In sweden they use to feed raindeers with hey two weeks before slauther until abuot 10 tears ago to lower the becuerel level. We also have a spring season to avoid mushroom eating roedeer in august, levels are much lower now adays.

There is a direct correlation between mushrooms available and radioactivity in wild boar. These mushrooms seem to accumulate radioactive substances and wild boar like them, especially the subterranean truffles.

Of course, this applies only areas originally affected by the Tchernobyl fallout.

Interestingly, the (n fact very low degree of) radioactivity rises towards mushroom season anf drops again afterwards. In other words, it does nor accumulate in wild game's organisms.