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Polar bears (Ursus maritimus Phipps, 1774) are exposed to heavy metal and lipophilic contaminants that are known to bioaccumulate and biomagnify. Few studies concurrently report both chemical classes in the same individuals and are thus unable to assess drivers of observed tissue concentrations, and the potential adverse biological responses to combined exposures. We examined blood concentrations of mercury (Hg) and the sum of seven polychlorinated biphenyls (Σ7PCB) from free-ranging Southern Beaufort Sea polar bears to assess which factors contributed to variations among cohorts (adult males, adult females, young) during spring. Concentrations of Hg ranged from 10.3 to 228.0 ng/g wet mass, but mean concentrations were similar between males and females independent of age. Concentrations of Σ7PCB (range 2.0-132.8 ng/g wet mass) were greater among females and young than among males. Toxicant concentrations were related to packed cell δ[sup.15]N, an estimate of trophic position, after the inclusion of packed cell δ[sup.13]C. Concentrations of Σ7PCB were also positively correlated with concentrations of neutral lipids (triglycerides and free fatty acids) and inversely correlated to body condition indices. Elevated concentrations of toxicants and lower body condition indices in females and young compared with males may be a sentinel to a changing arctic environment. Further assessment of the potential adverse health impacts of contaminants and nutritional stress in these cohorts is warranted. Les ours polaires (Ursus maritimus Phipps, 1774) sont exposes a des metaux lourds et a des contaminants lipophiles qu'on sait soumis a la bioaccumulation et a la bioconcentration. Peu d'etudes traitent a la fois de ces deux classes chimiques chez un meme individu et sont donc incapables d'evaluer les facteurs explicatifs des concentrations observees dans les tissus et les reactions biologiques adverses potentielles a ces expositions combinees. Nous avons mesure les concentrations sanguines de mercure (Hg) et d'un ensemble de sept biphenyles polychlores (Σ7PCB) chez des ours polaires en liberte dans le sud de la mer de Beaufort afin d'evaluer les facteurs qui contribuent aux variations entre les cohortes (adultes males, adultes femelles, oursons) au printemps. Les concentrations de Hg varient de 10,3 a 228,0 ng/g masse fraiche, mais les concentrations moyennes sont semblables chez les males et les femelles, independamment de l'age. Les concentrations de Σ7PCB (etendue 2,0-132,8 ng/g masse fraiche) sont plus elevees chez les femelles et les jeunes que chez les males. Les concentrations de produits toxiques sont reliees au δ[sup.15]N des globules compactes, une estimation de la position trophique, apres l'inclusion du δ[sup.13]C des globules compactes. Les concentrations de Σ7PCB sont aussi en correlation positive avec les concentrations de lipides neutres (triglycerides et acides gras libres) et en correlation inverse avec les coefficients de condition corporelle. Des concentrations elevees de produits toxiques et des coefficients de condition plus faibles chez les femelles et les jeunes par comparaison avec les males peuvent jouer le role de sentinelle pour le changement dans l' environnement arctique. Il y a lieu de faire des evaluations supplementaires des effets nefastes potentiels de ces contaminants et des stress alimentaires sur la sante de ces cohortes. [Traduit par la Redaction], Introduction Many contaminants undergo long-range transport from southern latitudes and are deposited in arctic ecosystems via biota, air, and water (Macdonald et al. 2005; Swain et al. 2007). Climate changes [...]

Macaques are similar to humans both physiologically and behaviorally. In South and Southeast Asia they are also synanthropic, ecologically associated with humans. Synanthropy with humans raises the possibility that macaques come into contact with anthropogenic toxicants, such as lead and mercury, and might be appropriate sentinels for human exposures to certain toxic materials. We measured lead (Pb) and mercury (Hg) levels and characterized the stable isotopic compositions of [delta][sup.15]N and [delta][sup.13]C in hair from three groups of free-ranging macaques at the Swoyambhu temple in Kathmandhu, Nepal, an urban population that has abundant contact with humans. Hair lead levels were significantly higher among young macaques and differed among the three groups of macaques that were sampled. Hair Hg levels were low. No statistical association was found between stable isotopic compositions ([delta][sup.15]N and [delta][sup.13]C) and Pb and Hg levels. Our data did not find evidence that lead levels were associated with diet. We conclude that, in this population of macaques, behavioral and/or physiologic factors may play a significant role in determining exposure to lead. Chemical analysis of hair is a promising, noninvasive technique for determining exposure to toxic elements in free-ranging nonhuman primates. Am J Phys Anthropol 142:453-460, 2010. [c]2009 Wiley-Liss, Inc. KEY WORDS lead; macaque; ecotoxicology; mercury; synanthropic DOI 10.1002/ajpa.21247