Radioactive wild boars have been roaming the forests Germany decades. Scientists believed their radioactivity was due to the 1986 Chernobyl nuclear disaster. However, the animals' radioactivity has long mystified scientists because while levels radioactive caesium other animals has decreased the years, radioactivity wild boars has persisted high levels. Scientists have dubbed this mystery the "wild boar paradox". New research now attributes the contamination Germany's wild boars to nuclear weapons tests the mid-20th century. The Chernobyl reactor produced caesium-137, which has a much shorter life than the caesium-135 created nuclear weapons.
Scientists believe the reason wild boars have remained so radioactive compared to other forest creatures is their love the delicacy truffle mushrooms. Radioactive particles accumulate these underground fungi, which form part the boars' diet. The high levels of caesium boars make the animals too dangerous to be eaten German law. This has resulted a reduction in the hunting of the animals, which has led to a proliferation their numbers. Geochemist James Kaste asks why the effects nuclear weapons testing the environment have been "under-studied and largely forgotten". He said: "This is one the ultimate case studies showing how legacy soil pollution can haunt generations to come."