Geneva (AFP)

The World Health Organization (WHO) believes that current levels of microplastics in drinking water are not yet a health hazard, but experts remain cautious for the future.

In a report released Thursday, WHO presents a synthesis of the latest knowledge on microplastics in tap water and bottled water and its effects on human health.

"The key message is to reassure drinking water users around the world: according to this assessment, we believe the risk is low," said the co-coordinator of the Water, Sanitation, Hygiene and Health Unit of the WHO, Bruce Gordon, at a press conference.

He said that the analysis of health risks related to microplastics focused on three aspects: the risk of ingestion, chemical risks and risks related to the presence of agglomerated bacteria (biofilm).

WHO insists that data on the presence of microplastics in drinking water are currently limited, with few reliable studies, and that these are difficult to compare, which makes the analysis more difficult. results.

WHO therefore calls on researchers to conduct a more in-depth evaluation using standard methods.

In a statement, the UN agency says that microplastics larger than 150 microns are not absorbed by the human body, and the absorption of smaller particles "should be limited".

It considers, however, that the absorption of very small microplastic particles, especially nanoparticles, "should be higher, even if the data on this subject are very limited".

"Microplastics in drinking water do not seem to pose health risks, at least at current levels, but we need to look deeper into the issue," said Maria Neira, director of the Public Health Department at WHO. , quoted in the press release.

The report warns of the dangers ahead: if plastic emissions in the environment continue at the current rate, microplastics could present widespread risks for aquatic ecosystems in a century, which should not be without consequences on human health.

"We need to stop the growth of plastic pollution around the world," said Neira.

Experts also stress the importance of wastewater treatment (fecal and chemical) which allows to remove more than 90% of microplastics present in these waters. Currently, a large part of the world's population does not yet benefit from adapted wastewater treatment systems, according to the WHO.

© 2019 AFP