Uranium and Thorium Decay Series Radionuclides in Human and Animal Foodchains—A Review

Human exposures along plant and animal pathways to isotopes of U, Th, Ra, Pb, and Po are reviewed. The range and variability of intakes among human populations resulting from dietary sources are presented. Also discussed are the sources of intake among farm animals reared for consumption. Under most circumstances, the soil‐plant‐human pathway is the predominant route of intake for humans and livestock. Radionuclide distributions within livestock and human tissues, and the transfer factors used to model intakes along various food chain pathways are summarized. Bone is the major site of deposition in livestock and humans. Where possible, summary data and conclusions from previous reviews are considered along with some notable gaps in the data base for natural series radionudides.