§ Mr. Newensasked the Secretary of State for Education and Science 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 1945 until the present.
Mr. MoneyRadiation damage to bone marrow arises primarily from irradiation of the marrow by strontium-90 in the adjoining bony tissue. There is no direct information on strontium-90 levels in human bone marrow but data on the levels in bony tissue between 1959 and 1970 were published in the Medical Research Council's Monitoring Report Series, and between 1955–56 and 1959 by the United Kingdom Atomic Energy Authority. No measurements on bone618W were made before 1955 but environmental levels were extremely low before 1954. The bone samples were from individuals who died in the United Kingdom but there is no information on where they were born and raised. Mean levels of strontium-90 in samples from children up to five years of age—excluding still-births and neonatal deaths—are given below for approximate intervals of five years up to 1970:
Year Bone Sr-90 concentration (picocuries per gram calcium) 1945 … … — 1950 … … Very low 1956* … … 0.8 1960 … … 2.9 1965 … … 6.6 1970 … … 2.1 * No figures available for 1955. Collection of bone samples stopped after 1970 because information accumulated over the previous 15 years had revealed that the strontium-90 level in bone could be estimated satisfactorily if general environmental levels in air, vegetation and milk were known.