The Impact of Prenatal Organophosphate Pesticide Exposures on Thai Infant Neurodevelopment.

Pornpimol Kongtip,Noppanun Nankongnab,Supha Sangprasert,Aree Thongsuksai,Benyachalee Techasaensiri,Susan Woskie,Anu Surach,Prayoon Srikumpol,Akkarat Phamonphon,Jane Adams

doi:10.3390/ijerph14060570

Abstract

A birth cohort was begun to investigate the levels and sources of pesticide exposure in pregnant women living in Thailand, and to examine the effects of pesticide exposure on infant neurodevelopment at five months of age. Subjects were interviewed using questionnaires regarding their demographic characteristics, educational background, and work and home activities related to pesticide exposures. Spot urine samples were collected at 28 weeks gestation and analyzed by gas chromatography-mass spectrometry to determine maternal metabolite levels of organophosphate pesticides including dimethyl phosphate (DMP); total DEP (diethyl phosphate (DEP), diethyl thiophosphate (DETP), and diethyl dithiophosphate (DEDTP), and total DAP (the sum of all metabolite levels). At five months of age, infant development was evaluated using the Bayley Scales of Infant and Toddler Development-III (Bayley-III). Higher total DEP and total DAP metabolite levels from the mother at 28 weeks’ gestation were significantly associated with reduced motor composite scores on the Bayley-III at five months of age. The total DEP levels were also significantly associated with reduced cognitive composite scores. Prenatal concentrations of maternal urinary metabolites were associated with infant cognitive and motor development. The results of several studies now suggest the need for public health intervention to reduce prenatal pesticide exposures from both agricultural and domestic use.

Highlights

Thailand is an agricultural nation, in which approximately 38% of the population engages in agricultural work [1] and in 2014, 134,377 tons of pesticides were imported for use
Our results indicated a significant relationship between prenatal total DEP levels and cognitive and motor performance, and a significant relationship between prenatal total dialkyl phosphate (DAP) levels and composite motor scores
Higher total DEP and total DAP metabolite levels from the mother at week 28 of gestation were significantly associated with reduced motor composite scores on the Bayley-III at five months of age

Summary

Introduction

Thailand is an agricultural nation, in which approximately 38% of the population engages in agricultural work [1] and in 2014, 134,377 tons of pesticides were imported for use. In 2012, pesticide poisonings in Thailand were reported at a rate of 12.37 per 100,000 population. Median non-creatinine-adjusted urinary dialkyl phosphate (DAP) metabolite levels of 160.9 and 190.8 nmol/L were found at high levels at 28 weeks of pregnancy and at delivery period, respectively [4]. These levels are higher than those reported in pregnant women who live in an agricultural community at 106.8 nmol/L for DAP over 26 weeks according to the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS)

Methods

Results

Discussion

Conclusion