Nephrotoxicity, neurotoxicity, and mercury exposure among children with and without dental amalgam fillings.
OBJECTIVE
A scientific review panel for the US Food and Drug Administration (FDA) recently identified the need for more data on the health risk of mercury exposure from dental amalgam among susceptible populations. We evaluated impacts of low-level mercury exposure on renal function and neurobehavioral and neuropsychological performance among children.


METHODS
Dental histories for 403 children aged 7-11 years in five schools from Xuhui, Shanghai were checked by dentists. Of them, 198 with confirmed amalgam fillings were recruited (exposure group). Reference children (N=205) were those who never had dental amalgam treatment. In May 2004, each child provided a urine sample for measurements of total mercury, N-acetyl-beta-D-glucosaminidase activity, microalbumin, and creatinine (Cr). The Child Behavior Checklist, Eysenck Personality Questionnaire, and an intelligence screening test were administered.


RESULTS
The geometric mean urinary mercury concentration was 1.6 microg/g Cr for children with and 1.4 microg/g Cr for children without amalgam fillings. No differences were found between children with and without fillings for either renal function biomarker, or on neurobehavioral, neuropsychological, or intelligence tests.


CONCLUSIONS
Although urinary mercury concentration was slightly elevated among children with amalgam fillings, we found no evidence of adverse effects on the outcomes evaluated. These results agree with those from recent trials in developed countries.
Ye
Xibiao
X
Department of Preventive Medicine, School of Public Health, Fudan University, PO Box 248, 138 Yixueyuan Road, Shanghai 20032, China. yex2@niehs.nih.gov
Qian
Haojun
H
Xu
Peicheng
P
Zhu
Lin
L
Longnecker
Matthew P
MP
Fu
Hua
H
D000118:Acetylglucosaminidase / Q000652:urine; D000419:Albuminuria; D015415:Biomarkers / Q000652:urine; D002648:Child; D002652:Child Behavior / Q000187:drug effects; D002681:China; D003404:Creatinine / Q000652:urine; D003723:Dental Amalgam / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007360:Intelligence / Q000187:drug effects; D007668:Kidney / Q000187:drug effects*; D008297:Male; D008628:Mercury / Q000009:adverse effects* / Q000652:urine; D020258:Neurotoxicity Syndromes / Q000209:etiology* / Q000652:urine; D010551:Personality / Q000187:drug effects
D015415:Biomarkers; D003723:Dental Amalgam; D003404:Creatinine; D000118:Acetylglucosaminidase; D008628:Mercury