Thawing Arctic Permafrost Hides a Toxic Risk: Mercury, in Massive Amounts
Rising temperatures are waking a sleeping giant in the North—the permafrost—and scientists have identified a new danger that comes with that: massive stores of mercury, a powerful neurotoxin, that have been locked in the frozen ground for tens of thousands of years.
The Arctic's frozen permafrost holds some 15 million gallons of mercury. The region has nearly twice as much mercury as all other soils, the ocean and the atmosphere combined, according to a new study published Monday in the journal Geophysical Research Letters.
That's significantly more than previously known, and it carries risks for humans and wildlife.
"It really blew us away," said Paul Schuster, a hydrologist at the U.S. Geological Survey in Boulder, Colorado, and lead author of the study.
US Geological Survey