Observed and predicted gradient in deciduous tooth Pb indices for constant or for mixed high and low blood Pb profiles

The district of Hoboken near Antwerp (Belgium) is located mainly at the northeast (NE) of an important smelter of non-ferrous metals. A total of 399 deciduous tooth samples of various tooth types from children aged 5-13 years at various distances from the plant were gathered during two successive surveys. The first covers the cumulative period of exposure from 1968 to 1980-82, while the second concerns the period from 1974 to 1986. The epidemiological data are expressed as ppm Pb year-1, by reference to the period of time encountered from given tooth calcification stages (tooth age). The annual lead accumulation in the NE sector is found to be a decreasing exponentially function with distance, and gradually reaching base-line values. In the 2nd survey the frequency distributions moved to lower indices, with a complex influence of age-related decreasing transfer coefficients and of decreasing external dust contamination. On the other hand, determination of the relation between deciduous tooth lead data and blood lead profiles allowed here to calculate tooth lead indices modelling typical blood lead profiles. A constant high blood lead level is compared to situations with higher blood lead preceding lower ones (profile A), or with lower blood lead preceding higher ones (profile B).SCOPUS: cp.p