Global Warming Causes Toxic Mercury Leakage from Arctic Permafrost

The thawing of Arctic permafrost due to climate change is releasing significant amounts of toxic mercury into the environment.

This sudden release of mercury in large amounts into the atmosphere from the permafrost regions is described (by researchers) as a “Mercury Bomb”.
As permafrost thaws due to climate change, it could release a huge amount of mercury, which might have serious health impacts locally, regionally, and even globally.
The results highlighted the importance of accurately capturing the dynamics of erosion and deposition for understanding mercury transport in Arctic rivers and how they will evolve in a changing climate.

In a study published in Environmental Research Letters, researchers investigated the rate at which mercury trapped in Arctic permafrost is being released from the Yukon River basin in Alaska.
Their goal was to assess how soon a potential ‘mercury bomb’ could be triggered.
To gain insight into the effects of erosion in the Yukon River basin, floodplain sediments were collected from two sites with discontinuous permafrost: – Beaver and Huslia (Alaska) between June and September

The study discovered that mercury content was generally higher in finer sediment grains compared to coarser ones.
This finding suggests that certain soil types could pose greater environmental risks.
Abrupt thawing events, such as landslides in the Arctic permafrost region, can quickly mobilize large deposits of sediment, potentially releasing significant mercury stores.

Indigenous communities in the Arctic, particularly those in Alaska, are among the most exposed to mercury.
These communities rely on subsistence fishing, which has led to disproportionately high blood mercury levels due to dietary exposure.
Changes in mercury levels in Arctic waterways directly impact these communities, as well as the broader Arctic ecosystem and ocean.

The study highlighted an example of thaw slump landslides in the terrestrial Arctic’s permafrost region adjacent to a tributary of the Mackenzie River in Canada.
According to a study published in Nature Reviews Earth & Environment in March 2022, over 98% of atmospheric mercury is emitted outside the Arctic and transported there via long-range air and ocean pathways.

It is a heavy metal, a global contaminant that poses significant health and environmental risks.
While it occurs naturally, human activities have greatly increased its presence in the environment.

Natural: Volcanoes, geothermal springs, ocean emissions
Human Activities: Burning coal, waste incineration, industrial processes, mining, dental amalgams.