Prenatal Exposure to Organophosphate Pesticides and Neurobehavioral Development of Neonates: A Birth Cohort Study in Shenyang, China

Ying Zhang,Li Zhang,Yingzi Gu,Duohong Liang,Ying Tian,Xinzhu Shi,Fengzhi Wang,Lixin Chen,Song Han,Wei Liu,Aditya Bhushan Pant

doi:10.1371/journal.pone.0088491

Abstract

BackgroundA large amount of organophosphate pesticides (OPs) are used in agriculture in China every year, contributing to exposure of OPs through dietary consumption among the general population. However, the level of exposure to OPs in China is still uncertain.ObjectiveTo investigate the effect of the exposure to OPs on the neonatal neurodevelopment during pregnancy in Shenyang, China.Methods249 pregnant women enrolled in the Central Hospital Affiliated to Shenyang Medical College from February 2011 to August 2012. A cohort of the mothers and their neonates participated in the study and information on each subject was obtained by questionnaire. Dialkyl phosphate (DAP) metabolites were detected in the urine of mothers during pregnancy to evaluate the exposure level to OPs. Neonate neurobehavioral developmental levels were assessed according to the standards of the Neonatal Behavioral Neurological Assessment (NBNA). Multiple linear regressions were utilized to analyze the association between pregnancy exposure to OPs and neonatal neurobehavioral development.ResultsThe geometric means (GM) of urinary metabolites for dimethyl phosphate (DMP), dimethyl thiophosphate (DMTP), diethyl phosphate (DEP), and diethyl thiophosphate (DETP) in pregnant women were 18.03, 8.53, 7.14, and 5.64 µg/L, respectively. Results from multiple linear regressions showed that prenatal OP exposure was one of the most important factors affecting NBNA scores. Prenatal total DAP concentrations were inversely associated with scores on the NBNA scales.?Additionally, a 10-fold increase in DAP concentrations was associated with a decrease of 1.78 regarding the Summary NBNA (95% CI, −2.12 to −1.45). And there was an estimated 2.11-point difference in summary NBNA scores between neonates in the highest quintile of prenatal OP exposure and the lowest quintile group.ConclusionThe high exposure of pregnant women to OPs in Shenyang, China was the predominant risk factor for neonatal neurobehavioral development.

Highlights

As one of the largest developing agriculture countries, China must manage to maintain and increase crop yields from year to year
As a result of the heavy use of organophosphate pesticides (OPs) in agriculture, more than 10 percent of fruits, vegetables, and cereal grains grown in China contain pesticide residues exceeding the national safety standard [3,4]
Besides raw foods treated by OPs, contaminated drinking water, dust, and spray drift commonly contribute to OPs exposure among the general population [9]

Summary

Introduction

As one of the largest developing agriculture countries, China must manage to maintain and increase crop yields from year to year. Along with the wide-spread use of highly toxic organophosphate pesticides (OPs) (with potent toxicity to insects, relatively low costs and the decreased likelihood for pest resistance [2] ), OPs account for more than 1/3 of all insecticide use in China. Some highly toxic OPs such as parathion and methamidophos, which have been banned in China since 2007, have still been detected in vegetable samples through routine monitoring by the Ministry of Agriculture [8]. To our knowledge, it is uncertain to know the exposure level to OPs and the effect on the health of the general population in China. A large amount of organophosphate pesticides (OPs) are used in agriculture in China every year, contributing to exposure of OPs through dietary consumption among the general population. The level of exposure to OPs in China is still uncertain

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Results

Discussion

Conclusion