Particles and vegetation: implications for the transfer of particle-bound organic contaminants to vegetation

This paper presents a comprehensive review of the mechanisms responsible fo r the transfer of atmospheric particulate deposition and soil particulate r e-suspension onto vegetation. The nature of atmospheric aerosols and dry/we t particulate deposition are reviewed, together with information from the l iterature on radionuclides as tracers of the air particle/soil particle to vegetation transfer processes. Information from these fields is used to mak e inferences about the potential significance of these pathways in supplyin g particle-bound semi-volatile organic chemicals (e.g, polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlo rinated biphenyls) to vegetation. Retention of compounds on particles broug ht to the above-ground plant surfaces is discussed. In the absence of defin itive field/experimental studies, calculations are made drawing on the lite rature data to estimate the contributions of atmospheric and soil particle- bound organic contaminants to the plant concentration. These show that depe nding on the site-specific, species-specific and compound-specific scenario s considered, particulate-bound inputs may be negligible or may dominate th e supply of organic contaminants to the above-ground portion of plants. How ever, field/experimental studies and direct measurements are needed to prov ide reliable quantitative data on this topic. (C) 2000 Elsevier Science B.V . All rights reserved.