PRAGUE (Reuters) - The Czech Republic has an unusual problem this winter with its wild boar meat, a local delicacy. The boars are radioactive.

Actually, it’s not the boars themselves, but what they’re eating. A cold and snowy winter is forcing them to feed on false truffles, an underground mushroom common in the Sumava mountain region shared by Czechs, Austrians, Germans - and wild boars.

The mushrooms can absorb high levels of the radioactive isotope Caesium 137. And three decades ago the nuclear catastrophe at Chernobyl released a fair amount of Caesium 137 that eventually drifted down on the Sumava mountains.

Now the boars are eating the mushrooms, and ingesting the Caesium 137 along with them. That’s making their meat radioactive, Jiri Drapal at the State Veterinary Administration told Reuters.

“It is more or less a seasonal issue,” Drapal said.

But it’s a long season. The half life of Caesium 137 is 30 years - that is, it takes 30 years for the radioactivity of the isotope to fall to half its original value. Then another 30 to fall to half again, and so on. The boars could be glowing for quite a while.

“We can expect to find (affected) food for a number of years from now,” Drapal said.

And that could cause some problems with the supply of boar meat, which is popular in the Czech Republic. It often shows up on restaurant menus in goulash, a thick stew of meat, sauce and dumplings.

Any boar that ends up as goulash ought to be safe. Every wild animal hunted, not only boars, must be inspected before its meat can get to customers. Radioactive meat is banned from circulation, Drapal said.

That’s the good news. The bad news is that 614 animals were inspected from 2014 to 2016, and 47 percent were above the limit - almost half.

The semi-good news is that even meat from radioactive animals would be a health hazard only in large doses, Drapal said. You would have to eat it several times a week for couple of months, to get sick, he said.