Surveying mercury levels in hair, blood and urine of under 7-year old children from a coastal city in China.

Aim: The average mercury load in children under 7-years old was determined in a populated but not overly industrial coastal area in China.
Methods: 395 blood samples, 1072 urine samples, and 581 hair samples were collected from 1076 children, aged 0 to 6 years, from eight representative communities of Xiamen, China. Mercury levels in the samples were surveyed.
Results: The 95% upper limits of mercury in blood, urine, and hair for the children were 2.30, 1.50 and 2100.00 μg/kg, respectively. Levels tended to increase with age. Correlation analyses showed that mercury levels in blood and urine correlated with those in hair (n = 132), r = 0.49, p < 0.0001 and r = 0.20, p = 0.0008; however, blood mercury levels did not correlate with urine levels (n = 284), r = 0.07, p = 0.35.
Conclusions: Surveying the average mercury load in children 0 to 6 years, and the 95% upper limit value of mercury in their blood, urine, and hair should help guide risk assessment and health management for children.