Organochlorine pesticide, polychlorinated biphenyl and heavy metal concentrations in wolves (Canis lupus L. 1758) from north-west Russia

The wolf Canis lupus is a major terrestrial predator in eastern Europe and, as a top carnivore, may be exposed to high concentrations of contaminants that are readily transferred through the food chain. Despite this, there ar e few published data on pollutant and pesticide levels in wolves. This stud y utilised tissues from animals legally killed by hunters for other reasons (animals were not killed for the purposes of this study) to carry out the only detailed investigation of contaminants in wolves in Europe and the fir st in animals from Eastern Europe. The livers of 58 wolves from the Tver an d Smoliensk regions of northwest Russia (54 degreesN 31 degreesE to 57 degr eesN 35 degreesE) were analysed for seven organochlorine pesticides, 24 PCB congeners, Aroclor 1254-matched summed PCBs (Sigma PCBs), total mercury, c admium and lead. Cadmium, most of the organochlorine pesticides and many PC B congeners were not detectable in any of the wolves. Hexachlorobenzene, al pha-HCH, pp'DDE, PCB congeners 118, 138, 149 and 156 and lead were detected in up to 6% of livers. Dieldrin, PCB congeners 153, 170 and 180, Sigma PCB s and mercury were detected more frequently. Contaminant levels were genera lly low; maximum wet weight concentrations of any of the organochlorine pes ticides, Sigma PCBs and mercury were less than 0.1, 1 and 0.25 mug g(-1), r espectively. PCB congeners 153, 170 and 180 accounted for 41% of the Sigma PCBs. Dieldrin, Sigma PCBs and mercury concentrations did not vary signific antly between males and females nor between adult and juvenile ( < 12 month s old) wolves apart from the Sigma PCB concentration, which was on average five times higher in adults than juveniles. Liver residues were generally b elow the level normally associated with adverse effects except for lead lev els which exceeded the critical 5 mug g(-1) dry wt. ;concentration in three of the 58 animals examined. (C) 2001 Elsevier Science B.V. All rights rese rved.