IDENTIFICATION OF REFERENCE VALUES FOR METALS IN GENERAL-POPULATION GROUPS - THE EXAMPLE OF CADMIUM

The study investigates a group of 449 blood donors not occupationally exposed to metals living in the Brescia area known for its metal industry. Besides the common clinical and biochemistry tests, the most important toxic metals were determined, in particular cadmium. Due to the wide variation of metal values in biological media a very rigid selection was made on the basis of a detailed case history in order to exclude any form of exposure to metals. We thus selected a subgroup of 188 subjects to whom CdB levels were significantly lower and less dispersed than in the other subgroup. A similar behaviour was also observed for other metals such as lead. This study also confirms that it is necessary to take into account other variables which may influence the Cd monitoring parameters, independent of environmental or occupational exposure. In particular, it can be seen that the CdB levels were higher in males and in smokers and were not influenced by alcohol consumption. The mean CdB values observed in Brescia differed slightly from those found in two other neighbouring cities in Northern Italy. It is perhaps very difficult especially for the evaluation of slight absorption of heavy metals, to consider reference values obtained in different regions of the same country. © 1990, Taylor & Francis Group, LLC. All rights reserved.