Iodine-131 in Thyroids of the Meadow Vole (Microtus pennsylvanicus) in the Vicinity of the Three Mile Island Nuclear Generating Plant

Abstract
Meadow voles (Microtus pennsylvanicus) were trapped in the vicinity of Three Mile Island Nuclear Power Station between 6 and 16 April 1979. Thyroids of voles caught 1.9 km from the reactor (Site III) contained significantly higher amounts of 131I than those of voles caught further away. This is in agreement with Dept. of Energy predictions that this site was contaminated to a greater degree than the other two sites sampled. The highest level of 131I detected from Site III was 11.4 pCi/thyroid and the mean for that site was 5.6 pCi/thyroid. The vole is proposed as a monitoring organism for 131I contamination of ecosystems.