“Recycled plastic is good for our health and that of the planet”

The subject brought together more than 170 countries in South Korea, between November 25 and December 1. Participants were expected to sign a global treaty to end plastic pollution. An event supposed to be the culmination of a negotiation started in 2022. But the meeting did not make it possible to reach an agreement to finish the drafting of the first international treaty on plastic. The reason? The enormous financial stakes and the particular interests of the participating countries: each year, humanity produces more than 350 million tonnes of plastic waste.

However, plastics are a major source of pollution. 99% of them are produced from oil, gas or coal. They also have the characteristic of degrading into microparticles which remain for centuries in the environment… And in our bodies. A human being ingests, on average, 4.8 g of microplastics per week. 0.5% of our brain is made up of it. Is it dangerous for our health? Yes, certifies Nathalie Gontard, research director at INRAE*: “The studies are clear, the harmful effects obvious: inflammation, cancers… We know enough on this subject.”

Recycle them on a large scale could it reduce this pollution? Obviously not. Firstly, because it is impossible to transform some of them: many are composites, mixed with fiberglass, aluminum, or additives that are almost impossible to separate. Then, because plastic cannot be recycled infinitely. After two or three transformations, it becomes too fragile to be processed again. In addition, these multi-recycled objects continue to degrade into microparticles. They decompose even faster since they are already altered and therefore still pollute.

Plastics are thus destined to spread in nature or to be cremated. According to the UN, 9% is recycled worldwide. 79% end up in landfills or in nature. And 12% are cremated. So many new polluting substances and greenhouse gases. So, recycling is good, but changing models is better? “Yes, we must reduce our use of plastic,” concludes Nathalie Gontard.

* National Research Institute for Agriculture, Food and the Environment.

Sources: Inrae, WWF, American National Agency for Health and Biomedicine Research.