ICRP recommends fractional absorption changes

The International Commission on Radiological Protection (ICRP) has now recommended adoption of the values and procedures proposed in ICRP publication 48, 'The metabolism of plutonium and related elements'. Publication 48 proposed changes in the fractional absorption (f1) values of actinides from the gastrointestinal tract and their retention in the liver, skeleton and gonads after absorption. A comparison of proposed values for f1 with those recommended previously by ICRP for radiation workers is given in tabular form. The proposed changes mainly affects the isotopes of plutonium of long physical half life, where the annual limits of intake need to be decreased by almost a factor of 10. (UK)