Paper No. J05062 of the Journal of the American Water Resources Association (JAWRA). Discussions are open until February 1, 2008.
Mercury Accumulation in Periphyton of Eight River Ecosystems1
Version of Record online: 28 JUN 2007
JAWRA Journal of the American Water Resources Association
Volume 43, Issue 4, pages 957–968, August 2007
How to Cite
Bell, A. H. and Scudder, B. C. (2007), Mercury Accumulation in Periphyton of Eight River Ecosystems. JAWRA Journal of the American Water Resources Association, 43: 957–968. doi: 10.1111/j.1752-1688.2007.00078.x
- Issue online: 28 JUN 2007
- Version of Record online: 28 JUN 2007
- Received May 13, 2005; accepted November 13, 2006.
Abstract: In 2003, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program and U.S. Environmental Protection Agency studied total mercury (THg) and methylmercury (MeHg) concentrations in periphyton at eight rivers in the United States in coordination with a larger USGS study on mercury cycling in rivers. Periphyton samples were collected using trace element clean techniques and NAWQA sampling protocols in spring and fall from targeted habitats (streambed surface-sediment, cobble, or woody snags) at each river site. A positive correlation was observed between concentrations of THg and MeHg in periphyton (r2 = 0.88, in log-log space). Mean MeHg and THg concentrations in surface-sediment periphyton were significantly higher (1,333 ng/m2 for MeHg and 53,980 ng/m2 for THg) than cobble (64 ng/m2 for MeHg and 1,192 ng/m2 for THg) or woody snag (71 ng/m2 for MeHg and 1,089 ng/m2 for THg) periphyton. Concentrations of THg in surface-sediment periphyton had a strong positive correlation with concentrations of THg in sediment (dry weight). The ratio of MeHg:THg in surface-sediment periphyton increased with the ratio of MeHg:THg in sediment. These data suggest periphyton may play a key role in mercury bioaccumulation in river ecosystems.