This research is directed towards developing predictive models of the fate and accumulation of metals in benthic aquatic animals (e.g., crab, lobster, and benthic fishes) that are consumed by humans and may therefore represent an increased risk to public health. Metals released from Superfund sites may be stored in the sediments to elevated concentrations thereby representing a route of potentially higher doses of metals to humans than from drinking water. Also, the benthic biomass may significantly influence the time of recovery and bioavailability of metals at a site due to sediment mixing (bioturbation). With calibrated predictive modeling tools available, a more credible basis can then be established for estimating the effectiveness of remedial actions. The specific aims of this research are to: (1) construct a generic model of metal accumulation in aquatic food webs with sediment interaction, (2) develop physiologically based toxicokinetic models of uptake and disposition of metals in benthic animals, (3) develop a modeling framework for the effect of sediment bioturbation due to benthic biomass on the flux of cadmium from sediments, and (4) apply the fate and accumulation modeling framework to cadmium in the blue crab of a Superfund site at Foundry Cove. These models will be calibrated using: (1) existing data from Superfund and other sites for the generic model of metals transfer, (2) laboratory data to be obtained by other components on Cd uptake in benthic invertebrates and Cd disposition in blue crab, Atlantic tomcod and killifish for use in the generic model and the PB-TK modeling, (3) data from measurements of Cd flux in the laboratory with varying densities of benthic biomass to develop the model of Cd flux due to bioturbation and (4) existing data to be supplemented by field work at Foundry Cove to calibrate the modeling framework of Cd in the blue crab under field conditions.
NIH ExPorter
NIH ExPorter