The relationship between arsenic concentration and arsenic methylation profiles on early neurodevelopment effects in very low birth weights preterm infants

• Main Authors: Guang-Lin Kuo, 郭洸霖
• Other Authors: 簡伶朱
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/3cm2jv

碩士 === 臺北醫學大學 === 公共衛生學系暨研究所 === 102 === Arsenic has been classified as a “group 1 carcinogen” by the International Agency for Research on Cancer and it could affect the nervous system. Few researches have shown that children exposed to arsenic could affect to their growth and neurodevelopment. The neurological prognosis of the very low birth weight (VLBW) preterm infants at first two years will influence their neurodevelopment during school-age and adolescent. Thus, children exposure to environmental contaminants should be paying more attention in the postnatal period. The purpose of this study was to investigate the relationship between urine arsenic concentrations, arsenic methylation capability and toenail accummulated arsenic concentration on cognitive, language and motor developments. The participants in our study were recruited from October 2010 to April 2012. The urine and toenail samples were collected as a biomarker to assess arsenic exposure. The Bayley scales of infant development III was used to evaluate the cognitive, language, and motor development at 6, 12, 24 months of corrected age. The level of arsenic speciation in urine was analyzed using HPLC-HG-AAS. The level of arsenic in toenails was analyzed using ICP-MS after water bath digested. Total of 60 eligible VLBW preterm infants were enrolled. The average concentration of total arsenic was 28.6 μg/g creatinine, and inorganic arsenic was 1.01 μg/L in urine. Child urine contained on average 3% inorganic arsenic, 2% monomethylarsonic acid, and 95% dimethylarsinic acid. The primary arsenic methylation index and secondary arsenic methylation index was 1.29 and 136, respectively. The average cumulative concentration of arsenic in toenails was 225 ng/g. Urinary arsenic concentrations, arsenic methylation capability index, and toenail arsenic concentration was not significantly correlated with growth development at 6 months, 1 year, and 2 yearsold. We also found that postnatanl arsenic exposure did not show significant influence on neurological development. The gestation, weight, and head circumference at birth were significantly correlated with the neurological development at 6 months, 1 year, and 2 years old. Our study results suggested that VLBW preterm children have a low-level arsenic exposure. We recommend that further study may simultaneously analyze multiple environmental contaminants such as lead, cadmium, mercury, and PCBs that may have adverse effects on neurodevelopment. To better understand the influence of arsenic exposure on neurodevelopment.