Wild boars that have been exposed to the radiation cloud generated by the Chernobyl nuclear disaster in the 1980s in the former Soviet Union. These boars roam in German forests nearly 950 miles (1,500 kilometres ) from Chernobyl. Yet, a quarter century later, the amount of radioactive cesium-137 within their tissue often registers dozens of times beyond the recommended limit for consumption and thousands of times above normal.

Cesium's half-life is roughly 30 years. High levels of cesium in the body are thought to cause cancers.