To ask the Secretary of State for Social Services what are the average levels of strontium 90 present in the bone marrow of children of the same age, born and raised in the United Kingdom, at intervals of five years from 1975 to the present; and whether the figures are based on actual measurements or from estimates from air and food levels.
I am not aware of measurements or estimates which provide the information requested. Strontium 90 if found principally in bone rather than the bone marrow. The National Radiological Protection Board has made estimates for adults of radiation dose from strontium 90; these estimates are of notional lifetime dose from a particular year's intake. They are derived, using mathematical models, from measurements of levels of Strontium 90 in the diet.