What are the "forever chemicals" found in UK drinking water?

Pfas, or per- and polyfluoroalkyl substances, are a group of synthetic chemicals that have been detected in high levels in untreated water sources across England and Wales.

What is the estimated cost to clean up the Pfas pollution in the UK and Europe?

Experts warn that the total cost of cleaning up Pfas pollution across the UK and Europe could reach an astronomical £1.6 trillion over the next 20 years.

Home / Environment / Regulator Flags Carcinogenic "Forever Chemicals" in UK Drinking Water Supplies

Regulator Flags Carcinogenic "Forever Chemicals" in UK Drinking Water Supplies

Q: How many people are affected by the Pfas contamination in UK drinking water?

The analysis found that the Pfas issues were flagged in water treatment works, reservoirs, and supply systems serving over 6 million people, though the true number could be much higher.

3 Nov

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Summary

Drinking water watchdog orders action on Pfas contamination in untreated water
Hundreds of water treatment sites serving over 6 million people affected
Cleanup costs estimated at £1.6 trillion across UK and Europe over 20 years

Regulator Flags Carcinogenic "Forever Chemicals" in UK Drinking Water Supplies

As of November 3rd, 2025, the UK's drinking water watchdog has raised serious concerns about the presence of harmful "forever chemicals" in untreated water sources across England and Wales. The Drinking Water Inspectorate (DWI) has ordered water companies to take action after detecting high levels of per- and polyfluoroalkyl substances (Pfas) that "could constitute a potential danger to human health".

Pfas are a group of synthetic chemicals used for their waterproof and grease-resistant properties. These compounds persist in the environment, can accumulate in the body, and have been linked to cancer, hormone disruption, and fertility issues. An analysis of DWI data found that the regulator had flagged Pfas contamination in hundreds of water treatment works, reservoirs, and supply systems serving over 6 million people.