§ 40 and 41. Mr. S. O. Davies
asked the Minister of Health, as representing the Minister for Science, (1) if he will give the comparative figures for the atomic 77W fall-out for the first half of 1958 and 1959 in terms of radioactive strontium and caesium in Great Britain's water supplies; (2) if he will make a statement on the increasing quantities of strontium and caesium in United Kingdom water supplies.
§ Mr. Walker-Smith
The figures are published in the Report of the Atomic Energy Authority entitled "Radiostrontium and Radiocaesium in Drinking Water in the United Kingdom", a copy of which is in the Library of the House. They show that in the half year referred to radioactivity in surface drinking water was approximately double that in the corresponding period in 1958. The main reason for the increase was probably the increased fall-out due to the Soviet Arctic tests in October, 1958. The contribution of drinking water to the intake of radioactive fall-out by human beings continues to represent a very small percentage of the total.