Parasites Suck Toxins From Sharks

Parasitic worms inside the guts of sharks are absorbing high concentrations of toxic heavy metals, researchers have found. The worms could be useful to scientists trying to check up on the health of ocean waters. And they could be saving the sharks from metal poisoning u" at least for now. "What we are seeing with these parasites is a classic canary in a coal mine situation," says Kenneth MacKenzie, a parasitologist at the University of Aberdeen. "If the parasites start dying off as a result of metal poisoning we will know that levels have gone too high and can expect larger species to start suffering too"...