Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Published Online September 13, 2007
Science DOI: 10.1126/science.1148050

Research Articles

Submitted on July 19, 2007
Accepted on September 5, 2007

Mass-Dependent and -Independent Fractionation of Hg Isotopes by Photoreduction in Aquatic Systems

B. A. Bergquist 1 and J. D. Blum 1

1 Department of Geological Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI, 48109 USA.

Hg isotopes can be used as tracers of Hg biogeochemical pathways in the environment. Photochemical reduction of aqueous Hg species by natural sunlight leads to both mass dependent fractionation (MDF) of Hg isotopes and mass independent fractionation (MIF) of the odd mass isotopes, with the relationship between the MIF for the two odd isotopes being distinct for different photo-reduction pathways. Large variations in MDF and MIF are observed in fish and provide new insights into sources and bioaccumulation of Hg in food webs. MIF in fish can also be used to estimate the loss of methylmercury via photo-reduction in aquatic ecosytems.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Variations in 238U/235U in uranium ore deposits: Isotopic signatures of the U reduction process?.
C. J. Bopp IV, C. C. Lundstrom, T. M. Johnson, and J. J.G. Glessner (2009)
Geology 37, 611-614
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)