Near surface oxidation of elemental mercury leads to mercury exposure in the Arctic Ocean biota.

ABSTRACT: Atmospheric mercury (Hg(0), Hg(II)) and riverine exported Hg (Hg(II)) are proposed as important Hg sources to the Arctic Ocean. As plankton cannot passively uptake Hg(0), gaseous Hg(0) has to be oxidized to be bioavailable. Here, we measured Hg isotope ratios in zooplankton, Arctic cod, total gaseous Hg, sediment, seawater, and snowpack from the Bering Strait, the Chukchi Sea, and the Beaufort Sea. The Δ²⁰⁰Hg, used to differentiate between Hg(0) and Hg(II), shows, on average, 70% of Hg(0) in all biota and differs with seawater Δ²⁰⁰Hg (Hg(II)). Since Δ²⁰⁰Hg anomalies occur via tropospheric Hg(0) oxidation, we propose that near-surface Hg(0) oxidation via terrestrial vegetation, coastally evaded halogens, and sea salt aerosols, which preserve Δ²⁰⁰H

SUBMITTER: Lim SH 

PROVIDER: S-EPMC11365953 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature