A strong alliance to end "Marine Litter"

The pollution caused by debris and trash that ends up in oceans, seas, or other large bodies of water ("marine litter") is a challenge, experts around the world are working hard to address. It is undeniably a global concern we must tackle. The plastics industry takes an active role in getting to the bottom of the problem and creating solutions. It pays special attention to "microplastics".

The German-Russian collaborative Kuril Kamchatka Biodiversity Studies (KuramBio) [1] conducted several deep-sea expeditions to the Northwest Pacific between 2010 and 2016. Participating scientists of the Senckenberg Research Institute and Natural History Museum Frankfurt and the Department of Microbial Ecology of the Biological Institute Helgoland collected sediment samples in the Kuril Kamchatka Trench, which extends for about 2,250 km and boasts a maximum depth of 10,542 meters. The samples were taken at different depths and subsequently tested in the laboratory for the presence of plastic debris. The results: Hardly any sample was free of microplastics particles, including fragments that are by definition smaller than 5 millimeters in diameter. According to the researchers, the proportion of microplastics in the samples varied between 14 and 209 particles per 1000 grams of dry sediment. The number of particles increased with increasing depth at which the samples were taken. The scientists concluded that oceanic trenches act as veritable traps for microplastics. [2]

The findings of the KuramBio studies can prove to be a valuable clue to colleagues at the Geomar Helmholtz Centre for Ocean Research in Kiel, Germany. The scientists aim to find out where all plastic waste that is released in the global oceans ends up. Prior research had shown that a portion of this waste simply vanishes into thin air. According to a statement by Geomar, the percentage of plastics in the surface layer of the oceans is actually lower than expected. This observation specifically pertains to microplastics. While the observed accumulation of microplastics in the surface ocean is lower than expected, high levels of these microplastics are recorded in the deep seafloor.

But how do microplastics get to the seafloor? After all, plastics are a type of polymer that is lighter than water and should thus float on its surface! Geomar has made it its mission to answer this and other questions. Models were used to simulate the movement of the microplastic particles in the oceans and to find out which biological processes are responsible for the sinking of particles into the deep sea. The results of the study models shed some light on the situation.

The Geomar researchers lay the responsibility for microplastic sinking into deeper sea levels squarely on plankton, which live near the surface. Plankton are the diverse collection of organisms found in water that are unable to propel themselves against a current and drift along with the tide. Plankton form the bottom level of the ocean’s food chain and enter the main food chain when they are eaten by microscopic animals (zooplankton). These organisms serve as an intermediary species that are food for the larger invertebrate predators and fish who, in turn, are eaten by larger fish. Humans are at the top of the food chain.

So how are microplastics transported to the seafloor? The answer: There is a high probability that feces, dead cells, or other organic structures bind with the microplastic particles, serving as a concentration or focal point. This prompts a loss of buoyancy, causing the microplastic to sink into the depth – just like snowflakes. Once there, bacteria break down the organic detritus and release the polymers, which either rise back to the surface or float further into the depths. According to Geomar, only one out of two microplastic particles will be transported into the deeper levels, and in some regions only one of three will sink. The researchers explain that despite being an "inefficient removal mechanism", the process is still effective in removing enough plastic from the surface ocean. The “marine snow” thus has a great impact on the shape of the global microplastic distribution. [4]

The "marine litter" phenomenon and the search for microplastic particles in the ocean make one thing abundantly clear: we would be better off if we didn’t have to deal with the subject matter in the first place and if the oceans and other ecosystems were free of any anthropogenic debris. Let's look at the causes of "marine litter pollution":

The lion's share of plastic waste that ends up in the oceans comes from mismanaged waste. Carelessly discarded packaging, bottles, closures, cigarette butts and other similar items only add to the problem. In the past, plastic granules and pellets used to manufacture different plastic end products have likewise been found on the coastlines of rivers and oceans. In other words, this is a multifactorial, systemic problem that requires us to pull out all the stops to find a solution. The message is clear: If consumers are responsible for proper waste disposal, the plastics industry, for its part, is also tasked with the careful management of raw materials and containment of plastic pellets.

This means we know some of the challenges and possible solutions. The growing threat is being addressed: European plastics manufacturers are committed to preventing plastic pellet loss into the environment. To this end, Plastics Europe (https://www.plasticseurope.org/), the Association of Plastics Manufacturers in Europe, has launched the Operation Clean Sweep (OCS) programme in 2013 [5]. It is aimed at all key actors along the entire plastics industry value chain, including plastic manufacturers, processors and distributors, logistics and recycling companies. According to Plastics Europe, more than 500 European companies have so far signed their pledge to the OCS programme, thus covering over 98% of the total European plastics production [6].

What are some other actions that address the growing problem of marine litter in our oceans? Celebrated each year on June 8 since 2009, "World Oceans Day" is an annual opportunity to raise global awareness of this issue. Many countries have celebrated this special day since June 8, 1992, following the "United Nations Conference on Environment and Development", held in Rio de Janeiro that same year. It is often also referred to as the "Earth Summit" or the "Rio Conference" [7]. It takes many stakeholders to recognize and honor the importance of our environment and protect our oceans and preserve our future. The plastics industry is committed to doing its part in this global endeavor. Here are some examples:

• Nearly 70 organizations and industry associations in over 40 countries have signed "The Declaration of the Global Plastics Associations for Solutions on Marine Litter" (https://www.marinelittersolutions.com/about-us/joint-declaration/). The plastics industry embraces its responsibility and implemented more than 350 projects to contribute to solutions that prevent marine debris. [8]
• Leading plastic makers from Asia, the Middle East, North and South America, and Europe have joined forces to create the "World Plastics Council" [9] to fight global pollution caused by discarded plastic through groundbreaking innovation.
• More than 35 international groups and companies have come together under the umbrella of the non-profit organization (NGO) "Alliance to End Plastic Waste" to work on new ways and efficient solutions for minimizing plastic waste in the environment. The members of the Alliance use their expertise, material, and technological know-how, as well as considerable financial resources in pursuit of this ambitious goal. The Alliance has its European headquarters in London, where all threads come together, and the decisions of the members are translated into strategies and procedures. The Alliance pursues its goals in close cooperation with strategic partners such as the World Economic Council for Sustainable Development (WECSD) and the United Nations Environment Programme (UNEP). [9]

The focus on entrepreneurial and institutionalized interests makes the seriousness of the situation clear; long-term and lasting solutions require commitment, energy, and a great deal of monetary support. The "Alliance to End Plastic Waste" has paid particular attention to combating the pollution of the world’s oceans with plastic waste, much of which is washed into the oceans via tributaries, which brings us back to the beginning of this article. One of the Alliance's objectives is to interrupt this flow of waste via rivers and supports corresponding projects around the world:

• "Renew Ganges": This project is dedicated to freeing the 2,600 km long Ganges, a river that is highly polluted with wastewater and other emissions, from pollutants. The Ganges flows through the vast plain south of the Himalayas, one of the most densely populated regions on the planet.
• In Indonesia, the world's largest island state and fourth most populous country with 264 million inhabitants, the Alliance is supporting the development of an infrastructure for waste collection and recycling. The Alliance focuses on projects that have a sustainable impact, emphasize damage limitation, a change in thought patterns and a resulting paradigm shift.

Plastics are produced to fulfil important tasks and functions. However, used plastics do not belong in the environment, but back in the recycling loop – referring to a "circular economy", a top priority issue for the plastics industry. Mastering this challenge requires a commitment on the part of society as a whole. Everyone is called upon to make his or her contribution to the preservation of an intact and livable environment. What's your idea?

[1] https://www.senckenberg.de/de/institute/senckenberg-gesellschaft-fuer-naturforschung-frankfurt-main/abt-marine-zoologie/sekt-crustaceen/crustaceen-forschung/kuril-kamchatka-biodiversity-studies-kurambio/

[2] Abel et al., Systematic identification of microplastics in abyssal and hadal sediments of the Kuril Kamchatka trench, Environmental Pollution (2020) 116095, ISSN 0269-7491, https://doi.org/10.1016/j.envpol.2020.116095

[3] Kumar et al., Analysis of microplastics of a broad size range in commercially important mussels by combining FTIR and Raman spectroscopy approaches. Environmental Pollution (2020).  https://dx.doi.org/10.1016/j.envpol.2020.116147

[4] Kvale et al., The global biological microplastic particle sink, Scientific Reports (2020). https://doi.org/10.1038/s41598-020-72898-4

[5] Operation Clean Sweep, http://www.opcleansweep.eu/impacts/

[6] PlasticsEurope on Operation Clean Sweep, https://www.plasticseurope.org/de/newsroom/press-releases/pressemitteilungen-2019/neuer-report-zu-operation-clean-sweep-veroeffentlicht

[7] Wikipedia, The United Nations Conference on Environment and Development (UNCED), https://de.wikipedia.org/wiki/Konferenz_der_Vereinten_Nationen_%C3%BCber_Umwelt_und_Entwicklung

[8] Marine Litter Solutions, Solutions for Our Ocean,  https://www.marinelittersolutions.com/

[9] World Plastics Council, https://www.worldplasticscouncil.org

[10] Alliance to End Plastic Waste, https://www.endplasticwaste.org