Predicted intake of trace elements and minerals via household drinking water by 6-year-old children from Kraków (Poland). Part 1: lead (year 2000).

A population of 232 children living in urban, peripheral and rural areas of southern Poland was included in the study. Household drinking water was collected twice a day, early in the morning and in the evening. The lead (Pb) concentration was estimated by a graphite furnace-atomic absorption spectroscopy (GF-AAS) method. The geometric mean of Pb concentration in drinking water in 2000 for evening samples was 0.68, 1.24 and 2.28 microg x l(-1) for urban, peripheral and rural areas, respectively, while for morning samples it was 1.42, 2.16 and 2.97 microg x l(-1). These areas differed significantly (p < 0.05) and odds ratio for peripheral versus urban areas was 1.6. The difference of Pb concentrations in the morning and evening water was significant (p < 0.001). The mean ratio was 1.8 and the median difference 0.8 microg x l(-1). The predicted contribution of drinking water to the Pb intake by 6-year-old children living in urban, peripheral and rural areas was 1.2, 2.0 and 5.6% of the provisional tolerable weekly intake (PTWI) respectively. For the 4.3-11.1% of children, the Pb concentration in water > 10 microg x l(-1) and in these cases the predicted Pb intake with drinking water contributed to PTWI by 22.3-30.0%. The simple test introduced in this study, the analysis of morning and evening water samples, proved that contamination of water in the plumbing is significant and common. The above parameters can be applied to routine quality control of drinking water performed in the households. The in-house water contamination should be considered as a factor in public health protection programmes with special attention to children.