In the Mountain West, glaciers – large masses of ice and snow accumulated over many years – can be found in mountain ranges in Colorado, Montana, Nevada and Wyoming.
When glaciers melt, these large chunks of snow and ice release sulfate-rich minerals that flow downstream into watersheds. As sulfate accumulates, it can create a potent neurotoxin called methylmercury.
Researchers from the University of Colorado, Boulder tested local soils in nearby mountains to measure for the toxin. They discovered methylmercury in peatlands, which are wetlands consisting largely of organic matter from decaying plants.
In the wetlands above the treeline, there were very low levels of methylmercury. But below the treeline, levels of the toxin were much higher.
This can pollute the wetland’s water, fish and wildlife, said study author Hannah Miller.
“If you are eating out of these ecosystems, or eating downstream, or drinking water downstream from these ecosystems, there could be a direct impact on how much mercury is in your food source and also how much mercury is in your water,” Miller said.
Miller noted the contamination levels were not concerning, but the findings can help land managers monitor climate change’s future impacts on mercury levels.
“This is sort of a good step in the direction of having a better understanding of what is happening in mountain wetlands,” she said. “And what is the potential climate change impact on how mercury moves through those systems?”
The study didn’t include any other parts of the Mountain West, but Miller pointed out that rising temperatures are melting glaciers around the region.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNR in Nevada, KUNC in Colorado and KANW in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.
