2003 Volume 56 Issue 12 Pages 825-830
PIXE assays performed to survey heavy-metal contamination in liver, kidney, and hair samples collected from 42 Japanese black bears (male: 24, female: 18) in Iwate Prefecture detected chromium, manganese, iron, cobalt, copper, zinc, selenium, molybdenum, cadmium, lead, etc. Cobalt concentrations in the bear tissues were more than 10 times higher than those in human or several other animal species. In two bears, extraordinarily high concentrations of zinc, especially in the hair, suggested excess exposure to this element. Mean cadmium concentration in the liver was 0.20 mg/kg, in the kidneys 9.16 mg/kg, and in the hair 2.10 mg/kg. In no case cadmium concentrations exceeded those in normal healthy adult Japanese human beings. Whereas hepatic lead concentrations were below lmg/kg in most animals, in three bears they were above 2mg/kg. These high lead concentrations may be caused by environmental contamination in the Iwate area.