CADMIUM LEVELS IN KIDNEYS FROM SWEDISH PIGS IN RELATION TO ENVIRONMENTAL-FACTORS - TEMPORAL AND SPATIAL TRENDS

The kidney cadmium level in pigs slaughtered at the age of 5-7 months was analysed with respect to geographical and temporal trends. During the period 1984-1992, a total of 1051 samples of porcine kidney from 3 1 abattoirs were analysed for cadmium at the National Food Administrat ion within the control programme for livestock production. The mean ki dney cadmium level was 0.11 +/- 0.07 mg/kg wet wt. (mean +/- S.D.). Re gression analysis showed that the cadmium concentration in pig kidney has increased by 2% per year. By using Geographic Information System ( GIS), geographical trends in cadmium concentration of porcine kidney w ere analysed and correlated to cadmium levels in moss and pH in the mo r layer of podsolized soil. These two parameters explained 60% of the random variation in cadmium levels in porcine kidney. There were signi ficant differences between individual abattoirs, but no significant lo ngitudinal or latitudinal trend was found. Variation in kidney cadmium levers within breeding stocks was investigated. Kidneys from eight st ocks, with five pigs from each, were analysed for cadmium concentratio n. In spite of the homogeneous treatment of the pig within the same st ock, kidney cadmium levels varied on average by a factor of two betwee n individuals. There was a significant correlation between cadmium in feed and cadmium levels in porcine kidney (P = 0.002). The temporal in crease in cadmium levels in porcine kidney should be further investiga ted. An increase in cadmium body burden in pig may be an indicator of an increase in human cadmium exposure. (C) 1997 Elsevier Science B.V.