EN
The lead, mercury, zinc, copper and iron contents in muscles, kidneys and livers of 340 horses were examined in the years of 1980, 1982 and 1989. Samples for analysis were taken from 10 slaughterhouses located in different regions of Poland. The mean Pb concentration was 0.086 mg/kg in muscles, 0.34 mg/kg in kidneys, 0.43 mg/kg in livers. Hg concentrations were low in all analyzed tissues and mean value was 0.003 mg/kg in muscles, 0.086 mg/kg in kidneys and 0.012 mg/kg in livers. Zinc, copper and iron levels were within the range of physiological concentrations. The lead and mercury concentrations in horse kidneys and livers from the industrial regions were significantly higher than those in the same organs from the agricultural regions.