations such as the international coalition Break Free From Plastic have said that cutting the production of plastic has to be on the table. "The oil and gas industry sees plastic as its primary growth market and is investing billions of dollars in new and expanded facilities," the organization wrote in a 2022 statement. The group recommended bans on single-use plastics, a plastic tax, and regulations that prioritize plastics that can be recycled.

"Reduction in the production of plastic is entirely possible," Abou-Ghalioum of Buckeye Environmental Network told me. She pointed to the more than 500 cities and 12 states that have banned plastic bags, reducing the number of bags used by the billions. "It's talked about how we rely on plastic for so many things, and it just feels like a marketing ploy to make us reluctant to shift away from it," she said. "We had everything we ever needed before plastic."

The tough reality is that the 9.5 billion tons of plastic with us will be here for hundreds of years. But how many millions of more tons are added will be determined by the types of solutions we arrive at today.

Taylor Dorrell is a writer and photographer based in Columbus, Ohio.

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