Bioaccumulation in Terrestrial Systems

Transfer of Organic Pollutants from Air to Terrestrial Biota 

Experimentally determined air-plant equilibrium partition coefficients of SOCs as well as of other organic compounds are rather scarce. Note that, in the following, 

Since the composition of the various plants tested was not determined (i.e., lipid, cutin, lignin), the differences cannot be examined in light of variable contributions. Nevertheless, the substantially different slopes observed indicate that not only the quantity but also the quality of the plant biomass was important in determining air-plant partitioning. Note that a very similar interspecies variability has been observed for the same plants in a field study (Bohme et al., 1999). 

The second important result is the strong temperature dependence of KUp. For example, for PCB52 and PCB153, the model compounds that we focused on to 

Convert concentration to partial pressure by first converting it to mol L-1 (division by the molar mass, M see Appendix C) and subsequent multiplication by RT (2.35 x 106 Pa L.mor1 at 10°C)  

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Trabalka JR, Garten CT Jr. 1981. Development of predictive models for xenobiotic bioaccumulation in terrestrial systems. Oak Ridge, TN Oak Ridge National Laboratory, Environmental Sciences Division 2037. ORNL-5869. 

Bioconcentration, Bioaccumulation, and Biomagnification of Nitroaromatic and Nitramine Explosives in Terrestrial Systems... 

This chapter has defined the major processes that contribute to transfer of organic chemicals between the atmosphere and plant canopy systems, reviewed the theoretical underpinnings of the two most important processes, and summarized the available measurements of the mass transfer parameters. It was illustrated that forest canopies can play an important part in the environmental fate of organic contaminants, particularly for those with intermediate Kqa values and high ATaw values, in addition to the more obvious consequences of chemical accumulation in plants for phytotoxicity and bioaccumulation in terrestrial food chains. The methods presented here allow order of magnitude calculations of the most important chemical fluxes and illustrate how they will be influenced by chemical and environmental properties. 

Endrin released to water will adsorb to sediments or bioaccumulate in fish and other aquatic organisms. Both bioaccumulation and biomagnification of endrin were reported to occur in an aquatic laboratory microcosm system (Metcalf et al. 1973). In terrestrial ecosystems, endrin transformation products (endrin ketone, endrin aldehyde, and endrin alcohol) have been measured in plants grown on endrin-treated soil (Beall et al. 1972 Nash and Harris 1973). 

Plant uptake of chlordecone from the soil via the roots, and volatilization of chlordecone from soil with plant uptake via the leaves were found to be negligible in a closed laboratory system using barley seedlings. This indicates that bioaccumulation of chlordecone by plants (lowest on the terrestrial food chain) is very unlikely based on its log soil adsorption coefficient of almost 4.0 (Topp et al. 1986). No information on the uptake of chlordecone by plants under field conditions was located. 

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