- 8.3 billion tons of plastic have been produced since 1950, half in the last fifteen years. And plastic production is expected to double again by 2040, according to Inserm.
- The size of the microplastic is between 5 millimeters and a few hundred nanometers, which is 70 times smaller than the thickness of a hair.
Microplastics, these plastic particles with a diameter of less than 5 millimeters, are a scourge for the environment, but also for the human being who, every week, would ingest about 5 grams, the equivalent of a credit, according to the WWF association. Widespread in the air, in nature and in the food chain, we find them nestled in the body: in the feces, in the placenta, in breast milk, in the lungs and even in the blood. What are the effects of this microplastic contamination on our health?
An “influence on the risk of developing diseases”
Currently, according to ANSES, the most widely found microplastics are polyethylene, polypropylene and polystyrene. All these plastics contain various additives (to give flexibility or strength for example) that “are potential chemical contaminants”but also “bacteria that can be biological contaminants”. However, although there is currently no real scientific consensus on the subject, “many elements suggest that these microparticles could influence the risk of some cancerous, inflammatory or immune diseases”says Mathilde Body-Malapel, a researcher at the National Institute of Health and Medical Research (Inserm), who evokes the harmful “cocktail effect” of these microparticles.
Brain, intestine: microplastics attack our organs
First observation, microplastics attack the brain, according to South Korean researchers. Upon entering the body, they accumulate in microglial cells, small immune cells of the central nervous system, and disrupt their functioning. These cells eventually die and the brain is no longer protected by an effective immune response. Other studies have revealed that microplastics could even, over time, participate in the proliferation of “superbugs” that are particularly resistant to antibiotics.
In light of the experiments carried out on mice, the contamination of food with microplastics could also harm the proper functioning of our intestine, altering the structure and immune function of the intestinal wall, and therefore the composition of the microbiota. The smallest plastic particles can even enter the bloodstream, the lymphatic system, and even reach the liver. This is one of the main dangers of microplastics: that they end up reaching the organs.
The cells themselves are destroyed by microplastics
Other work has shown that microplastics act as endocrine disruptors, which have the unfortunate reputation of disrupting hormonal functioning and causing many conditions, according to authorities: reduced sperm quality, altered reproductive organs, lowered age of the puberty …
In general, microplastics can affect the body’s own cells, a recent study reveals. On the bleak agenda: cell death, allergic reactions, tissue damage, oxidative stress, damage to the genetic information of cells … Many cellular disorders that “can be the trigger for many health problems”believe the researchers, who are calling for more research into the long-term health consequences of these microplastics.