Harvard study finds circumpolar rivers most responsible for high levels of mercury in the Arctic
Environmental scientists at Harvard have discovered that the Arctic accumulation of mercury, a toxic element, is caused by both atmospheric forces and the flow of circumpolar rivers that carry the element north into the Arctic Ocean.
While the atmospheric source was previously recognized, it now appears that twice as much mercury actually comes from the rivers.
The revelation implies that concentrations of the toxin may further increase as climate change continues to modify the region’s hydrological cycle and release mercury from warming Arctic soils.
“The Arctic is a unique environment because it’s so remote from most anthropogenic (human-influenced) sources of mercury, yet we know that the concentrations of mercury in Arctic marine mammals are among the highest in the world,” says lead author Jenny A. Fisher, a postdoctoral fellow in Harvard’s Atmospheric Chemistry Modeling Group and the Department of Earth and Planetary Sciences (EPS). “This is dangerous to both marine life and humans. The question from a scientific standpoint is, where does that mercury come from?”