Dear EarthTalk: It is true that the carcasses of whales that wash up on shore are considered dangerous to humans because of the amount of toxins and chemicals in their blubber?
—Michael O"Loughlin, Tigard, OR
Whether wildlife officials in a given region consider a dead beached whale a biohazard or not is local decision, but nevertheless experts agree that only trained professionals should go anywhere near a dead wild animal to prevent the spread of bacterial infection alone, no matter whether any industrial pollutants might be oozing out. But regardless, it is true that some types of whales, given their spot at the top of the marine food chain, do harbor chemical pollution in their fatty tissue and organs.
Researchers have found, for instance, that PCBs, dangerous toxins notorious for polluting New York’s Hudson River and long banned in the U.S. are present in the blubber of beluga and orca whales, among others, in amounts—some 80 parts per million—that could kill a person. DDT, a pesticide banned in 1972 in the U.S. for wreaking havoc on bird and other wildlife populations, also still shows up in measurable amounts in whale blubber around the world.
Beyond such well-known pollutants, newer ones are starting to show up in large amounts in the carcasses of beached whales and other top marine predators. Today biologists are most worried about the marked increase in flame retardants (PBDEs) and stain repellents (PFOS) in dead marine mammals. Flame retardants are particularly troublesome because they "seem to travel over long distances in the atmosphere, and some studies have shown that they can be toxic to the immune system and can affect neurobehavioral development," according to a recent report by the Arctic Council, a multilateral international body in charge of overseeing Arctic law and development. The report also noted that PFOS does "not seem to break down under any circumstances," meaning it is passed up the food chain to whales and other top predators, and then in some cases consumed by humans, especially indigenous Arctic people still hunting marine animals as part of their subsistent lifestyles.