Hair mercury level and its influencing factors among children of 0-35 months

Objective To investigate the status and influencing factors of mercury exposure among community children aged 0-35 months in Xiamen city.Methods A total of 1 041 healthy children aged 0-35 months were selected from 10 communities with stratified cluster sampling and surveyed with Children Society and Family Questionnaire and the hair samples of the children were collected simultaneously from April to June of 2010.Results The average hair mercury was 0.985 μg/g,with a geometric mean of 0.724 μg/g.There was 31.70% of the children with hair mercury level over the reference dose(RfD) of 1 μg/g.The hair mercury level was the highest in the children of islet communities(1.559 μg/g,53.26% higher than that of RfD),while,the lowest one was in the children from remote rural area(0.684 μg/g,14.56% higher than that of RfD),with significant difference between the two groups(F=6.70,P=0.01).Fish and shellfish consumption had a positive correlation with the hair mercury level(F=12.68,P<0.01;F=3.596,P=0.009).The children from the families with hair tint use had a higher hair mercury level than the chidren from families without hair tint use(β=6.186,t=3.165,P=0.002).The hair mercury levels were positively correlated with the age(t=2.220,P=0.027).However,hair mercury levels showed no correlation with gender and sleep status of the children.Conclusion The hair mercury level for 0-35 months old children in Xiamen city was close to the hazardous level.The hair mercury level was higher in the children from islets than those from the remote rural area.Fish and shellfish consumption and hair tint use were the main factors of mercury exposure.Older children had higher mercury level than younger children.