Scientists speak out against WHO draft guidelines for PFAS in drinking water

By Shannon Kelleher

The World Health Organization (WHO) is ignoring risks to human health posed by two toxic types of PFAS chemicals, and is failing to propose properly protective measures in draft guidelines for drinking water standards, a group of more than 100 scientists alleged in a letter issued this month.

The 116 scientists – all experts on per-and polyfluoroalkyl substances (PFAS) – said in the Nov. 10 letter that the WHO guidelines should either be “significantly revised” or be withdrawn. The group cited examples of areas where they said the WHO has omitted or obscured “strong evidence” of the links between adverse health problems and the PFAS compounds known as PFOS and PFOA. The WHO did not respond directly to criticisms expressed by the scientists in their letter.

“WHO has ignored the last 20 years of scientific research, ranging from observational human studies, animal studies, and mechanistic studies, and concluded that there’s not enough information,” said Linda Birnbaum, former director of the National Institute of Environmental Health Sciences and one of the signatories on the letter to WHO.

“I don’t understand how they could have come up with this [draft] using an independent group of scientists,” she added. “My impression is that people who consult largely for industry are the people who are involved in writing this. It’s very, very concerning.”

The WHO may release its final drinking water guidelines for PFOS and PFOA as early as December, and some fear the guidance could undermine regulations expected from the US Environmental Protection Agency (EPA) before the end of the year.

More