| Abstract
| - While biomagnification of persistent organic pollutants(POPs) in aquatic food chains is well documented, therehave been few investigations of the trophodynamics of POPsin Arctic terrestrial food chains. This study presents field-collected concentration data and corresponding fugacitiesof various hydrophobic organic chemicals (ranging in octanol−water partition coefficients or KOW from approximately103.8 to 109) in two lichen species (Cladina rangiferina andCetraria nivalis), willow leaves (Salix glauca), barren-ground caribou (Rangifer tarandus), and wolves (Canislupus) from Canada's Central and Western Arctic region.The results show that, in contrast to aquatic food chains,persistent substances including β-hexachlorocyclohexaneand 1,2,4,5-tetrachlorobenzene with a KOW<105 cansubstantially biomagnify in lichen−caribou−wolf foodchains in Canada's Central and Western Arctic. Strongpositive correlations between the biomagnification factorand the octanol−air partition coefficients (KOA) ofnonmetabolizable compounds were observed in wolves.In caribou, the biomagnification factors dropped slightly withincreasing KOA. KOA proved to be a better indicator ofbiomagnification than KOW. Current management policiesthat consider only chemicals with KOW values >105 asbioaccumulative substances fail to identify substances thathave the potential to biomagnify in Arctic terrestrial foodchains despite a low KOW because of a high KOA.
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