Good analogy. However, South Korea has come to a different conclussion and banned any fish from the region .
Lack of transparency would really hurt Japanese. They are covering up the true extent of the problem. Even Japanese shy away from domestic catches. Won't blame foreigners to do the same.
If one lives in U.S., the argument of drop in the bucket may fly, but not in E. Asia. S. Korean gov acted because public fear recently rose and as a result local fish industry is dying. They don't know if fish is from Japan or not. They want to filter out Japanese fish. It is all due to lax inspection of Japanese fish and ongoing coverup of real situation at Fukushima plant.
Things are not moving in favorable direction for Japanese. It could be a matter of time before S. Korea bans all marine product from Japan.