“Eternal pollutants”: the growing fear of a toxic cocktail for health

“Eternal pollutants”: the growing fear of a toxic cocktail for health

PFAS, commonly called “eternal pollutants”, are already causing concern for several toxic effects on human health, including cancer, while knowledge on these substances remains to be completed.

Almost indestructible and present in a number of objects and products, per- and polyfluoroalkyl substances or PFAS accumulate over time in the air, soil, river water, food and, ultimately, in the body human.

What began as a so-called miracle, a technological breakthrough designed for practicality, quickly escalated into one of the most pressing public and environmental health problems of the modern world“, underlined in March 2023 the director of the United States Environmental Protection Agency, Michael Regan.

Some classified as carcinogenic

The International Agency for Research on Cancer (IARC), the cancer agency of the World Health Organization, in December 2023 classified two of the most prevalent PFAS as “carcinogenic to humans” et “possible carcinogen“.

In question: perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), the most studied until now in this large family and the two banned in Europe since 2019 and 2009, respectively.

For PFOA – previously classified as a “possible carcinogen” – the latest observations show “sufficient indications” of cancer among laboratory animals, “strong indications” of other risks such as immunosuppression, and cases ” “limited” of kidney tumors or testicular cancers in men, according to the WHO agency.

Although it presents the same potential risks, PFOS has so far only been associated with limited cases of cancer in animals and “insufficient indications” of cancer in humans.

However, the risk of cancer can vary greatly depending on different factors, such as the level of exposure to a substance. The IARC said it expected that workers producing PFOA or PFOS or using these substances directly in the manufacture of other products would be most exposed.

Several toxic effects

If “knowledge on the health risks associated with different PFAS is insufficient, or even absent”, “Harmful and toxic effects on human metabolism have been observed for several PFAS“, summarized the French General Inspectorate of the Environment and Sustainable Development (IGEDD) in spring 2023.

In the event of prolonged exposure, some of these synthetic chemical compounds can promote cancer, affect fertility and fetal development, or even increase the risk of obesity, according to various studies.

They are also suspected of interfering with the endocrine (thyroid) and immune systems“, also presented in Europe the National Agency for Food, Environmental and Occupational Health Safety (ANSES) in 2002, in the wake of the European Food Safety Authority (EFSA) in 2020.

But not all eternal pollutants, and the potential toxicity of each, are precisely known, which complicates health monitoring.

Public health concerns

In several countries, such as the United States, the Netherlands and Belgium, PFAS are attracting growing attention, among other things for a threat to health, and, in Europe, concern is particularly concentrated around “the valley of chemistry”, near Lyon (south-east).

Various legal and regulatory initiatives have been launched around the world against these “eternal pollutants” and their manufacturers, among other things for “endangering the lives of others”.

Contamination of drinking water but also of soil and air is often mentioned. At least 45% of tap water in the United States is contaminated with PFAS, according to a study by a government agency unveiled in July 2023.

In Europe, 17,000 sites are contaminated, including 2,100 at levels dangerous to health (more than 100 nanograms per liter), according to an unprecedented map from 17 media outlets, published in February 2023.

In Europe, several parliamentary works also raise awareness about health, including the proposed ban law from environmentalist MP Nicolas Thierry defended on Thursday.

Charged with a mission on PFAS by the executive, a majority deputy, Cyrille Isaac-Sibille (MoDem), pointed out at the beginning of February “a worrying public health subject” and called for “urgently stopping industrial discharges” containing PFAS, “without waiting for European restrictions”.