HC Deb 25 April 1994 vol 242 c35W
Mr. Flynn

To ask the Secretary of State for the Environment (1) whether water purification processes are able to remove drug residues from water supplies;

(2) what evidence he has of the presence of residues from (a) the contraceptive pill and (b) Diazepam tranquillisers in water supplies; and what assessment he has made of the dangers associated with such contamination;

(3) what residues from drugs are most commonly detected in British water supplies; and what are the dangers associated with such contamination.

Mr. Atkins

The Department has commissioned surveys of concentrations of drugs residues in rivers and in river-derived water supplies. Survey data have also been provided to the Department by water companies and research organisations.

Drugs residues, including components of the birth control pill, pain killers and tranquillisers have been detected only infrequently and at very low concentrations in a few rivers. The concentrations of all residues were found to be several orders of magnitude lower than levels that might be expected to cause adverse effects. These already insignificant concentrations are further reduced during water treatment. Diazepam and other drugs residues have not been detected in water supplies.