Relative Importance of Inhalation and Ingestion as Sources of Uptake of 210Pb from the Environment

Abstract

Dietary intake of 210Pb is generally higher than inhalation intake, but fractional uptake to blood is higher from inhalation. In this study publications are reviewed in which both inhalation and ingestion intake of 210Pb are measured. Concentrations of 210Pb in bone are also given, where available. Up-to-date biokinetic information on Pb is used to evaluate fractional uptake from inhalation and ingestion, including consideration of the effect of aerosol particle size. Estimates are also given of 210Pb uptake from domestic radon, alcoholic beverages and smoking. The difficulty in obtaining precise estimates of 210Pb uptake is emphasised. On average, atmospheric inhalation, diet and domestic radon contribute 12, 86 and 2% of total 210Pb uptake respectively. Alcoholic beverages and cigarettes can add a further 75%. Average committed effective dose from one year of 210Pb intake to adults is 37 �Sv, while committed dose equivalents to organs range widely from 380 �Sv for bone surfaces to 5 �Sv for most soft tissue reflecting the heterogeneous tissue distribution of Pb.