Marine litter
Marine litter presents a huge problem in our ocean, with some scientists warning that, by 2050, the quantity of plastics in the ocean will outweigh fish.
Marine litter refers to any long-lasting, human-made solid material that ends up in the ocean or along coastlines. It has been recognized as a threat to ocean health since the 1970s, leading to international regulations to help prevent its spread.
Plastic litter poses a particular concern because of its incredible strength and durability, meaning it can stay in the ocean for decades or even centuries, making it one of the most persistent threats to marine life.
IMO has been regulating marine litter for the last 50 years, from operational discharges from ships to the dumping of waste at sea. More recently, IMO has concentrated its efforts to tackle the issue of plastic marine pollution.
IMO’s Action Plan to Address Marine Plastic Litter from Ships was updated in 2025. It sets out a range of ambitions to reduce marine plastic litter generated from, and retrieved by, fishing vessels.
IMO implements the OceanLitter Programme aimed at supporting developing countries to act against marine plastic litter from shipping and fisheries.
What is marine litter and why is it detrimental?
Marine litter is human-made solid waste that ends up in the ocean or along coasts. It can be deliberately dumped, carried by rivers, wind or sewage, lost at sea (like fishing gear or cargo) or left behind on beaches.
Marine litter, including plastics and microplastics, is known to result from land-based sources in massive quantities but can also originate from ships and fishing activities. It can include, among others, domestic and operational waste, cargo residues, incinerator ashes, cooking oil or fishing gear.
As of 2021, UN Environment estimated that the oceans contained between 75 and 199 million tons of plastic. Without urgent action, the amount of plastic waste entering aquatic ecosystems could triple by 2040 compared to 2016, reaching 23–37 million tons each year.
Marine litter causes a wide spectrum of environmental, economic, safety, health and cultural impacts. Floating garbage and plastics can be a navigational hazard and become entangled in propellers and rudders of ships.
Sea creatures can become trapped inside containers or strangled by nets or ropes. Microplastics can also enter the food chain as they are indigestible when swallowed.
Marine litter can be transported over large distances and can burden communities that are not responsible for its generation.
The Joint Group of Experts on Scientific Aspects of Marine Environmental Protection (GESAMP), an advisory body of the United Nations, published two studies (2015 and 2016) highlighting the existence of microplastics in the marine environment. IMO fulfils GESAMP’s Secretariat functions.
What has IMO done to regulate marine litter?
MARPOL Convention
IMO pioneered the prohibition of waste and plastics’ disposal from ships anywhere at sea almost 40 years ago with the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex V. Today, 156 countries have signed up to MARPOL Annex V.
Waste management
MARPOL Annex V prohibits the discharge of all types of garbage into the sea from ships, except in the cases explicitly permitted under the Annex. Since 1988, this treaty has prohibited the discharge of plastics, including discarded fishing gear, into the sea from ships.
Ships (12 metres or more in length) and fixed or floating platforms are required to display placards that notify the crew and passengers of the discharge requirements. Additionally, all ships of 100 gross tonnage and above, certified to carry 15 persons and more, or every fixed or floating platform must carry a garbage management plan on board. Resolution MEPC.220(63) provides the 2012 Guidelines for the development of garbage management plans.
Please find the different types of garbage covered by Annex V here.
Special Areas
MARPOL Annex V prohibitions apply to all ships, which means all vessels of any type operating in the marine environment, recognizing that some marine areas require higher degrees of protection and can be designated as Special Areas under MARPOL.
Currently, there are eight Special Areas: 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 designated areas have entered into effect except for the Black Sea and the Red Sea due to no receipt of sufficient notifications on adequate reception facilities.
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.
IMO reminds Parties to MARPOL Annex V (MEPC.1/Circ.893, July 2021) 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.
Single-use plastic
Guidelines adopted by IMO recommend that "all shipowners and operators should minimize taking on board material that could become garbage". Suggestions 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 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 Resolution MEPC.295(71) - 2017 Guidelines for the implementation of MARPOL Annex V here.
Mandatory reporting of lost containers
IMO has adopted amendments to the MARPOL and SOLAS Conventions on mandatory reporting of lost containers. Containers lost overboard can be a serious hazard to navigation and safety at sea as well as to the marine environment.
The amendments enter into force on 1 January 2026 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.
Plastic pellets
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, MEPC 81 approved MEPC.1/Circ.909 “Recommendations for the carriage of plastic pellets by sea in freight containers”. The circular provides guidance on packaging standards, the need for shippers to clearly share transport information identifying containers carrying plastic pellets and proper stowage methods.
A dedicated measure for the development of mandatory measures to reduce the environmental risks of plastic pellets transported by sea in freight containers was included in the 2025 Action Plan to Address Marine Plastic Litter from Ships (2025 Action Plan) (see below).
London Convention and London Protocol
IMO has also recognized the importance of preventing the dumping of various types of waste, including plastics, into the sea through the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 (London Convention or LC) and its 1996 Protocol (London Protocol or LP).
IMO performs the Secretariat functions for the London Convention and Protocol. Currently, 87 States are Parties to this Convention.
Its objective is to promote the effective control of all sources of marine pollution and to take all practicable steps to prevent pollution of the sea by dumping of wastes and other matters.
In 1996, the London Protocol was adopted to further modernize the Convention and, eventually, replace it. Under the Protocol, all dumping is prohibited, except for possibly acceptable wastes on the so-called "reverse list". The London Protocol entered into force on 24 March 2006.
Download: The London Protocol – what it is and why it is needed.
IMO Strategy to address marine plastic litter from ships
IMO’s Marine Environment Protection Committee (MEPC 83) adopted the 2025 Action Plan to Address Marine Plastic Litter from Ships (2025 Action Plan), identifying measures to be completed by 2030. The 2025 Action Plan, updating an earlier 2018 plan, is expected to be combined with the Strategy to address marine plastic litter from ships, adopted by MEPC 77 in 2021.
The Strategy 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 facilities and waste processing in reducing marine plastic litter.
The 2025 Action Plan and Strategy aim to:
Enhance public awareness, education and seafarer training
Improve understanding of the contribution of ships to marine plastic litter
Improve understanding of the regulatory framework associated with marine plastic litter from ships
Strengthen international cooperation
Promote targeted technical cooperation and capacity-building.
The Strategy and 2025 Action Plan support IMO’s commitment to meet the targets set in the UN 2030 Sustainable Development Goal 14 ( SDG 14 ) on the ocean by 2030.
Tracking progress: from the 2018 Action Plan to 2025
The initial Action Plan to Adress Marine litter from Ships provided IMO with a mechanism to identify specific outcomes and actions to achieve them in a way that is meaningful and measurable.
Following its initial adoption, a number of identified measures have progressed including:
2018 Action Plan measures | Developments |
Proposed study on marine plastic litter from ships | GESAMP report (2021): Publication of report “Sea-based sources of marine litter”, read. |
Looking into the availability and adequacy of port reception facilities | GloLitter Partnerships Project Knowledge Product: (2022): Publication of “Guidance Document on Developing Port Waste Management Plans”, read the document. (2023): Global IMO led webinar on how to develop a port waste management plan, watch the webinar. (2023): Publication of the “Guidance document on conducting techno-economic feasibility studies for the establishment of port reception facilities for plastic waste”, read the document. (2025): MARPOL Annex V E-Learning course, undertake the free course. |
Consideration of making marking of fishing gear mandatory, in cooperation with the FAO | MEPC 78 (2022): Majority of delegations supported making fishing gear marking mandatory under MARPOL Annex V. GloLitter Partnerships Project Knowledge Product (2023): Global IMO and FAO led webinar on the development of sea-based sources of marine plastic litter national policy and legislation, watch the webinar. Next Steps (2026): Member States are invited to submit proposals to the Sub-Committee on Pollution Prevention and Response (PPR 13) to amend MARPOL Annex V and prepare an MEPC circular promoting fishing gear marking systems and FAO Voluntary Guidelines. |
Promoting reporting the loss of fishing gear | MEPC 79 (2022): Adopted amendments to MARPOL Annex V (Resolution MEPC.360(79)), requiring ships of 100 GT and above to maintain a Garbage Record Book (previously, only required for ships over 400 GT). GloLitter Partnerships Project Knowledge Product (2022): Publication of the “Legal aspects of abandoned, lost or otherwise discarded fishing gear”, read the study. GloLitter Partnerships Project Knowledge Product (2022): Publication of “Report on Good Practices to Prevent and Reduce Marine Plastic Litter from Fishing Activities”, read the report. PPR 12 (2025): Advanced discussions on the establishment of an IMO-hosted database for reporting abandoned or lost fishing gear including ship, event and gear details with clarification on mandatory vs. voluntary fields. Next steps (2026): Member States and international organizations invited to submit detailed proposals on the reporting requirements to PPR 13. |
Facilitating the delivery of retrieved fishing gear to shore facilities | MEPC 79 (2022): Adopted amendments to MARPOL Annex V (Resolution MEPC.360(79)), requiring ships of 100 GT and above to maintain a Garbage Record Book, including entries for all discharges and accidental losses. GloLitter Partnerships Project Knowledge Product (2022): Publication of “Reporting and retrieval of lost fishing gear: recommendations for developing effective programmes”, to read the report. |
Reviewing provisions related to the training of fishing vessel personnel and familiarization of seafarers to ensure awareness of the impact of marine plastic litter | Underway as part of the comprehensive review of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers, 1978 (STCW Convention). |
Consideration of the establishment of a compulsory mechanism to declare loss of containers at sea and identify number of losses | MSC 108 (2024): Amendments to SOLAS Chapter V and MARPOL Protocol I (effective 1 January 2026) require ships to immediately report lost or drifting containers to nearby vessels, the nearest coastal State, and the Flag State, which must forward the information to IMO via GISIS. |
Enhancing public awareness | IMO continues to raise global awareness on protecting the ocean from marine litter through its OceanLitter Programme and related initiatives. Among others, this includes the 2025 World Maritime Day theme “Our Ocean, Our Obligation, Our Opportunity” and active participation at the 2025 UN Ocean Conference, led by the Secretary-General. |
Strengthening international cooperation, in particular with FAO and UN Environment (UNEP) | (2019): Establishment of IMO-FAO GloLitter Partnerships Project. (2024): Establishment of the IMO-FAO umbrella framework “OceanLitter Programme”, coordinating the GloLitter Partnerships Project, the RegLitter Project and the PRO-SEAS Project for wider impact. |
OceanLitter Programme to tackle plastic litter from shipping and fisheries
Led by IMO and implemented in partnership with the FAO, the OceanLitter Programme encompasses three projects: GloLitter Partnerships, RegLitter and PRO-SEAS.
The Programme supports developing countries, including Small Islands Developing States and Least Developed Countries, in identifying opportunities for the prevention and reduction of marine plastic litter from sea-based sources within the maritime transport and fisheries sectors.
The initiative brings its support through legal, policy and institutional reform. It promotes adequate port reception facilities to receive plastic waste, empowers women in finding solutions, spearheads marking systems to combat discarded fishing gear and establishes partnerships to share best practices across regions.
The OceanLitter Programme focuses on a number of areas identified in the adopted IMO 2025 Action Plan to Address Marine Plastic Litter from Ships and on complementary actions as identified by FAO, including supporting the provisions of the recently endorsed FAO Voluntary Guidelines on the Marking of Fishing Gear.
GloLitter Partnerships project
Established in 2020, the GloLitter Partnerships project was the first project of the OceanLitter Programme, initially funded by the Government of Norway.
GloLitter Partnerships aims to help the maritime and fisheries industries move towards a low-plastics future. The project assists the maritime transport and fisheries sectors in developing countries identify opportunities to prevent and reduce sea-based marine plastic litter through the re-use and recycling of plastics.
GloLitter Partnerships considers the availability and adequacy of port reception facilities and seeks to enhance awareness of the sea-based marine plastics issue within the shipping and fisheries sectors, including seafarers and fishers. As such the project encourages fishing gear to be marked so it can be traced back to its owners if discarded.
It develops guidance documents, training materials and toolkits to help enforce existing regulations and includes private sector participation through a global industry alliance (GIA).
To read more about GloLitter Partnerships Project.
RegLitter Project
The RegLitter Project, launched in November 2023, is funded by the Republic of Korea and focuses on action in the Asia region.
PRO-SEAS Project
IMO and FAO signed the Agreement on World Maritime Day 2025. The initiative will focus on Costa Rica, Jamaica, Kenya and Vanuatu.
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.
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 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.
Studies and reports
- How to monitor plastics in the oceans: Guidelines for the monitoring and assessment of plastic litter and microplastics in the ocean
Download free-of-charge from the GESAMP website here.
- What can be done with small recreational boats at the end of their lives: End-of-life management of fibre reinforced plastic vessels: alternatives to at sea disposal
Learn more about the existing solutions here.
- Hull scrapings and marine coatings as a source of microplastics: Hull scrapings and marine coatings as a source of microplastics
Download the study here.
- Microplastics in the Marine Environment: Sources, Fate and Effects of Microplastics in the Marine Environment (Part 2)
Download the report here.
Read more on: Recycling of Ships and the Hong Kong Convention