State Water Resources Research Institute Program

Project ID: 2007ME148B
Title: Using reactive thin-film membranes and Molecular Tools to determine mercury mobility and transformation in the Penobscot River estuary sediment, Maine
Project Type: Research
Start Date: 4/01/2008
End Date: 3/31/2009
Congressional District: 2
Focus Categories: Geochemical Processes, Toxic Substances, Sediments
Keywords: Biomonitoring, Contaminant Transport, Estuaries, Geochemistry, Heavy Metals, Membranes, Rivers, Toxic Substances
Principal Investigators: Amirbahman, Aria; Diehl, Melinda
Federal Funds: $ 9,800
Non-Federal Matching Funds: $ 20,625
Abstract: The inland and coastal waters in Maine have been subject to decades of anthropogenic mercury (Hg) loading. Consequently, aquatic biota have accumulated some of the highest Hg body burdens in the United States. Of particular concern is the bioavailability and geochemical cycling of Hg in estuaries which is controlled by both biotic and abiotic processes. Hg transformation and shifts in Hg mobility within estuaries occur rapidly under changing redox conditions driven by tides. Measuring Hg fluxes in estuaries is difficult due to redox sensitivity, high spatial heterogeneity, and the low concentrations at which Hg is present. We have developed a thin-film membrane that can increase the spatial and temporal resolution of Hg measurement in sediments. The membranes have been tested in the lab and show a high uptake capacity and fast uptake kinetics. We propose to deploy the membranes in the contaminated sediments of the Penobscot River estuary to measure Hg flux, and to provide quantitative information regarding the lability of the sediment Hg and methylmercury (MeHg) pools. In addition, molecular analyses will be conducted to characterize the microbial processes that lead to mobilization and transformation of Hg species. Combined, these two approaches provide mechanistic insight into the mobility and bioavailability of sediment Hg, two characteristics that affect Hg bioaccumulation. This will be a collaborative effort between the Department of Civil Engineering at the University of Maine and the Microbiology/ Molecular Ecology Team at the USGS that will contribute to future remediation and sustainable fisheries efforts.

Progress/Completion Report, PDF

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Earl Greene
Page Last Modified: Tuesday, 15-Jan-2013 00:12:56 EST