The “Wild Boar Paradox”

Bavaria, a state in southeast Germany, has long been the site of a conundrum for scientists. The wild boars (Sus scrofa) native to Bavaria have long had elevated levels of radiation. Let’s specifically focus on Cesium, an element in the sixth row of the periodic table with radioactive isotopes associated with nuclear weapons. The half-life (the time it takes for half of a sample of a radioactive material to decay) of Cesium-135, the isotope of Cesium associated with nuclear weapon explosions, is 2.3 million years. Meanwhile, Cesium-137, associated with nuclear reactors such as the infamous Chernobyl nuclear accident in 1986, has a half-life of 30 years.

Ever since the Chernobyl disaster, Bavarian boars have had high radioactivity levels, leading researchers to hypothesize that the source of it was Chernobyl. However, 30 years having passed since the disaster, the radiation levels within the boars ought to be declining. But they aren’t.

A 2023 study in the journal Environmental Science and Technology may have found the solution. Radioactive debris from both nuclear weapons tests during the Cold War as well as Chernobyl have accumulated in fungi that are consumed by the wild boars. Between 2019 and 2021, the authors analyzed the flesh composition of 48 individual boars, comparing the ratio of Cesium-135 to Cesium-137. Considering the unique sources of each of these isotopes, the scientists found that most flesh samples had more radioactive Cesium than German law permits.

Ultimately, they concluded that nuclear tests from nearly a century ago still have profound impacts on wildlife and natural environments today. As humans’ carbon footprint emerges as one of the world’s greatest concerns, it’s something we need to keep in mind as we look to a more sustainable future.

Author: Arjun Puri

Reference: Scientists finally figured out what's making German wild boars radioactive, and it's not just Chernobyl. (2023). Retrieved 7 September 2023, from https://www.livescience.com/animals/land-mammals/scientists-finally-figured-out-whats-making-german-wild-boars-radioactive-and-its-not-just-chernobyl

Nuclear Weapons Testing and Chernobyl Incident Leads to Radioactive Boars in Germany. (2023). Retrieved 7 September 2023, from https://www.onegreenplanet.org/animals/radioactive-boars-contaminated-truffles/

Stäger, F., Zok, D., Schiller, A. K., Feng, B., & Steinhauser, G. (2023). Disproportionately High Contributions of 60 Year Old Weapons-137Cs Explain the Persistence of Radioactive Contamination in Bavarian Wild Boars. Environmental science & technology, 10.1021/acs.est.3c03565. Advance online publication. https://doi.org/10.1021/acs.est.3c03565

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