Scientists have finally determined why wild boars in Germany are still showing signs of radioactivity, and it has to do with their diet in addition to the aftereffects of nuclear weapon testing and the Chernobyl disaster. History’s worst man-made disaster occurred in 1986, yet the level of radioactivity found in these wild boars hasn’t gone down — something experts are now attributing to truffles.

Bavarian Boars

A large area of Europe, including Bavaria in Southwestern Germany, was affected by nuclear fallout after the Ukrainian power plant exploded nearly 40 years ago. Elements from the reactor, such as cesium-137, can survive for decades. And it does not hit its half-life for approximately 30 years. That may seem like a long time, but it’s not if you compare it to cesium-135, which has a half-life of 2.3 million years!

Chernobyl-related contaminants in a variety of species have dropped in Bavarian forests over the past six decades. Scientists however, have not seen a decrease in radioactive levels in boars. Since cesium-137 has a half-life of 30, there was some confusion as to why these boars continue to show such high levels of contamination. There is even a term for this phenomenon: the wild boar paradox.

To determine the reason for this paradox, scientists examined the bodies of 48 boars in 11 Bavarian districts from 2019 and 2021. A study published in the journal Environmental Science and Technology concludes that nuclear weapons testing during the Cold War and radioactivity from Chernobyl led to a buildup of contaminants in fungi, including deer truffles, that the boar like to eat.

Toxic Truffles

To figure out the specific source of the radioactivity, scientists examined the ratio of cesium-135 to cesium-137. A high ratio of cesium-135 to cesium-137 signals that nuclear weapon explosions are the source; whereas a low ratio points to nuclear reactors.

Researchers used soil samples from Chernobyl and Fukushima in addition to human lung tissue from 1960s Austria. They compared them to the isotopic fingerprint of the boar meat. The lung tissue showed signs of contaminants from Cold War nuclear weapons testing. The weapons were not detonated at the study site, indicating that fallout from the nuclear tests traveled in the atmosphere.

The destroyed Chernobyl reactor, one of four units operating at the site in Ukraine in 1986. Credit: IAEA Imagebank Via Wikimedia Commons (CC BY-SA 2.0).

Eighty-eight-percent of the samples surpassed the acceptable limit for radioactive cesium in Germany. Nuclear weapons testing was responsible for 10–68 percent of the contamination. Scientists concluded that underground truffles absorbed the toxins from both the weapons testing and the Chernobyl incident.

According to researchers, “This study illustrates that strategic decisions to conduct atmospheric nuclear tests 60–80 years ago still impact remote natural environments, wildlife, and a human food source today.”

Want More?

Are you curious about what is still standing nearly 40 years after the Chernobyl nuclear power plant disaster? In addition to structures related to the reactor itself, there’s actually a nearby amusement park that is still partially intact! Check out the video below to learn more.

There is something morbidly fascinating about nuclear weapons and disasters. That’s why Ripley’s Believe It or Not! recently added to it’s own collection a piece of nuclear history: a graphite disc from Chicago Pile-1 — the world’s first artificial nuclear reactor!

Every Ripley’s Believe It or Not! is filled with historical artifacts — visit a location near you and see what you can uncover!

By Noelle Talmon, contributor for


Discover hundreds of strange and unusual artifacts and get hands-on with unbelievable interactives when you visit a Ripley’s Odditorium!