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(83-17) Prediction of Bioaccumulation and Uptake Dynamics of Persistent Organic Pollutants by Bacteria and Phytoplankton. Del Vento, Sabino1, Dachs, Jordi*,1, 1 Dept. Environmental Chemistry, IIQAB-CSIC, Barcelona, Spain ABSTRACT- Phytoplankton and Bacteria play an important role on the biogeochemical cycles of persistent organic pollutants (POPs). However, experimental data and quantitative knowledge of the kinetics of uptake and depuration of most POPs by bacteria and phytoplankton are scarce. In the present communication, a procedure to predict the sorption kinetics to bacteria and phytoplankton is developed. The prediction method is the combination of a mechanistic model for sorption and quantitative structure activity relationships relating bioconcentration factors and membrane permeability to the chemical physical-chemical properties. The model consists of two compartments where the first compartment is the cellular surface and the second compartment is the cell biomass or matrix. Equations for estimating uptake and depuration rate constants into the matrix and adsorption and desorption rate constants onto the surface are obtained. These expressions depend upon the physical-chemical properties of the chemical, the environmental temperature, the microorganism size and species specific quality of organic matter. Uptake, depuration, adsorption and desorption rate constants are estimated for POPs such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polychlorinated dioxins and furans and POPs of emerging concern such as polybrominated diphenyl ethers. Finally, implications of uptake and depuration dynamics on the biogeochemical cycling of POPs are discussed. Key words: persistent organic pollutants, uptake, bacteria, phytoplankton |
