| Abstract
| - Plant uptake of semivolatile organic compounds (SOCs)occurs primarily from the atmosphere via one of threeprocesses: equilibrium partitioning between the vegetationand the gas phase, kinetically limited gaseous deposition,or wet and dry particle-bound deposition. Each of theseprocesses depends on different atmospheric concentrations,plant properties, and environmental variables. Hence, ininterpreting measurements of SOCs in plants, it is imperativethat the major process responsible for the accumulationof a given compound be known. Beginning with basicequations describing gaseous and particle-bound depositionto vegetation, a framework for identifying the majoruptake process and further interpreting measurements ofplant concentrations is developed. This frameworkmakes use of the relative differences in accumulationbehavior as a function of the octanol−air partition coefficient(KOA) of the chemical. The mathematical analysis leadsto two interpretive tools, both log−log plots, one of thequotient of the vegetation and gas-phase concentrationsvs KOA and one of the quotient of the vegetation and particle-bound concentrations vs the quotient of the particle-bound and gaseous concentrations. Each of these plotscontains three distinct and easily recognizable segments,and each segment corresponds to one of the threedeposition processes. When the experimental data areplotted and the three segments are identified, it is possibleto determine the dominant uptake process for a givencompound, and this in turn opens the door to furtherinterpretation of the plant uptake behavior.
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