title: Accumulation of persistent organic pollutants in parasites.
abstract: Organisms are simultaneously exposed to various stressors, including parasites and pollutants, that may interact with each other. Research on the accumulation of organic compounds in host-parasite systems is scant compared to studies on parasite-metal interactions and mainly focuses on intestinal endoparasites. We reviewed factors that determine the accumulation of persistent organic pollutants (POPs) in host-parasite systems. The wet/dry weight-based concentration of POPs in these parasites is usually lower than that in host tissues because of lower lipid contents in the parasites. However, the fractionation of the pollutants into parasites and their hosts may vary, depending on developmental stages in the life cycle of the parasites. Developmental stages determine the trophic relationship and the taxon of the parasite in the host-parasite systems because of different feeding strategies between the stages. Lipid-corrected concentrations of organic chemicals in the host are usually higher than those in the endoparasites studied. This phenomenon is attributed to a number of physiological and behavioural processes, such as feeding selectivity and strategy and excretion. Moreover, no significant relationship was found between the accumulation factor (i.e. the ratio between the lipid-corrected concentrations in parasites and in their hosts) for polychlorinated biphenyls and either hydrophobicity or molecular size. At the intermediate hydrophobicity, larger and more lipophilic compounds are accumulated at higher levels in both parasites and the host than smaller and less lipophilic compounds. The bioaccumulation of POPs in parasites is affected by some other abiotic, e.g. temperature, and biotic factors, e.g. the number of host species infected by parasites.
authors.affiliation: Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, The Netherlands. Electronic address: YenLe@science.ru.nl.
authors.forename: T T
authors.initials: TT
authors.lastname: Yen Le
authors.affiliation: Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, The Netherlands.
authors.forename: Laurie
authors.initials: L
authors.lastname: Rijsdijk
authors.affiliation: Department of Aquatic Ecology and Centre for Water and Environmental Research (ZWU), University of Duisburg Essen, Germany.
authors.forename: Bern
authors.initials: B
authors.lastname: Sures
authors.affiliation: Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, The Netherlands.
authors.forename: A Jan
authors.initials: AJ
authors.lastname: Hendriks
mesh_terms: D000818:Animals; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D006790:Host-Parasite Interactions; D009930:Organic Chemicals / Q000032:analysis / Q000378:metabolism*; D010271:Parasites / Q000502:physiology*; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism
chemical_list: D004785:Environmental Pollutants; D009930:Organic Chemicals; D011078:Polychlorinated Biphenyls
keywords: Accumulation; Hydrophobicity; Lipid content; Organic compounds; Parasite; Trophic level