Association between Organophosphate Pesticides Exposure and Children Cognitive Behavior in Northern Taiwan

• Main Authors: Meng-Ying Chiu, 邱孟瑩
• Other Authors: Mei-Lien Chen
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/x436t2

碩士 === 國立陽明大學 === 環境與職業衛生研究所 === 107 === Taiwan is located in the subtropical zone, the weather is generally hot and humid. Because of the topography and location, Taiwan employs intensive agriculture. Organophosphate pesticides (OPs) are the most heavily used pesticides and are commonly detected in general public including pregnant women and children. These compounds are proven endocrine disrupters that may affect the neural development in humans, particularly in fetus and child. Thus, the aims of this study are (1) to determine the prenatal and postnatal exposure to OPs, and (2) to examine the associations between the prenatal and postnatal OPs exposure level and neurodevelopmental effects in children at 2 years of age. In a prospective cohort of 280 mother-child pairs, urine samples of prenatal and postnatal were collected from each participant and analyzed for metabolites of OPs by using gas chromatography–mass spectrometry. Six analytes were measured including dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP), and diethyldithiophosphate (DEDTP). The Bayley Scales of Infant and Toddler Development (Bayley-III) was used to assess children's neurodevelopment outcome at 2 years old. The association between OPs exposure and Bayley-III scale score was determined by using the Mann-Whitney U test, linear regression model, and logistic regression model. In this study, urine samples of 59 mothers and 81 children were measured the concentrations of urinary organophosphate metabolites. In the 81 children, the geometric mean (GM) levels (nM) of urinary DMP, DMTP, DMDTP, DEP, DETP, DEDTP, DMs, DEs, and DAPs were 159.41, 70.46, 30.36, 1.79, 38.04, 4.94, 454.57, 71.46, and 741.40, respectively. In this study, the urinary OPs levels in children were considerably higher than other countries. In 59 pregnant women, the geometric mean (GM) levels (nM) of urinary DMP, DMTP, DMDTP, DEP, DETP, DEDTP, DMs, DEs, and DAPs were 19.34, 211.23,139.73,1.75,84.76, 66.52, 627.74, 305.24, and 985.96 respectively. In linear regression model, after adjusting for the creatinine, we observed that prenatal DMTP was negatively associated with cognitive score (β=-8.34; p-value=0.02). Also, postnatal DMDTP was negatively associated with cognitive score (β=-4.18; p-value=0.05). In logistic regression, we found postnatal DAPs concentration increasing the risk of low cognitive score (odds ratio(OR)=4.12; 95% confidence interval (CI), 1.03-16.56; p-value=0.05) and language score (OR=3.53; 95% CI, 1.01-12.35; p-value=0.05). This study indicates the significant associations between prenatal and postnatal exposure to OPs and scores of cognitive and language of Bayley-III test. It supported that OPs exposure might affect neurodevelopment outcomes of fetus and child. Due to the small sample size, the conclusion needs to be verified further.