NEUROBEHAVIORAL AND NEUROPHYSIOLOGICAL OBSERVATIONS IN 6-YEAR-OLD CHILDREN WITH LOW LEAD LEVELS IN EAST AND WEST-GERMANY

Within a larger comparative environmental health screening program in East and West Germany neurobehavioral and neurophysiological measures were taken in 367 six year old children in Leipzig (N = 179), Gardelegen (N = 68), and Duisburg (N = 120). Lead concentrations from venous blood samples (PbB) ana from deciduous teeth (PbT) were measured as markers of environmental lead exposure by electrothermal AAS. Dependent variables included four subtests from NES1 (tapping, reaction time, pattern comparison, and Benton visual retention), as well as VEP-latencies (N-2, P-100, N-3) evoked by checkerboard patterns of different size and contrast. The overall median blood; lead-concentration was 5 mu g/dl (range: 1.3 - 19.0 mu g/dl), and the corresponding tooth lead-concentration was 2 mu g/g (0.2 - 1.4 mu g/g). The 95-percentile of the overall frequency distribution for PbB was below 10 mu g/dl. Associations between markers of lead-exposure and neurobehavioral or neurophysiological outcome were assessed by means of multiple linear or logistic regression analyses. After adjusting for relevant confounders/ covariates significant (p < 0. 05) Pb-related deficit was found for tapping and pattern recognition with respect to PbB but not PbT No such associations could be established for VEP-latencies. These results are compatible with the hypothesis that subtle neurobehavioral dysfunction in children may be associated with very low PbB. (C) 1994 Intox Press, Inc.