Plastics and oceans: the devastating confrontation

Plastic waste is a growing problem: plastics production is set to double over the next decade and, without planning for effective waste management, the social, economic and environmental impact is also expected to increase. We are now faced with the pollution of the oceans by the plastic that has invaded our lives. However, in recent years, many initiatives have been taken at all levels to put in place strategies and means to manage this complex problem. 

 

Aoday, we are inundated with plastic waste due to our careless approach to the use and, even more so, the lack of planning for the life after use of this sustainable material, which has come with a significant social, economic and ecological impact and cost. According to the report of the Institut Veolia - Facts Reports magazine devoted to Plastics, 5,250 billion plastic particles float on the surface of the world's seas and oceans, the equivalent of 268,940 tonnes of waste..

Over the next ten to fifteen years, global plastic production is expected to double, according to the latest WWF report released on 5 March 2019. This means that the systems for manufacturing, distributing, consuming and trading in plastics must change.

Most marine litter consists of materials that degrade slowly or not at all (most of this litter drifts into the sea before it deteriorates, a process that can take between 100 and 1,000 years), so that a continuous input of large quantities of these materials causes them to gradually accumulate in the marine and coastal environment.

 

This negative trend has been confirmed by several studies in different regions, clearly indicating that the situation regarding marine litter continues to deteriorate. As a result, marine litter is not only an environmental problem but also a health, economic and aesthetic problem.

 

Nine billion tonnes of plastic have accumulated since 1950; only 9 % of plastic is recycled; 150 million tonnes of plastic waste are in the oceans; 100 % of the Mediterranean Sea is polluted by plastics, according to the'article published in the Institut Véolia magazine under the title "L'indispensable réinvention des plastiques" (The indispensable reinvention of plastics). According to Ifremer experts, 700 tonnes of waste are dumped every day into the Mediterranean Sea, which is one of the regions most affected by marine pollution, particularly plastic pollution. This is also the opinion of the Bouches-du-Rhône MPFrançois-Michel Lambert, who believes that "50% of the world's micro-plastics are now in the Mediterranean". 

 

Our colleague, the magazine The Conversation explains this situation because of the semi-enclosed nature of the Mediterranean Sea, which is more exposed than the oceans: the rate of renewal of its waters is 90 years, while the persistence of plastics is over 100 years.

Between 1 000 and 3 000 tonnes of plastics are currently floating on the surface (fragments of bottles, bags, packaging, fishing line...), mostly from the accumulation areas of coastal cities, areas with high tourist activity and open dumps. Most of the Mediterranean pollution comes from the 250 billion fragments of microplastics found there, according to estimates by theMED Expedition.

A problem exacerbated by other factors: densely populated coastlines, highly developed tourism, the passage of 30 % of the world's maritime traffic, and additional inputs of waste through rivers and highly urbanized areas.

According to the WWF Report 2018Plastic accounts for 95 % of waste on the high seas, on the seabed and on the beaches of the Mediterranean. This has led some experts to describe it as the sixth largest marine litter accumulation area in the world, after the five ocean gyres. 

 

 

In 2014, the Tara foundation conducted a nine-month expedition in the Mediterranean basin to specifically study microplastics and understand their impact on this ecosystem. It enabled 2,000 samples to be taken from some 350 stations, near the coasts, near cities, river mouths and in ports. Data representing 75,000 plastic particles are currently being analysed.

The expedition has already led to a clear observation: whether near the coast or further offshore, the Mediterranean is polluted to 100 % by plastics. Even more alarming, the concentration of microplastics is sometimes as high as that found in the "7^e continent of plastic" - which is three times the size of France, in the Pacific. Their number is also close to the order of magnitude of the plankton at the base of the food chain.

 

The United Nations Environment Programme (UNEP) defines marine litter as "any solid material that is persistent, manufactured or processed, discharged, disposed of or abandoned in the marine and coastal environment". It is material lost or discarded by people in the seas, rivers, beaches, or brought in by rainwater, sewage or wind, or by objects such as fishing nets and lost cargo.

It is estimated that more than 150 million tonnes of plastics have accumulated in the world's oceans and that :

- 50% consumer plastics are single-use;

- 10% of all human waste is plastic;

- 500 billion plastic bags are used every year;

- 1 million plastic bottles are bought every minute;

- 13 million tons of plastic leaks into the ocean every year;

- 100,000 marine animals are killed by plastic waste every year.

 

Marine litter can be transported over long distances by ocean currents and winds, and therefore ends up in all seas and in isolated areas, such as on islands in the middle of the oceans and in the polar regions.

 

As described in the UNEP report on 'global lessons', microplastics are generally defined as small particles or fragments of plastic measuring less than 5 mm in diameter. Some microplastics are deliberately manufactured for industrial and domestic use. Others are the result of the alteration and fragmentation of larger plastic objects (synthetic textile fragments, plastic particles used in cosmetics, industrial cleaning products, etc.), a process that is enhanced by exposure to UV radiation but becomes extremely slow once the plastic sinks below the surface. Even plastics marked as "biodegradable" do not degrade quickly in the ocean. Nano-sized plastics are probably as common as micrometre or micrometre-sized plastics, but their dangers are less well understood and could be more complex. The main sources of macroplastic losses are from poorly managed municipal solid waste (i.e., open landfill and insufficient landfilling), accounting for about half of the macroplastics dispersed in the environment.

 

The main sources of macroplastics losses come from poorly managed municipal solid waste (i.e. open landfills and inadequate disposal), accounting for about half of the macroplastics lost to the environment, mainly in Africa, Latin America, the Caribbean and the Middle East, all of which consume large amounts of plastics and produce a large proportion of poorly managed household waste. The quantities and types (size, shape, density, chemical composition) of the materials, as well as the points of entry into the ocean, will largely determine the subsequent distribution and impact.

 

The losses of microplastics, on the other hand, are mainly due to a large population and per capita consumption of plastics. The most contributing regions are North America, China, Asia (excluding Japan, India and China) and Western Europe.

 

Marine litter threatens marine and coastal biological diversity in productive coastal areas, causing damage and death to wildlife. Entanglement in fishing nets and ingestion are the main types of direct damage to wildlife caused by marine litter, such as barnacles and worms, which devour pieces of macroplastic. Other threats to wildlife and the environment include seabed cover and habitat disturbance related to mechanical beach cleaning.

 

Marine litter is also increasingly seen as a source of accumulation of toxic substances or ecosystem disruption in the marine environment due to the transfer of invasive species between seas, such as algal blooms, and harmful pathogens. For the GESAMP report, however, it is not clear whether at the currently observed rate of increase in microplastics, this will be significant at the population level.

 

Each year, the presence of marine litter also causes damage that results in health risks and loss of life, property and livelihoods, as well as high economic costs. In addition, marine litter spoils and destroys the beauty of the sea and the coastal zone.

 

Plastic waste, in particular of medical and sanitary origin, ingested by marine organisms (fish, crustaceans, ...) may constitute a health risk and could potentially cause serious damage. Generally speaking, it is believed that only the smallest particles (1.5 micrometers or less) of these plastics can enter the capillary vessels of organs and the rest will be excreted. Some of these microplastics are suspected of then being able to interact with the immune system, cause oxidative stress or cause DNA damage.

 

Nevertheless, there are many gaps in knowledge, such as toxicological data on commonly ingested microplastics, their potential impact resulting from the cooking or high-temperature processing of fish foods, as well as on the specific routes of absorption, distribution and translocation of these microplastic particles in human tissues and organs.

 

 

According to the recent report of the Food and Agriculture Organization of the United Nations (FAO) on the fate of plastics in the human body and their potential adverse health effects, much remains to be established and, on the basis of the scientific evidence currently available, microplastics do not appear to pose a significant threat to food safety, as the health benefits associated with the consumption of fishery products outweigh the potential risks.

 

Among the major reasons for the marine litter problem, which appears to be worsening worldwide, are the waste practices of the shipping industry, as well as the lack of land-based infrastructure to receive the waste, coupled with the lack of awareness of key stakeholders and the general public, particularly in developing countries. The UNEP analytical report on marine litter highlights in this context that among the main contributions to the problem were gaps in the implementation and enforcement of existing international and regional environmental agreements, as well as national regulations and standards.

 

The most urgent short-term solution to reducing plastic inputs, particularly in developing economies, is to improve waste collection and management. Resolution 3/7 on marine litter and microplastics, adopted at the 3rd session of the United Nations Environment Assembly, thus calls on all countries and other stakeholders to use plastics responsibly, while striving to reduce the unnecessary use of plastics and to promote the research and application of environmentally sound alternatives.

The problem is that marine litter is not always specifically mentioned in global or regional conventions, agreements or action plans. Long-term solutions include improved governance at all levels, as well as behavioural and system changes, such as a more circular economy and more sustainable production and consumption patterns.

 

At the same time, a wide range of instruments related to marine litter already exists and actions are underway at global and regional levels. Education, information and training are therefore among the essential components of all efforts to be implemented to promote a more rational reflection on waste in society in general. On a practical level, the plastic bag bans in force in more than 100 countries prove how powerful direct government action on plastics can be.

READ UP'. : Plastics recycling: what are governments doing?

In order to avoid marine litter originating more specifically from maritime transport, offshore platforms and fishing vessels, efforts should be made to reduce the generation of waste and its spread, which should be stored on board and landed in an appropriate reception facility. All fishing equipment and materials, in particular drift nets, should be marked so that they can be found if lost at sea. No fishing gear should ever be deliberately discarded at sea but taken ashore for proper disposal.

 

Degradable plastics are also being developed, which could help to reduce the amount of persistent plastics in the environment, but could also send the wrong signal to people and would be quite contradictory to the many attempts to change their consumer behaviour. And if contamination of the environment by certain so-called "compatible" wastes were to be considered acceptable, it would be very difficult to draw a dividing line and achieve a consistent change in attitude and behaviour.

 

At the European level, the establishment of monitoring programmes is an important step in the implementation of the Marine Strategy Framework Directive 2008 (MSFD - 2008/56 / EC). This consisted in the development of a "Guide on the monitoring of marine litter in European seas". Pollution of the seas by plastics and microplastics has also become one of the three main areas of the European strategy for plastics in a circular economy adopted by the European Commission in January 2018.

READ IN UP' : To clean seas and oceans, swim!

Developing countries face challenges related to capacity building, resource mobilization and the lack of alternatives to replace certain types of plastics. Small island developing States are particularly vulnerable to the problem of plastic and microplastic waste at sea and face significant challenges in managing such waste and plastic pollution. Those States therefore require international support to address the problem, as well as awareness-raising programmes on marine litter and microplastics, especially for the most vulnerable populations.

Source : Greenfacts, February 15, 2019 - References

 

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Header photo : ©WWF France