Plastic contamination of the ocean is irreversible, warns WWF

Posted on 8 February 2022

A new WWF-commissioned review of over 2,590 studies provides the most comprehensive analysis to-date of the alarming impact and scale of plastic pollution on ocean species and ecosystems.

Current projected growth in plastic pollution will cause significant ecological risks, with certain pollution hotspots like the Mediterranean, the East China and Yellow Seas, and the Arctic sea ice already exceeding ecologically dangerous threshold of microplastic concentrations.

The review warns that by the end of the century, marine areas more than two and a half times the size of Greenland could exceed ecologically dangerous thresholds of microplastic concentration, as the amount of marine microplastic could increase 50-fold by then. This is based on projections that plastic production is expected to more than double by 2040 resulting in plastic debris in the ocean quadrupling by 2050.

Commissioned by WWF and conducted by the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, the report “Impacts of plastic pollution in the ocean on marine species, biodiversity and ecosystems'' notes that microplastic concentrations above a threshold level of 1.21 x 105 items per cubic metre have now been estimated in several regions around the world. This threshold, above which significant ecological risks are likely to occur, has already been exceeded in certain pollution hotspots like the Mediterranean, the East China and Yellow Seas and the Arctic sea ice.

In the worst case scenarios, exceeding ecologically dangerous thresholds of microplastic pollution could lead to adverse effects on species and ecosystems including reduced populations.

"All evidence suggests that plastic contamination of the ocean is irreversible. Once distributed in the ocean, plastic waste is almost impossible to retrieve. It steadily degrades and so the concentration of micro- and nanoplastics will continue to increase for decades. Targeting the causes of plastic pollution is far more effective than cleaning up afterwards. If governments, industry and society act in unison now, they can still limit the plastic crisis," said Heike Vesper, Director Marine Programme, WWF Germany.

Given the pervasiveness of plastic pollution, nearly every species has likely now encountered plastic. Negative impacts from plastic pollution are already detectable in most species groups while the productivity of several of the world’s most important marine ecosystems, like coral reefs and mangroves, are under significant risk.

Where other threats such as overfishing, global warming, eutrophication, or shipping overlap with plastic pollution hotspots, the negative impacts are amplified. For already threatened species, some of which live in such hotspots, such as monk seals or sperm whales in the Mediterranean, plastic pollution is an additional stress factor pushing these populations towards extinction.

“Research acts like a flashlight with which we cast rays of light into the darkness of the oceans. Only a fraction of the effects have been recorded and researched, but the documented effects caused by plastic are concerning and must be understood as a warning signal for a much larger scale, especially with the current and projected growth in plastic production,” said Dr. Melanie Bergmann, Marine Biologist, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research.

The durable nature of plastic also means that the uptake of microplastic, and nanoplastic, in the marine food chain will only continue to accumulate and reach dangerous levels, if we do not cut our production and use of plastic now.

This pervasive and ever-growing threat to ocean life can only be tackled with an efficient global and systemic solution, which countries can establish by adopting a global treaty at the UN Environment Assembly 5.2 in February.

Pressure is mounting on the international community for a legally binding treaty. More than 2 million people around the world have signed a WWF petition, while over 100 global companies, more than 700 civil society organisations and 156 countries, making up more than ¾ of UN member states, have also backed calls for a treaty.“Without a doubt, unchecked plastic pollution will become a contributing factor to the ongoing sixth mass extinction leading to widespread ecosystem collapse and transgression of safe planetary boundaries. We know how to stop plastic pollution and we know the cost of inaction comes at the expense of our ocean ecosystems – there is no excuse for delaying a global treaty on plastic pollution. The way out of our plastic crisis is for countries to agree to a globally binding treaty that addresses all stages of plastic’s lifecycle and that puts us on a pathway to ending marine plastic pollution by 2030,” said Ghislaine Llewellyn, Deputy Oceans Lead, WWF.

More on plastic pollution in the Mediterranean.

Plastic ocean pollution. Whale Shark filter feeds in polluted ocean, ingesting plastic.