Human biomonitoring of cadmium and lead exposure of child–mother pairs from Germany living in the vicinity of industrial sources (Hot Spot Study NRW)

Cadmium (Cd) and lead (Pb) exposure of children and their mothers living in the vicinity of industrial sources (metal refining) was assessed by a cross-sectional study performed in 2000. Study areas were the highly industrialized city of Duisburg and a rural area of North Rhine Westphalia, Germany. Exposure to ambient air concentrations of Cd and Pb was calculated from a Lagrange dispersion model using data sets from ambient air quality measurements. Cd in blood and urine and Pb in blood were measured by AAS. Mean age (years) was 6.4 (range 5.5–7.7) for children ( n = 238 ) and 36 (range 23–48) for mothers ( n = 213 ). A total of 49% of the children were males. Factors suspected to influence metal levels in blood or urine were obtained by questionnaire. Individual ambient Cd and Pb levels according to the home address ranged from 0.5 ng/m3 (Cd) and 0.03 μg/m3 (Pb) (rural area) up to 31.2 ng/m3 (Cd) and 0.73 μg/m3 (Pb) (industrialized area). Cd levels (geometric mean) in blood (0.13 and 0.10 μg/L) and urine (both areas 0.09 μg/L) of children did not differ between the two areas. Cd levels in blood and urine of mothers from the industrialized area were higher (blood 0.39 μg/L, urine 0.28 μg/L) than in those from the rural area (blood 0.25 μg/L, urine 0.25 μg/L). Pb levels in the blood of children from the industrialized area were higher (31 μg/L) than in those from the rural area (21 μg/L). Pb levels in the blood of mothers did not differ between the two areas (both 24 μg/L). Pb levels in blood showed a significant association between child and mother ( n = 192 ; r = 0.26 , p < 0.001 ). This did not apply for Cd in blood or urine. Regression analysis clearly revealed that Pb levels in ambient air were associated with Pb in the blood of children. Minor associations were also found between Cd in air and Cd in the blood of mothers and between Cd in air and urine of mothers.