Sedimentary antimony stable isotope record of anthropogenic contamination in a karst lake in southwestern China.

Anthropogenic sources of antimony (Sb) are an important driver of pollution in the Earth environment, but their roles in the historical changes of Sb pollution in lake ecosystems are currently poorly understood. This study documents the sedimentary Sb deposition fluxes in Hongfeng lake (HFL), in southwestern China during 1958-2021 and quantifies the changes of anthropogenic contributions to sediments using Sb stable isotopes. Mean Sb concentration (mean: 1.

Dissociation of Mercuric Oxides Drives Anomalous Isotope Fractionation during Net Photo-oxidation of Mercury Vapor in Air.

The atmosphere is the primary medium for long-distance transport and transformation of elemental mercury (Hg), a potent neurotoxin. The recent discovery of mass-independent fractionation (MIF) of even-mass Hg isotopes (even-MIF, measured as ΔHg and ΔHg) in the atmosphere is surprising and can potentially serve as a powerful tracer in understanding Hg biogeochemistry. Far-ultraviolet (UVC) light-induced gas-phase reactions have been suspected as a likely cause for even-MIF, yet the mechanism remains unknown.

Quantification of Atmospheric Mercury Deposition to and Legacy Re-emission from a Subtropical Forest Floor by Mercury Isotopes.

Air-soil exchange of elemental mercury vapor (Hg) is an important component in the budget of the global mercury cycle. However, its mechanistic detail is poorly understood. In this study, stable Hg isotopes in air, soil, and pore gases are characterized in a subtropical evergreen forest to understand the mechanical features of the air-soil Hg exchange.