I cant exactly point you to a specific location but in the mercury poisoned discussion groups they talk about plants and fish that are contaminated by mercury because the oceans are contaminated with mercury themselves. But if you look up lets say "chollera and mercury" it'll say that chollera is a mercury sponge but its weak so once ingested it can release some of the mercury in your body. Some say chollera is a chelator but many that I have talked to say they had negative side effects from it