Concurrent assessment on blood lead in young children and toy lead in Shanghai

Abstract Since toys are the potential sources of lead contamination for young children, we aim to compare blood lead levels (BLLs) of young children and lead-levels in toys played by the children. A total of 2249 children under 7 years old were investigated using stratified cluster sampling in 6 districts of Shanghai, their parents completed questionnaires and children’s whole blood was collected, and then BLLs were measured using tungsten atomizer absorption spectrophotometer. At the same time, 294 toys from the 6 supermarkets/ toy-stores located in the surrounding 5 districts were collected using stratified cluster sampling and lead levels in toys were measured by a portable X-ray Fluorescence instrument. The geometric mean of the BLLs was 2.02 μg/dL. After adjusting for related confounders, playing with plastic toys is a significant risk factor (β=0.067, P =0.019) for BLL-increment. Plastic toys accounted for the highest proportion (156/294, 53.06%) among the studied toys and had the highest average lead level (39.13 ppm). In the 3 districts where children’s BLLs and toys’ lead levels were both measured, the districts with higher toy lead levels had higher children’s BLLs (the average toy lead levels in Pudong-suburban vs. Xuhui vs. Yangpu supermarkets/ toy-stores: 24.62 vs. 0 vs. 15.43 ppm, P<0.01; the medians of BLLs in Pudong-suburban vs. Xuhui vs. Yangpu children: 2.07 vs. 1.55 vs. 1.50 μg/dL, P<0.001). Lead levels in toys may be associated with the BLLs of young children, and lead contamination in plastic toys need cautions for preventing young children from potential lead exposure.