Heavy metal contamination status of Japanese cranes (Grus japonensis) in east Hokkaido, Japan--extensive mercury pollution.
Japanese cranes (Grus japonensis) of eastern Hokkaido, Japan, and migrants between the Amur River basin and the eastern China-Korea Peninsula, live around fresh and brackish wetlands. Only a few thousand cranes are confirmed to exist in the world, so they are under threat of extinction. To understand the adverse effects of metal accumulation, we measured concentrations of three heavy metals in the liver, kidney, and muscle of 93 Japanese cranes from Hokkaido. The cranes were classified into six categories according to their sex and three life stages. Cadmium and mercury (Hg: total mercury) showed age-dependent but not sex-dependent accumulation in the liver and kidney. Twenty cranes showed 30 microg/g or higher levels of Hg in dry tissue and five adult cranes had more than 100 microg/g in their livers or kidneys. Cadmium concentrations were generally lower in all samples. Two adult cranes showed extremely high lead levels of more than 30 microg/g in their livers, suggesting lead poisoning. These results have highlighted the widespread and high levels of Hg pollution in Japanese cranes in Hokkaido, Japan.
Teraoka
Hiroki
H
Department of Toxicology, School of Veterinary Medicine, Rakuno Gakuen University, Midori-cho, Ebetsu 069-8501, Japan. hteraoka@rakuno.ac.jp
Kumagai
Yoshihiro
Y
Iwai
Hisae
H
Haraguchi
Kensaku
K
Ohba
Takashi
T
Nakai
Kunihiko
K
Satoh
Hiroshi
H
Sakamoto
Mineshi
M
Momose
Kunikazu
K
Masatomi
Hiroyuki
H
Hiraga
Takeo
T
D000818:Animals; D001717:Birds; D008628:Mercury / Q000493:pharmacokinetics / Q000633:toxicity*; D019216:Metals, Heavy / Q000493:pharmacokinetics / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics / Q000633:toxicity*
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D008628:Mercury