Floating plastic pollution of the oceans is now reaching “unprecedented levels”

In 2019, 171 trillion plastic particles, weighing about 2.3 million tonnes, were floating on the surface of the oceans, according to a new study published in the scientific journal Plos One. The figure is staggering. But the worst is yet to come: the amount of floating polymers could triple by 2040!

These results are better than we expected…“. In a few words, researcher Marcus Eriksen, from the 5 Gyres Institute in Los Angeles and lead author of the study, sums up the scientific community’s dismayed reaction to the new data.

The results are based on samples of floating plastics from the ocean surface taken at more than 11,000 stations around the world over 40 years, from 1979 to 2019. The researchers found no clear trend until 1990, then fluctuations between 1990 and 2005. But beyond that date, “we see a very rapid increase, due to rapid growth in production and a limited number of policies to control discharges“, Lisa Erdle, one of the authors, told AFP.

This acceleration in the growth of plastic on the ocean surface since 2005 is the most alarming phenomenon revealed by the study. A surprising “exponential growth“, admitted Marcus Eriksen, who recalls that between “350 and 425 million tonnes of new plastic have been manufactured each year since 2005“. This is due to increased packaging production, increased plastic consumption and waste generated by large fishing fleets. In the middle of the ocean, this pollution comes mainly from fishing gear and buoys, while clothing, car tyres and single-use plastics often pollute closer to the coast.

Less than 10% of the world’s plastic is recycled, adding to the pollution of the world’s waters. This situation can no longer be ignored, as it has disastrous consequences for marine ecosystems.

This massive presence of plastic waste on the surface of the water threatens animals, which become entangled in the larger pieces or ingest microplastics that then spread along the food chain to humans. According to UNESCO, every year about one million birds and more than 100,000 marine animals die as a result of ingesting or becoming entangled in plastic waste.

Today, studies are also looking into the toxicity of micro- and nanoplastics for humans.

“Nanoplastics have been found in human tissue, the bloodstream and even the placenta.”

Denis Ody responsible for the "Cetacean" programme within the WWF association

Raising awareness is needed

The extent of floating ocean pollution reminds us of the importance of developing waste collection solutions and implementing a curative approach, in conjunction with a global policy to reduce plastic pollution. These efforts can help to minimise their impact on the environment by recovering macro-plastics before they break down over time through light or mechanical degradation and are deposited on the seabed.
This is the strategy adopted by The SeaCleaners with the launch in March 2022 of the Mobula 8 clean-up vessel and the integrated MAPP (Mobula Against Plastic Pollution) programme in Bali, as well as the planned launch of the Manta in 2025.


The study’s authors warn that the amount of plastic in the aquatic environment could increase by about 2.6 times between 2016 and 2040 if stricter global policies are not implemented. “This observed acceleration in plastic densities in the world’s oceans, also reported on beaches around the world, requires urgent international policy intervention“, they write.

In this regard, it is encouraging to note that the UN Environment Assembly in Nairobi laid the groundwork for a “legally binding” text covering the entire life cycle of plastics, from production to recycling. This global treaty is expected to be finalised in 2024 and adopted in 2025, showing the responsibility of governments around the world facing this growing plastic pollution. The SeaCleaners, a member of the NGO Task Force working on the development of this treaty, is involved in the negotiation round. The 2nd round will take place in Paris from 29 May to 1 June.

*  Marcus Eriksen dans une étude publiée dans la revue scientifique Plos One 


  •  Eriksen M, Cowger W, Erdle LM, Coffin S, Villarrubia-Gómez P, Moore CJ, et al. (2023) A growing plastic smog, now estimated to be over 170 trillion plastic particles afloat in the world’s oceans—Urgent solutions required. PLoS ONE 18(3): e0281596. https://doi.org/10.1371/journal.pone.0281596