Factors Affecting Bioconcentration

Eadie, B.J., W.R. Faust, P.F. Landrum, and N.R. Morehead. 1984. Factors affecting bioconcentration of PAH by the dominant benthic organisms of the Great Lakes. Pages 363-377 in M. Cooke and A.J. Dennis (eds.). Polynuclear Aromatic Hydrocarbons Mechanisms, Methods and Metabolism. Battelle Press, Columbus, OH. 

Vigano, L., Galassi, S., Gatto, M. (1992) Factors affecting the bioconcentration of hexachlorocyclohexanes in early life stages of Oncorhynchus mykiss. Environ. Toxicol. Chem. 11, 535-540. 

Terrestrial wildlife movements are such that site-specific tools are more efficiently used to refine exposure estimate. In this case, site-specific exposure estimates are used and compared with safe thresholds for toxicity, termed toxicity reference values (TRVs). Toxicity reference values for wildlife have been developed for energetic compounds. This chapter presents a brief overview of the processes used to establish these tools for ERA for explosives and related soil contaminants that are frequently of potential ecological concern at the affected military sites. This chapter also provides recommendations for use of these values in the ERA process. Investigations addressing the importance and extent of habitat disturbance as a component of the ERA process on explosives-contaminated ranges are reviewed in Chapter 11. General bioaccumulation principles and applications of the bioaccumulation factor and bioconcentration factor (BAF and BCF, respectively) concepts that are often employed in the ERA process to determine bioaccumulation potential of MC for terrestrial receptors are reviewed in Chapter 10. 

PAHs are widely distributed in the environment as evidenced by their detection in sediments, soils, air, surface waters, and plant and animal tissues. However, the ecological impact of PAHs is uncertain. PAHs show little tendency for bioconcentration despite their high lipid solubility (Pucknat 1981), probably because most PAHs are rapidly metabolized. Sims and Overcash (1983) list a variety of research needs regarding PAHs in soil-plant systems. Specifically, research is needed to establish the rates of PAH decomposition in soils the soil PAH levels above which PAH constituents adversely affect the food chain and enhancement factors that increase degradation rates of PAHs, especially PAHs with more than three rings. Once these factors have been determined, PAH disposal into soils may become feasible at environmentally nonhazardous levels. 

Water solubility is one of the major parameters which affect the fate and distribution in the environment. Hydrophobic compounds with high octanol-water partition coefficients tend to bio accumulate. Opperhuizen and Voors [63] have shown that hydrophobicity of PCDEs determines the bio concentration factor of PCDEs and that bioconcentration kinetics of PCDEs resemble those of PCBs. 

In this paper we have discussed the factors that may affect the linear correlation between bioconcentration factors in fish and the 1-octanol/water partition coefficient. Since a lipid/water partitioning process is the principal process controlling the uptake of organic chemicals from the water, the same factors may also affect other QSARs in aquatic toxicology. 

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