Skip to main content
hpa logo
Topics A-Z:
Search the site:


In England and Wales water companies supply water that is wholesome and safe to drink. Occasionally, chemicals may be present in water, from agricultural or industrial activities, or following accidental release.

The Government has set water quality regulations, which must be met by the water companies, in order to safeguard the high quality of water. The Drinking Water Inspectorate (DWI) ensures that such standards are met and that the water is safe to drink.

CHaPD, through the General Toxicology Unit, is a central source of advice to DWI, Department of Health (DH), Department of the Environment, Food and Rural Affairs (Defra) and Environment agency (EA) on the health risks of chemicals in drinking water and provides expert toxicological advice to such governmental bodies, regulators and the public.

CHaPD also provides toxicity advice to the DWI in the context of the approval of various products used in the treatment or supply of public drinking water.

The HPA's Health Protection Units and Local and Regional Services also respond to enquiries from the public on the health risks of chemicals in drinking water, seeking health advice from the CHaPD as required.