Despite being heavily contaminated with high dosages of residual nuclear radiation, this species of catfish, which frankly look like eels with catfish heads aren’t actually mutated. They’ve just be allowed to grow so larger because their isn’t a species of predator large enough to feed on them nearby. Add in the fact that they’re something of a tourist attraction in Pripyiat, Chernobyl, and that’s why these strange fish have been able to get freakishly large.
I wouldn’t eat that if I were you.