title: Distribution of total mercury, methyl mercury and selenium in pod of killer whales (Orcinus Orca) stranded in the northern area of Japan: comparison of mature females with calves.
abstract: Total mercury (T-Hg) and selenium (Se) concentrations in liver, kidney and muscle from a pod of killer whales including five mature females and three calves stranded in the northern area of Japan were analyzed. In the mature female, contamination level of T-Hg in the liver sample (62.2+/-21.9 microg/wet g) was markedly higher than that in kidney sample and muscle sample. The molar ratio of T-Hg to Se in the liver sample was approximately 1, and those in the kidney and muscle samples were markedly lower than 1. These results suggest that the formation of HgSe compound increases the hepatic accumulation of mercury (Hg). In contrast, contamination level of T-Hg in the calf organs was much lower than that in the mature female organs. These results suggest that the transfer of Hg from the mother to the fetus via placenta and/or to calf via milk is trace.
authors.affiliation: Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293, Japan. endotty@hoku-iryo-u.ac.jp <endotty@hoku-iryo-u.ac.jp>
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Endo
authors.forename: Osamu
authors.initials: O
authors.lastname: Kimura
authors.forename: Yohsuke
authors.initials: Y
authors.lastname: Hisamichi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Minoshima
authors.forename: Koichi
authors.initials: K
authors.lastname: Haraguchi
authors.forename: Chiharu
authors.initials: C
authors.lastname: Kakumoto
authors.forename: Mari
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D005260:Female; D007564:Japan; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008297:Male; D008628:Mercury / Q000032:analysis / Q000633:toxicity; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity*; D008767:Methylmercury Compounds / Q000032:analysis / Q000633:toxicity; D009132:Muscles / Q000737:chemistry; D009792:Oceans and Seas; D012643:Selenium / Q000032:analysis / Q000633:toxicity; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D050685:Whale, Killer / Q000378:metabolism*
chemical_list: D019216:Metals, Heavy; D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury; D012643:Selenium