The Arctic is covered in permafrost, a large icy expanse that, as the name suggests, remains permanently frozen. At least that was the case until recently. Climate change has caused record-warm temperatures that are slowly thawing the permafrost. And within the icy reserves lies an abundance of mercury ready to be released. That release could have negative health and environmental effects, according to a study published in the journal Environmental Research Letters. There could be a "giant mercury bomb in the Arctic waiting to explode," study co-author Josh Wes said in a statement.
Mercury has been trapped in the Arctic for thousands of years. Natural air currents pick up atmospheric mercury and push it toward the Arctic, where it's "absorbed by plants, which then deposit the toxin in the soil," said Yale Environment 360. The toxic metal poses a threat to both humans and other wildlife. "Mercury builds up in the food chain over time, and continued exposure, even at low levels, can have serious health consequences," said The Independent.
The good news is that mercury poisoning is not necessarily an immediate threat. Mercury takes time to accumulate in the food chain, and the risk from drinking water is minimal.
Still, "for millennia," the Arctic has been "locking away toxic metals and keeping the planet healthy and happy," said Popular Mechanics. "But after two centuries of an unyielding fossil fuel addiction, this particular environmental bill might soon be coming due." | 
