Headlines recently reported on pollution in Perfluoroalkyl and polyfluoroalkyl substances (PFAS) Around several industrial sites in France, raising concern among local residents and environmental groups. Behind this barbaric name hide thousands of invisible, omnipresent and indestructible particles that are gradually polluting the entire planet.
Alas! For decades, we have been using and releasing thousands of synthetic chemicals with amazing properties into the environment. The other side of the coin? These once-believed miraculous substances inevitably accumulate in soil, water and living organisms, including humans.
PFAS (perfluoroalkyl and polyfluoroalkyl substances) are among these chemicals that are now serious health and environmental threats. They were invented in the 1930s due to their exceptional non-stick and water-repellent properties, and are now used for many everyday purposes.
But their amazing resistance to decomposition makes them stubborn pollutants that travel very long distances and accumulate in the food chain. They are associated with various toxic effects on health, and are now detected everywhere on the planet: from the poles to the tropics, from the peaks of the Alps to the depths of the great oceans.
In this article, we will explore the history and unique properties of this broad family of chemical compounds, their uses in our modern society, their already observed effects as well as the challenges they pose to our environment and collective health.
Definition and characteristics
PFAS (per- and polyfluoroalkyl substances) are a large family of more than 4,000 chemical compounds with very diverse properties. Their common feature is the presence of carbon-fluorine bonds, which is one of the strongest chemical bonds in organic chemistry, and this is what gives it unique properties:
- Non-sticky and waterproof.
- High temperature resistant.
- Soluble in both water and fats (amphiphilic).
These properties have made them useful in many industrial fields and everyday consumer products since the 1950s: textiles, food packaging, fire-fighting foams, non-stick coatings, cosmetics, phytosanitary products, etc.
PFAS are used in hundreds of types of everyday products:
- Stain-resistant clothing and carpets;
- Anti-greasy food packaging.
- Non-stick cookware (Teflon);
- fire fighting foams;
- Protective coatings for furniture, carpets and curtains;
- Sealing and insulation products;
- Paints and varnishes
- Cosmetics (nail polish, makeup removers, etc.).
They are also found in many industrial processes (rubber, plastics, metals, semiconductors, etc.).
In short, PFAS are all around us!
Persistence and accumulation in the environment
The other side of the coin of this family of miracle products is their extreme stability in the environment, hence their nickname “Eternal pollutants”.
Resistant to chemical and biological degradation, PFAS can persist for decades once released into nature. They then migrate easily into soil, groundwater and rivers.
It now exists everywhere on the planetincluding in remote areas such as the Arctic!
Through bioaccumulation along food chains, PFAS also enter living organisms. It has been discovered in many species of animals… and humans.
Health and environmental impacts
Although PFAS have been studied relatively recently, proven or suspected harmful effects have already been highlighted:
- Weak immune system.
- Increased cholesterol.
- Thyroid hormone disorder.
- Liver weakness.
- High blood pressure during pregnancy.
- Low fertility.
- Delayed growth in the womb.
- Kidney and testicular cancer.
- Weakness of the liver and immune system.
- Developmental abnormalities.
In the environment
- Bioaccumulation in fish and mammals;
- Ground and surface water pollution.
- Pollution of areas far from primary discharge sources.
Cocktail effects resulting from simultaneous exposure to multiple PFAS are also suspected.
Regulations are in their infancy
In the face of the growing threat posed by PFAS, regulatory measures are gradually being put in place at both international and national levels to restrict the most problematic PFAS:
- The Stockholm Convention on Persistent Organic Pollutants already regulates some PFAS such as PFOS.
- The European Union has set concentration limits in drinking water for 20 PFAS.
- The production of PFOA and PFOS is now banned in many countries.
- Other PFAS are subject to gradual restrictions (future bans on the production and use of PFHxS for example).
However, due to the large number of PFAS molecules that exist, global action demonstrates that new, complex, unregulated compounds are emerging as alternatives.
Humanity fair everywhere
Humans are exposed to PFAS mainly through:
- foodEspecially aquatic products that effectively bioaccumulate these substances;
- drinking water If it is contaminated.
- Indoor air and dust Impregnated with PFAS found in domestic products (carpets, sofas, kitchen utensils, etc.);
- Use some daily products (Cosmetics, textiles, food packaging, etc.).
Biomonitoring studies in the United States and Canada have detected PFAS in the blood of a very large majority of the population.
Contaminated soil around industrial sites in France
In France, investigation into environmental pollution caused by PFAS has just begun. Nearly 1,000 contaminated sites have already been identified, but many more yet to be explored sites are also likely to be explored.
There are two areas of particular concern :
About Lyon, the significant historical pollution around the Arkema and Daikin plants was highlighted. Record levels of PFAS have been measured in soil, groundwater, and even the Rhone River. PFAS have also been found in the blood of staff and residents. Some suspect the presence of cancerous clusters in these areas.
In Haute SavoieIt was also pointed out that the 3M plant in Rumilly was responsible for the contamination of soil and waterways. Here again, investigations are underway to determine the true extent of PFAS contamination and its health effects.
Actions remain timid by public authorities
In the face of the magnitude of this new environmental and health threatHowever, the reactions of the public authorities still seem very timid:
- Some sites are under strict surveillance (Lyon, Romilly);
- Announcing tighter controls on industrial discharges and drinking water quality;
- The government has just launched a “National PFAS Action Plan” in 2023.
But environmental associations and vulnerable populations are demanding that manufacturers take more ambitious and restrictive measures.
Issues and viewpoints
PFAS represent a major health and environmental challenge for years to come. Here are some associated problems:
- Improve detection and quantification in all media;
- Assess the toxicological risks of each PFAS individually or in combination;
- Effective techniques for remediation of contaminated sites;
- Replacing problematic PFAS in consumer products;
- Public awareness of avoidable sources of exposure;
- Health surveillance of exposed populations.
Despite their complexity, effective management of these ubiquitous pollutants is essential to reduce their impacts on ecosystems and human health.
(Marks for translation) Definition and characteristics
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