A recent paper, “Observed in-plume gaseous elemental mercury depletion suggests significant mercury scavenging by volcanic aerosols” authored by Alkuin M. Koenig et al., has illuminated the obscure pathways through which mercury journeys within volcanic environments.
Volcanoes have long been known to emit mercury, a potent neurotoxin, into the atmosphere. However, the post-emission behaviour and transformations of mercury in a volcanic plume, an extreme and chemically active environment, remain mostly unknown. Such transformations are important as they determine if mercury is transported globally or deposited regionally. Here we present experimental evidence that, within a volcanic plume, mercury can get efficiently converted into forms that sediment quickly and are washed out by rain. This implies that terrestrial volcanism may directly emit mercury into the atmosphere and indirectly remove it. While this would reduce the atmospheric mercury burden, it would also increase mercury deposition and human exposure in volcanically active regions.
The link to the article on the publisher’s site:
https://pubs.rsc.org/en/content/articlelanding/2023/ea/d3ea00063j