Uptake of Sediment-Associated Contaminants by the Deposit-Feeding Amphipod Leptocheirus Plumulosus (Shoemaker): Effects of Natural Sediment Qualities
EPA Grant Number: GF9500166Title: Uptake of Sediment-Associated Contaminants by the Deposit-Feeding Amphipod Leptocheirus Plumulosus (Shoemaker): Effects of Natural Sediment Qualities
Investigators: Schlekat, Christian
Institution: University of South Carolina at Columbia
EPA Project Officer: Broadway, Virginia
Project Period: June 1, 1995 through January 1, 2000
Project Amount: $29,280
RFA: STAR Graduate Fellowships (1995)
Research Category: Academic Fellowships , Fellowship - Ecology , Ecological Indicators/Assessment/Restoration
Description:
Objective:The primary focus of this research is to determine if contaminants associated with labile forms of sediment organic carbon are more bioavailable to deposit feeders than those associated with refractory organic carbon. A second consideration is whether contaminants with different binding affinities exhibit variable bioavailability for a given organic carbon source. Third, the research seeks to determine if patterns distinguishable within the first two objectives are consistent among different deposit feeders. The general methodology will be as follows. Test organisms will be exposed to a number of sediment treatments. The nature of the sediment treatments will generally entail coating sediment particles with a uniform layer of different classes of organic carbon. Radio-labeled contaminants will be used to facilitate detection and quantification of uptake. Organic contaminants will be labeled with 14C, a beta-emitter. Metal experiments will utilize a gamma emitter specific for the element in question. The relative attraction of contaminants for each organic coating will be measured by mixing coated particles with contaminants at constant temperature, pH, and salinity. treatments will be offered to test organisms under controlled experimental conditions for a discrete time period. Experimental animals will be allowed to feed ad libitum during the feeding period. Nonionic organic contaminants are lipophilic; therefore, the "biota sediment accumulation factor" (BSAF), which normalizes for both organism lipid content and sediment organic carbon content will be determined for experiments involving organic contaminants.
Supplemental Keywords:Ecosystem Protection/Environmental Exposure & Risk, Water, Scientific Discipline, Waste, RFA, Ecosystem/Assessment/Indicators, Biology, Ecology, Microbiology, Analytical Chemistry, Chemistry, Ecological Indicators, Biochemistry, Environmental Engineering, Environmental Microbiology, Environmental Chemistry, Ecological Effects - Environmental Exposure & Risk, Ecosystem Protection, Contaminated Sediments, Ecology and Ecosystems, deposit feeders, uptake of sediment associated contaminants