The neurological effects of prenatal and postnatal mercury/methylmercury exposure on three-year-old children in Taiwan.
This study attempts to elucidate the relationship between neurological effects and mercury/methylmercury concentrations in various biomarkers, including meconium, hair, fingernail, and toenail. Eight-three mother-infant pairs were recruited between August 2008 and December 2009, and follow-up examinations on these children were completed after three years. The Bayley Scales of Infant and Toddler Development (Bayley-III) for evaluating the cognitive, language, and motor development of three-year-old children were calculated and validated. The geometric mean of the total mercury concentration in meconium was 89.6 ng g(-1). The methylmercury concentrations in hair, fingernail, and toenail samples were 1.96, 0.64, and 0.55 μg g(-1), respectively. Seventy percent of children had hair methylmercury concentrations exceeding the U.S. environmental protection agency (EPA) reference of 1 μg g(-1). A significantly positive correlation was obtained between methylmercury levels in hair, fingernail, and toenail. These methylmercury levels were also significantly positively correlated with the children's fish intake and negatively correlated with a Bayley-III scale score of expressive language. The prenatal mercury exposure, however, did not show significant influence on neurological development. High fish consumption appears to be a critical risk factor for methylmercury levels in children and may cause a lower expressive language score.
Graduate Institute of Environmental Engineering, National Taiwan University, Taiwan.
Hsing-Cheng
HC
Hsi
Department of Pediatrics, Taipei Mackay Memorial Hospital, Taipei, Taiwan; Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan.
Chuen-Bin
CB
Jiang
School of Public Health, Taipei Medical University, Taiwan.
Tzu-Hsuan
TH
Yang
School of Public Health, Taipei Medical University, Taiwan. Electronic address: lcchien@tmu.edu.tw.
Ling-Chu
LC
Chien
D000328:Adult; D000818:Animals; D002675:Child, Preschool; D003071:Cognition / Q000187:drug effects; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005399:Fishes; D006801:Humans; D007223:Infant; D008297:Male; D008628:Mercury / Q000378:metabolism / Q000633:toxicity*; D008767:Methylmercury Compounds / Q000378:metabolism / Q000633:toxicity*; D009483:Neuropsychological Tests; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000378:metabolism / Q000503:physiopathology*; D013624:Taiwan; D014481:United States
D008767:Methylmercury Compounds; D008628:Mercury
Children; Fish intake; Mercury; Methylmercury; Neurological effects