Global Warming

A Devastating Toxin Is Bubbling Up From the Permafrost

Trapped in all the permafrost encircling the northern reaches of the globe is an estimated 30 billion tons of carbon. It’s an unfathomable amount. But there’s something else lurking in the permafrost that has the potential to be more immediately dangerous to the people and wildlife living in the area: mercury.

Wildfires and volcanoes belch mercury, and, since the Industrial Revolution, so do coal-burning power plants and factories. Warm-air currents carry mercury in its inorganic heavy-metal form to the Arctic, where it settles into the soil and vegetation before being safely locked away in the deeply frozen permafrost.

In its inorganic form, mercury is less threatening to people. But as the permafrost thaws, mercury is finding its way into the soil and the region’s many ponds, rivers, and lakes. Once there, certain microbes can convert inorganic mercury into the form to be concerned about: neurotoxic methylmercury.