Poison ice

As the sea ice melts, a toxic stew of mercury and synthetic chemicals is seeping into the Arctic food web, harming the area’s people. We may be next.

… As the Amundsen cuts through ice across the top of the globe, Carrie and his fellow researchers are uncovering evidence of a disturbing fallout of climate change. They are finding toxic contaminants, some at remarkably high levels, accumulating in this remote and visually pristine environment. Although there are no industrial sources in the Arctic, residents of the Far North have some of the world’s highest levels of mercury exposure, some well above what the World Health Organization considers safe. High levels of mercury — a powerful neurotoxin — are being found in Arctic marine wildlife, including ringed seals and beluga whales, both staples of the traditional Northern diet. Levels in Arctic beluga have increased markedly in recent years.

… As temperatures rise, causing sea ice, permafrost and snow to melt, the mercury that had been frozen in place is now being released, causing exposure up and down the food web. “Climate change alters exposure in the north and increases the system’s vulnerability,” says Robie Macdonald, a research scientist with Canada’s Department of Fisheries and Oceans.

Yet the Arctic researchers are routinely recording a lot more than mercury. They are seeing synthetic chemicals such as the brominated flame retardants known as PBDE’s (used in upholstery, textiles and plastics), as well as perfluorinated and chlorine compounds. And while long banned in many countries, lingering amounts of DDT and PCBs continue to turn up in people and animals in the Far North. Of concern due to their persistence and ability to accumulate in plant and animal tissue — particularly the fat prevalent in Arctic animals — these chemicals are also known to disrupt the endocrine hormones that regulate reproduction and metabolism. Some are considered carcinogens.

Salon.com