Doesn’t radiation concentrate in the tissues of sea life in in increasingly higher levels the further up the food chain an animal is?
Yes. Higher up the food chain, the higher the total amount concentrated. You can thank all the microrganisms that love finding metal in the ocean water.
Bottom line is do not go near dead ocean animals on the beach that the land scavengers are eating.
Btw - The Japanese just found a ocean fish with an incredily high concentration. More then 100 times legal limit. Was found near a freshwater stream entrance.