The authors of the study said their findings underscore the urgent need to prevent pollution from these substances before they enter the environment.

Despite their cost, cleanup efforts remove less than two percent of the current pollution from perfluoroalkyl or polyfluoroalkyl substances, known by their acronym PFAS, according to the paper.

The study, published in the journal Environmental Science: Processes & Impacts, was led by scientists in collaboration with journalists as part of the Forever Pollution Project, coordinated by the French newspaper Le Monde.

Researchers based their analysis on more than 12,000 suspected contaminated sites across Europe, along with databases covering drinking water, wastewater, sewage sludge spread on farmland and landfills.

"Full remediation of PFAS-contaminated environments is financially and logistically unachievable," said Eurydice Bersi of Reporters United, an Athens-based network of investigative journalists.

"The only effective strategy is to stop the pollution at its source, such as preventing use and remediating at the point of emissions," Bersi said.

Using those datasets and an assessment of currently available treatment technologies, the team estimated that removing so-called "emerging" PFAS compounds, including trifluoroacetic acid (TFA), would cost roughly 100 billion euros ($114 billion) a year.

That price tag is about 50 times higher than the estimated cost of dealing with older PFAS chemicals such as PFOA and PFOS, which are now heavily regulated across Europe.

TFA has become one of the most widespread PFAS contaminants in the environment and is among the most difficult to remove.

PFAS are a large class of synthetic chemicals used in everything from nonstick cookware and clothing to industrial manufacturing, which break down extremely slowly.

"We are making so much PFAS, and they are so persistent and mobile that remediation alone cannot keep pace with ongoing emissions," said the study's lead author, Alison Ling of the University of St Thomas in Minnesota.

"Clean-ups make sense where they meaningfully reduce exposures and health risks, but even unprecedented spending on remediation could not significantly reduce the amount of PFAS already in the environment," Ling said.