Dietary intake of mercury by children and adults in Jinhu area of China

Dietary intakes of mercury by children and adults in Jinhu area of China were determined using a duplicate diet approach. A total of 176 duplicate diet portions were collected from 60 individuals in November and December of 2007. Mercury levels in duplicate samples were measured by atomic fluorescence spectrometry. The daily mercury intakes (median and range) from consumption days without fish or shellfish for children and adults were 0.13 (0.05–0.78) μg(kgbw)−1 day−1 and 0.07 (0.04–0.18) μg(kgbw)−1 day−1, respectively, which were significantly lower than those from consumption days with fish or shellfish for both children and adults whose daily intakes (median and range) were 0.16 (0.11–0.84) μg(kgbw)−1 day−1 and 0.09 (0.05–0.46) μg(kgbw)−1 day−1, respectively. The exposure level of children was significantly higher than that of adults. The 50th and 99th percentile of the usual mercury intake from all consumption days for children were 0.14 and 0.22 μg(kgbw)−1 day−1 and for adults were 0.09 and 0.14 μg(kgbw)−1 day−1, where the between-person variance in dietary mercury intake for children and adults were 0.038 and 0.036, respectively. Comparing with the provisional tolerable weekly intake (PTWI) divided into daily intake (PTDI) of 0.57 μg(kgbw)−1 day−1, it is concluded that the average daily intakes and the usual intakes to mercury can be considered safe for both children and adults in Jinhu area by the duplicate diet study. But the maximum daily intakes for children exceeding the PTDI deserve a close attention.