Strontium biokinetic model for the lactating woman and transfer to breast milk: application to Techa River studies

Abstract

This paper presents a biokinetic model for strontium metabolism in the lactating woman and transfer to breast milk for members of Techa River communities exposed as a result of discharges of liquid radioactive wastes from the Mayak plutonium production facility (Russia) in the early 1950s. This model was based on that developed for the International Commission for Radiological Protection with modifications to account for population specific features of breastfeeding and maternal bone mineral metabolism. The model is based on a biokinetic model for the adult female with allowances made for changes in mineral metabolism during periods of exclusive and partial breast-feeding. The model for females of all ages was developed earlier from extensive data on 90Sr-body measurements for Techa Riverside residents. Measurements of 90Sr concentrations in the maternal skeleton and breast milk obtained in the1960s during monitoring of global fallout in the Southern Urals region were used for evaluation of strontium transfer to breast and breast milk. The model was validated with independent data from studies of global fallout in Canada and measurements of 90Sr body-burden in women living in the Techa River villages who were breastfeeding during maximum 90Sr-dietary intakes. The model will be used in evaluations of the intake of strontium radioisotopes in breast milk by children born in Techa River villages during the radioactive releases and quantification of 90Sr retention in the maternal skeleton.