title: Selenium in brown bears (Ursus arctos) from Croatia: Relation to cadmium and mercury.
abstract: Muscle (n = 111), liver (n = 111), and kidney cortex (n = 101) samples from brown bears (Ursus arctos) were collected in the 2009 and 2010 hunting seasons in Croatia and analysed for selenium (Se), cadmium (Cd), and total mercury (Hg). The aim was to assess the levels of these elements according to age, sex, and season of collection, and to investigate possible Se/Cd and Se/Hg interactions. Median Se concentrations were 0.139 μg/g in muscle, 0.409 μg/g in liver and 1.75 μg/g wet mass in kidney cortex. Median Cd and Hg were 0.0078 and 0.0018 μg/g in muscle, 1.09 and 0.031 μg/g in liver, and 16.5 and 0.206 μg/g wet mass in the renal cortex, respectively. Se/Cd molar ratios were less than 1 in the kidney cortex, and close to or above 1 in liver and muscle, respectively. Toxic Cd and Hg correlated with Se in all of the studied tissues. Sex differences were found for all three elements (except Se in liver), with females having higher tissue concentration than males. Only Cd showed age-dependence. Bear samples collected in fall had higher Se in muscles, and Hg in muscles and liver compared to samples collected in spring. Element concentrations in brown bear tissues were within the range of previously reported studies. Bear meat is considered a rich source of Se, safe for consumption with regard to its Cd and Hg content. According to the molar ratio and correlation results, we assume that Se binding is not the primary detoxification pathway for Cd and Hg in brown bears.
authors: a Analytical Toxicology and Mineral Metabolism Unit, Institute for Medical Research and Occupational Health , Zagreb , Croatia.
authors: Maja
authors: M
authors: Lazarus
authors: Ankica
authors: A
authors: Sekovanić
authors: Slaven
authors: S
authors: Reljić
authors: Josip
authors: J
authors: Kusak
authors: Jelena
authors: J
authors: Kovačić
authors: Tatjana
authors: T
authors: Orct
authors: Jasna
authors: J
authors: Jurasović
authors: Đuro
authors: Đ
authors: Huber
mesh_terms: D000818:Animals; D002104:Cadmium / Q000032:analysis* / Q000378:metabolism; D017523:Croatia; D005260:Female; D007668:Kidney / Q000737:chemistry / Q000378:metabolism; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008297:Male; D008628:Mercury / Q000032:analysis* / Q000378:metabolism*; D009132:Muscles / Q000737:chemistry / Q000378:metabolism; D012643:Selenium / Q000032:analysis / Q000378:metabolism; D001503:Ursidae / Q000378:metabolism*
chemical_list: D002104:Cadmium; D008628:Mercury; D012643:Selenium
keywords: Croatia; Selenium; brown bear (Ursus arctos); cadmium; mercury