Plastic at sea

Plastic pollution is a hot topic today and for once the shipping industry is being seen less as the cause and perhaps more of a cure.

by Gillian Lovering

Shipping takes a lead in microplastic pollution battle

Plastic pollution is a hot topic today and for once the shipping industry is being seen less as the cause and perhaps more of a cure.

It has in fact been illegal for ships to dispose of any form of plastic at sea since 31 December 1988 when Annex V of the MARPOL convention came into effect. Annex V covers all forms of garbage but only plastic was singled out for a blanket ban.

At that time, the term microplastics was very likely not one that anyone involved in shipping either at sea or on shore had ever heard. In fact, in 1988, it was probably not a word that most people had heard or would understand. Microplastics and the threat that they pose to wildlife and the impact on the food chain first began to attract public attention a little over a decade ago.

Microplastics are defined as particles of plastic with a size less than 5mm. They can result from the breakdown of larger items of plastic in the environment or be nano particles often found in cosmetics, skin care products and industrial products.

While ships are supposed not to dispose of plastics of any sort, preventing discharge of some microplastics would seem to be unavoidable. Since they are used in some body scrubs, sun lotions, hair products, toothpastes and other seemingly innocuous items in daily use, they will inevitably end up in the grey water of all ships and from cruise ships in particular and find their way into the sea.

Shipping also contributes to other plastic waste at sea although not necessarily deliberately. It has to be accepted that there are ship operators and seafarers who will ignore the regulations against plastic disposal just as there are far too many people who litter and ignore rules generally. Unintentional disposal comes about by way of lost synthetic ropes and also the normal wear and tear of such ropes, from fishing gear, from cargo in containers lost overboard and also from paints and coatings used on hulls. In all it has been calculated that between them shipping and the marine leisure sectors account for only 2.9% of all the plastics in the ocean and fishing related activities some 10.8% 

Shipping steps up

Despite being a minor offender, the shipping industry through regulation and voluntary action is making an effort to reduce the problem. 

In 2018, the IMO adopted an Action Plan to address marine plastic litter from ships. The plan aims to enhance existing regulations and introduce new supporting measures to reduce marine plastic litter from ships. Through MEPC the IMO has agreed actions to be completed by 2025, which relate to all ships, including fishing vessels. The actions 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.

In the arena of ocean plastic clean up, there have been some significant notable initiatives by the shipping industry. This became most notable probably began in 2015 when at the Nor-Shipping exhibition, when Boyan Slat the Dutch founder and CEO of the environmentalist action group Ocean Cleanup was awarded the Young Entrepreneur Award.

An engineering student, Slat has developed systems for collecting plastic waste from the Great Pacific Garbage Patch and also from rivers which are the main source of ocean plastic waste. In its efforts to clean the world’s seas, Ocean Cleanup has been given a great deal of support by AP Møller -Maersk subsidiary Maersk Supply Service.

Since 2018, Maersk Supply Service has project managed and delivered offshore work for The Ocean Cleanup, including the tow and testing of the ocean systems. Despite some initial teething troubles with the system, Ocean Cleanup has refined its collection systems and is preparing to begin a new operation in 2022.

Maersk’s main contribution has been supplying the Supply Service vessel Maersk Tender for towing the garbage collection system. In May 2021, Maersk doubled its commitment with a second vessel Maersk Trader.

“Ocean Health is a priority for Maersk Supply Service. We are committed to reducing plastic waste in the oceans. Utilising two Maersk vessels and decades of experience is a great opportunity for us to further The Ocean Cleanup’s initiative and to help restore the oceans which we sail every day,” said Chief Strategy Officer Kristian Borum Jørgensen when announcing the provision of the second vessel.

In addition to the vessels and marine support from Maersk Supply Service, AP Møller-Maersk also provides logistics support to The Ocean Cleanup. They ensure global end-to-end transport of the equipment such as the collected ocean plastic and its river systems – The Interceptor.

The Ocean Cleanup campaign will probably have some success in removing larger items of plastic waste – which it recycles and markets products made from the waste to raise further funds – but the impact on microplastics will be less obvious.

The Shipping sector has however come up with another initiative that could help in recovering some of the microplastic circulating in the oceans. Last year, Japanese shipowner and operator Mitsui OSK Lines (MOL) in collaboration with compatriot ballast treatment system manufacture Miura to develop and test a water filtration device to capture the plastics. A prototype has been installed on a newbuild MOL wood chip carrier. 

The microplastics collection device is activated during the operation of the ballast water treatment system typically during the cargo handling operations in a port. Using a filter with a backwashing function for the ballast water treatment, the device efficiently collects microplastics trapped in the filter before the treated water is discharged overboard.

The majority of ballast treatment systems on the market have some form of filtration system and with systems already mandatory for new vessels and existing vessels being compelled to fit them by 2024 under a rollout programme, the potential for the shipping industry to contribute even more to removing microplastics would seem significant. It may take some time for the MOL/Miura project to be emulated by other ballast system makers especially as adaptations to systems may require a new type-approval application. However, the opportunity is there for shipping to show it is not such a dirty uncaring industry but has the ability to innovate and take action to aid the clean up of the oceans.

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