Environmental Health - Toxic Substances
Biodynamic Model is Unraveling the Complexities of Metal Bioaccumulation from Contaminated Sediments
Three scenarios of potential selenium discharges and bioaccumulation that could result from a proposed extension of the San Luis Drain, California. The DYMBAM model was used as part of a larger model to develop the scenarios of effects in the San Francisco Bay, California (figure taken from USGS Fact Sheet 2004-3091).
Water resource managers use various ecological risk assessment methodologies to assess
A key factor controlling the outcome of these risk assessments is the rate that metals are bioaccumulated by affected organisms. The only problem is that metal bioaccumulation is highly variable due to differences among species, the environmental chemistry or bioavailability of metals, and the complexities of the cycling of metals in aquatic ecosystems. USGS scientists and their colleagues have developed a biodynamic model of bioaccumulation (DYMBAM) that can be used to predict the bioaccumulation of metal contaminants in affected organisms, such as clams and ducks. The model is "biodynamic" in the sense that
In short, it’s a biodynamic model because a biological approach is used rather than a strictly chemical approach.
Biodynamics can be viewed as a unifying concept that can explain why species differ in magnitude and patterns of metal bioaccumulation and why bioaccumulation differs widely among metals. The biodynamic approach has been used to help water resource managers make decisions involving contaminated sediments in the San Francisco Bay, California, area. For example:
Luoma, S.N., and Rainbow, P.S., 2005, Why is metal bioaccumulation so variable? Biodynamics as a unifying concept: Environmental Science and Technology, v. 39, no. 7, p. 1921-1931, doi:10.1021/es048947e.
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