[Monitoring biological lead in Silesian populations with particular reference to elementary school children].

The national production of lead is concentrated in the Katowice region (voivodship). Another harmful factor observed in this area is a high intensity of motor transport. Hence, high contamination of air and surface layers of soil, particularly in the Upper Silesian Industrial District. The main objective of this work was to review the results of surveys of lead concentrations in the blood (Pb-B) of children and adults living in this area. The presented results of biological monitoring of lead were obtained from cohort, prospective and cross-sectional studies of groups of primary school children and their mothers, carried out by the Regional Sanitary and Epidemiological Station during the years 1981-1990 (N = 4570) as well as from examinations performed in 283 children (1-15 age group) by the Silesian Medical Academy and in 1028 children (1st and 8th grades of school) by the Institute of Environmental Protection. The concentration of lead was measured in samples of venous blood using atomic absorption spectrophotometry. The Regional Sanitary and Epidemiological Station Laboratory involved in Pb-B measurements has successfully participated in the interlaboratory programme of quality assurance. The results indicated that the contamination of the environment with lead in the Katowice region is very much diversified, and, in general, three areas can be identified: 1. The vicinity of large industrial emissions of lead, where mean Pb-B concentrations were usually twice as high as in rural areas of the Katowice voivodship. In many cases the lead blood concentrations exceeded the safe limit of 19 micrograms/dl and the excess varied in time. 2. Large industrial urban agglomerations of the Upper Silesian Industrial District. The Pb-B concentrations in children living in this area were higher by 50% in comparison with rural areas. The excess of safe limit (19 micrograms/dl) was, however less frequent that in the area described above. 3. Rural areas. But even in those areas not all Pb-B concentrations were fully acceptable. A continuous biological monitoring of lead in representative samples of the population living in this area is necessary to obtain completely reliable assessment of exposure to lead in the Katowice voivodship.