[en] White-tailed deer (Odocoileus virgianus) tongues were assayed to assess whether or not significant widespread ¹³⁷Cs contamination occurred in the vicinity of Three Mile Island Nuclear Station as a result of the 1979 accident. White-tailed deer tongues harvested from 10 Pennsylvania counties more than 88 km away from Three Mile Island had significantly higher ¹³⁷Cs levels than deer tongues harvested from counties surrounding the nuclear plant. The mean deer tongue ¹³⁷Cs levels found in Pennsylvania white-tailed deer were lower than ¹³⁷Cs levels found in deer from other parts of the US sampled shortly after culmination of major atmospheric nuclear testing. These findings support the conclusions of previous studies suggesting that only minimal quantities of ¹³⁷Cs escaped from the damaged Three Mile Island plant after the accident