§ Mr. PawseyTo ask the Secretary of State for the Environment what latest information he has on the medical effect of excess levels of nitrate on human beings.
§ Mrs. CurrieI have been asked to reply.
The most recent United Kingdom epidemiological study, published in 1986, did not indicate any relationships between exposure to raised levels of nitrate and cancer in humans. Whilst infantile methaemoglobinaemia is known to be caused by high concentrations of nitrate in drinking water, no cases of infantile methaemoglobinaemia attributable to concentrations of nitrate in drinking water have been reported in the United Kingdom since 1975.
Advice on the medical aspects of nitrate in drinking water was last given in a letter from the Government's chief medical officer in November 1985. The Department continues to review all relevant scientific literature including epidemiological studies in other countries, and is presently seeking the advice of the committee on the medical aspects of the contamination of air, soil and water on the findings of studies published since 1985.