Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what steps his Department has taken to prevent the leaching of per- and polyfluoroalkyl substances into supplies of drinking water.

There are already statutory duties on water companies and local authorities to carry out risk assessments and sample drinking water supplies for anything which would constitute a potential danger to human health. This includes per- and polyfluoroalkyl substances (PFAS). The Drinking Water Inspectorate has a guideline value on individual types of PFAS of 100 nanograms per litre. It was set in 2021 based on an assessment of existing scientific knowledge and agreed with the UK Health Security Agency (UKHSA) to be a robust level with an appropriate margin to ensure our drinking water is safe to drink. There is no evidence of PFAS concentrations above this value in drinking water supplies.

Nevertheless, work is continuing with other government departments, regulators and the devolved administrations to assess levels of PFAS occurring in the environment, their sources and potential risks to safeguard current high drinking water quality and ensure our regulations remain fit for purpose.