That is problem exactly.
It is very bad but I see no reason it should suddenly get magnitudes worse. It has, is and will continue to pump radioactive poison into the Pacific and that is a very huge amount of water. Unfortunately, the currents bring it right by Alaska, Western Canada California some of the very richest fishing water in the word. Too many population crashes of different species to be coincidence, IMO.
Lets put it this way, I will continue to buy kelp from Iceland.