Abstract

Emission rates of gaseous monomethylmercury (CH(3)Hg(II)), as well as elemental mercury(Hg(0)) and dimethylmercury [(CH(3))(2)Hg(II)], were determined in Hg-contaminated water-sediment microcosms (duplicates of three treatments) by gaseous species-specific isotope dilution analysis (SSIDA). Incubation of similar to 500 g (wet mass) of sediments containing 30 mu mol of ambient Hg with an addition of 2.6 mu mol of (201)Hg(II) tracer resulted in average (n = 6) gaseous emissions of 84 +/- 26, 100 +/- 37, and 830 +/- 380 pmol of ambient CH(3)Hg(II), CH(3)(201)Hg(II), and (201)Hg(0), respectively, during 108 days of incubation. In contrast to Hg(0), a transient temporal pattern was observed for measured CH(3)Hg(II) emission rates, which peaked at day 12 and decreased to much lower levels by the end of the experiments. At day 12, CH(3)Hg(II) constituted 30-50% of the total emitted gaseous Hg, emphasizing the significance of this species to total Hg emissions from anoxic sediment-water systems. Emission rates of gaseous CH(3)Hg(II) did not reflect the accumulated CH(3)Hg(II) content in the sediment suggesting that emissions mainly originated from newly methylated Hg(II). Speciation modeling of the pore water suggests that CH(3)Hg(II) was emitted as CH(3)HgSH(0)(g).

Published in

Environmental Science and Technology
2010, Volume: 44, number: 1, pages: 278-283
Publisher: AMER CHEMICAL SOC

SLU Authors

• Skyllberg, Ulf

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1021/es9020348

Permanent link to this page (URI)

https://res.slu.se/id/publ/48792