The findings will inform the Environment Agency’s ongoing efforts to understand the impact and manage the risks from PFAS in surface waters. Many PFAS are frequently detected in rivers, estuaries and groundwater.

PFAS – also known as forever chemicals - are a large and diverse group of synthetic fluorinated chemicals, widely used in industrial applications and consumer items. They are extremely persistent in the environment, with some known to bioaccumulate and be harmful to health.

Environmental Quality Standards (EQSs) are statutory standards for chemicals in the water environment. They are threshold concentrations, used to assess and manage risks from chemicals to prevent harmful effects on ecosystems and/or human health through exposure via the environment. Only one PFAS currently has an EQS: perfluorooctane sulfonate (PFOS).

The project was commissioned to derive science-based threshold concentrations in surface water for more PFAS.

Thresholds were derived for the following PFAS:

The PFAS are frequently detected in English rivers and have relevant and reliable toxicology data.

The project used the method for derivation of EQSs, modified to focus only on the most sensitive endpoint. For the PFAS in this study, this is the protection of human health via the consumption of fish.

The toxicological data on which these equivalent water concentrations are based considered the combined effects of these four PFAS.

The values derived for PFOS do not replace the existing statutory EQS for PFOS.

Click here to download the research report Developing thresholds for managing PFAS in the water environment