HC Deb 26 February 1958 vol 583 cc51-2W
Mr. Mason

asked the Minister of Health, as representing the Lord President of the Council, what estimate the Medical Research Council has arrived at in regard to the amount by which radiation must increase before the doubling of the genetic mutation rate takes place.

Mr. Walker-Smith

In their Report on "The Hazards to Man of Nuclear and Allied Radiations" (Cmd. 9780), the Medical Research Council expressed the view that the best estimate it could make, in the light of present knowledge, was that the value of the dose of radiation that would double the mutation rate in general lay somewhere between 30 roentgens and 80 roentgens, although the possibility of it lying outside this range could not be excluded. The data that has become available since the publication of the Report in June, 1956, is in line with this assessment of the situation.

Mr. Mason

asked the Minister of Health, as representing the Lord President of the Council, what recommendations the Medical Research Council has made as regards a safe minimum level of radiation or threshold below which there is no increase of somatic conditions such as leukaemia and bone cancer.

Mr. Walker-Smith

The Medical Research Council does not consider that there is sufficient evidence upon which to express an opinion whether there is a threshold level of radiation below which no increase in somatic conditions, such as leukaemia or bone cancer, is likely to occur.