title: Assessment of plant uptake models used in exposure assessment tools for soils contaminated with organic pollutants.
abstract: The aim of this study was to evaluate and improve the accuracy of plant uptake models for neutral hydrophobic organic pollutants (1 < logK(OW) < 9, -8 < logK(AW) < 0) used in regulatory exposure assessment tools, using uncertainty and sensitivity analyses. The models considered were RAIDAR, EUSES, CSOIL, CLEA, and CalTOX. In this research, CSOIL demonstrated the best performance of all five exposure assessment tools for root uptake from polluted soil in comparison with observed data, but no model predicted shoot uptake well. Recalibration of the transpiration and volatilisation parameters improved the performance of CSOIL and CLEA. The dominant pathway for shoot uptake simulated differed according to the properties of the chemical under consideration; those with a higher air-water partition coefficient were transported into shoots via the soil-air-plant pathway, while chemicals with a lower octanol-water partition coefficient and air-water partition coefficient were transported via the root. The soil organic carbon content was a particularly sensitive parameter in each model and using a site specific value improved model performance.
authors.affiliation: Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science, University of Reading , Reading, RG6 6DW, United Kingdom.
authors.forename: Koki
authors.initials: K
authors.lastname: Takaki
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Wade
authors.forename: Chris D
authors.initials: CD
authors.lastname: Collins
mesh_terms: D002138:Calibration; D002244:Carbon / Q000032:analysis; D004781:Environmental Exposure / Q000032:analysis*; D057927:Hydrophobic and Hydrophilic Interactions; D008962:Models, Theoretical; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000378:metabolism; D018526:Plant Transpiration / Q000187:drug effects; D010944:Plants / Q000187:drug effects / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics*; D035501:Uncertainty
chemical_list: D012987:Soil; D012989:Soil Pollutants; D002244:Carbon