HC Deb 07 July 1982 vol 27 c147W
Mr. Dubs

asked the Secretary of State for Social Services whether he plans to announce any changes in the maximum blood lead level he considers safe; and on what scientific evidence this is based.

Mr. Kenneth Clarke

No. There is no convincing evidence that harm is caused at blood lead levels below 35 microgrammes per decilitre. A confirmed blood lead level over 25 microgrammes per decilitre, however, suggests the likelihood of exposure to a particular source of lead in the immediate locality which should be dealt with in the usual way.