Thirty years after a reactor exploded at the Chernobyl nuclear power plant in Ukraine, radiation is still turning up in some unexpected places: for instance, in the wild boars tramping through the mountains of the Czech Republic — almost a thousand miles away.

These radioactive boars aren’t turning into teenage mutant ninja pigs, but they aren’t safe for eating, either. That’s a problem in a country where boar meat is mixed into stews and goulash. In fact, the wild boars are being irradiated by their own food: the wild mushrooms they depend on during the cold winter months, Reuters reports.

30 years after chernobyl, radiation is still turning in unexpected places

The 1986 nuclear disaster in Chernobyl, Ukraine spewed the radioactive metal cesium-137 into the atmosphere. A small amount blew nearly 1,000 miles west to the Czech Republic, where it settled into the soil. There, mushrooms absorb it. And when a boar eats the mushrooms, the radiation travels up the food chain. A few years ago, a government report revealed that nearby in Germany, about one in three boars killed by hunters were radioactive.

For people, cesium-137 is not safe for consumption. Eating it spreads the radioactive atoms throughout the body, which can up your risk for cancers. Still, if you were to eat some of the radioactive boar meat, the dose is likely low enough you’d probably be OK, Jiri Drapal at the State Veterinary Administration told Reuters. But if you were to eat the cesium-137-flavored meat multiple times a week for months on end, then you might be in trouble.

And, the best bet is not to eat any, which is why food inspectors in the Czech Republic screen wild meat before it goes to market. They discovered that nearly half of the 614 pigs inspected between 2014 and 2016 were too radioactive to eat. The hazardous meat is banned from use, so if you visit the Czech Republic and eat wild boar goulash, you should be safe.