Oceans have suffered, since 2005, an “unprecedented” tidal wave of plastics, according to a report that urges closing the negotiation of an international agreement to tackle the problem.
Plastic pollution is a persistent problem across the planet, at all levels. Marine fauna swallow or remain trapped in the bags, waste litters the beaches even in the most remote natural spaces, and microplastics return to humans through the food chain.
The report, published on the PLOS One site, estimates that some 170 trillion plastic fragments float in the seas, mostly microplastics. A large part of those fragments were discarded in the last 18 years. “Plastic pollution has reached unprecedented levels”, the authors warn.
The figure is significantly higher than previous estimates, and the study highlights that landfilling is expected to accelerate over the next few decades if current rates are maintained. The researchers collected samples at more than 11,000 monitoring stations around the world, and data spanning 40 years, between 1979 and 2019.
Until 1990, there was no clear trend in the concentration of those plastics, and then until 2005, the trends fluctuated. From that year the levels skyrocketed. “We are seeing a rapid increase since 2005 because there is a rapid increase in production, while policies to control ocean plastic dumping are limited”, explained one of the authors, Lisa Erdle.
The causes of plastic pollution in the ocean are numerous. Fishing nets or buoys usually appear in the middle of the sea, while bags, clothing or car tires are present on the coasts. All that debris ends up turning into microplastics, like “confetti on the surface of the ocean”, in the words of Lisa Erdle.
The G20 countries will double their use of plastics by 2050, to 451 million tons according to the report, produced jointly by Economist Impact and The Nippon Foundation. In 1950, only 2 million tons of plastics were produced worldwide.
Recycling, even in the most advanced countries, has had little impact so far. Without proper management, plastics deposited in landfills can end up in the sea. “More recycling is needed, we are witnessing a real spill of toxic products and packaging”, explained Erdle.
More urgent actions are needed!
Between 1990 and 2005, there were international efforts to partially alleviate the problem, such as the 1988 MARPOL treaty, signed by 154 countries to prohibit the dumping of plastics from ships. But the increase in production has surpassed those legal frameworks, warns the study, which is now advocating for a new global treaty.
In December 2022, more than 160 countries gathered in Uruguay, under the aegis of the UN, began negotiations for this global agreement against marine plastic pollution, but the second round must now be held in France. The main points of the agreement are a ban on the use of single-use plastics, a system of fines for pollutants and taxes on producers.
The total weight of plastic pollution detected to date is around 2.3 million tons, according to the PLOS study. The text analyzed data from the Atlantic, Pacific and Indian oceans, as well as the Mediterranean Sea.