For decades, residents living near the Arkema and Daikin chemical factories near the southern city of Lyon believed they were safe. But after discovering alarmingly high levels of toxic forever chemicals (PFAS) in their blood, hundreds of alleged victims are filing complaints against the companies in what could become the largest lawsuit of its kind in Europe.
Per- and polyfluoroalkyl substances (PFAS) are found in everyday products such as cosmetics, pesticides, food packaging and non-stick coatings.
They're often referred to as "forever chemicals" because they can stay in the human bloodstream for years.
Studies have shown that exposure to these chemicals can lead to metabolic disorders, decreased fertility in women and developmental delays in children. They're also believed to increase the risk of some cancers.
In February, France passed a law banning their use in cosmetics, clothing and shoes, although not in cookware.
But the ban, which comes into effect in 2026, doesn't go far enough for people living in "chemical valley" – one of the biggest chemical and petrochemical parks in Europe, located along 17 kilometres of the Rhone river on the outskirts of Lyon.
As many as 220,000 people in the area could be affected by PFAS pollution.
Thierry Mounib lives in Pierre-Bénite, in the south of Lyon, opposite the Daikin and Arkema chemical factories.
"Over there is the testing centre, and behind are Daikin's workshops," he told RFI. "There's the nursery school. We took samples from there. It's a disaster."
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Mass legal action
Via his organisation Bien Vivre à Pierre-Bénite ("Living well in Pierre-Bénite"), Mounib is alerting people to the pollution, and the health problems that he believes are linked to PFAS.
"My wife has had breast cancer and Parkinson's disease. All around me, in every house, there's cancer," he said.
On 12 May, the American chemical giant 3M agreed to pay the state of New Jersey up to $450 million to settle claims it contaminated the state's drinking water with harmful “forever chemicals".
"Arkema and Daikin are refusing. They're not going to pay billions for the people of Pierre-Bénite," said Mounib.
He is one of around 400 plaintiffs that have signed up so far for a mass legal action, supported by the environmental groups Notre Affaire à Tous ("Our Shared Responsibility") and PFAS Contre Terre ("PFAS versus Earth")
It's a collective civil case, with the aim for each plaintiff to demand financial compensation from the two companies at the same time.
"It's the first civil lawsuit in France concerning PFAS contamination" says Louise Tschantz, a lawyer specialising in environmental law at Kaizen – the firm representing the plaintiffs. "And because of its scale it could become the largest case of its kind in Europe."
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Building a body of case law
Mounib filed his claim after a blood test showed his PFAS level was 22.6 µg/L of blood – 10 times higher than the average.
"When you look at the grid provided by the laboratory, when you’re above 20 you’ll have health problems. People who are not the closest to the plant, like us for example, we're 1.5 km away, think that they’ve escaped the problem. But we have serious doubts about the quality of the vegetables or eggs we are supplied with."
Victims could claim compensation not just for health issues but for emotional distress and property devaluation, amongst other things.
Sums could range from €1,000 to several million per person.
Tschantz hopes that the lawsuit will go beyond compensation and have a dissuasive effect on industrial companies.
"The idea is to create a body of case law that will have a real impact," she explained.
"We want this to cost them so much that next time in their business decision and in their steering committee they say to themselves, it’s not possible to react like that, we have to protect the environment and our health, otherwise the public will take legal action and that will cost us a lot."
This article was based on a piece in French by RFI's Juliette Pietraszewski
