As if rising sea levels weren’t already enough of a threat…

It’s believed the region could be a “global Hg sink as prevailing atmospheric circulation carries Hg to northern latitudes”, the study says. 
Typically rivers would contain about “a salt grain-sized amount of mercury” for every Olympic-sized swimming pool of water – about 2.5 million litres. Mercury in the Greenland glacial meltwater rivers was found in concentrations up to 15 times that, and 200 times more was found in glacial flour – sediment created when a glacier scrapes across bedrock. 
“We didn’t expect there would be anywhere near that amount of mercury in the glacial water there,” said Rob Spencer, associate professor of earth, ocean and atmospheric science at Florida State University. 
“Naturally, we have hypotheses as to what is leading to these high mercury concentrations, but these findings have raised a whole host of questions that we don’t have the answers to yet.”
Such high concentrations are unlikely to be from human activity, they said, because there is much more mercury in the rivers than surrounding snow and ice, inconsistent with a pollution source, which would be less discriminate in its spread. 
“We’ve learned from many years of fieldwork at these sites in western Greenland that glaciers export nutrients to the ocean, but the discovery that they may also carry potential toxins unveils a concerning dimension to how glaciers influence water quality and downstream communities,” said University of Bristol glaciologist Jemma Wadham.