title: Associations of maternal organophosphate pesticide exposure and PON1 activity with birth outcomes in SAWASDEE birth cohort, Thailand.
abstract: Prenatal organophosphate (OP) pesticide exposure has been reported to be associated with adverse birth outcomes and neurodevelopment. However, the mechanisms of toxicity of OP pesticides on human fetal development have not yet been elucidated. Our pilot study birth cohort, the Study of Asian Women and Offspring's Development and Environmental Exposures (SAWASDEE cohort) aimed to evaluate environmental chemical exposures and their relation to birth outcomes and infant neurodevelopment in 52 pregnant farmworkers in Fang district, Chiang Mai province, Thailand. A large array of data was collected multiple times during pregnancy including approximately monthly urine samples for evaluation of pesticide exposure, three blood samples for pesticide-related enzyme measurements and questionnaire data. This study investigated the changes in maternal acetylcholinesterase (AChE) and paraoxonase 1 (PON1) activities and their relation to urinary diakylphosphates (DAPs), class-related metabolites of OP pesticides, during pregnancy. Maternal AChE, butyrylcholinesterase (BChE) and PON1 activities were measured three times during pregnancy and urinary DAP concentrations were measured, on average, 8 times from enrollment during pregnancy until delivery. Among the individuals in the group with low maternal PON1 activity (n=23), newborn head circumference was negatively correlated with log10 maternal ∑DEAP and ∑DAP at enrollment (gestational age=12±3 weeks; β=-1.0 cm, p=0.03 and β=-1.8 cm, p<0.01, respectively) and at 32 weeks pregnancy (β=-1.1cm, p=0.04 and β=-2.6 cm, p=0.01, respectively). Furthermore, among these mothers, newborn birthweight was also negatively associated with log10 maternal ∑DEAP and ∑DAP at enrollment (β=-219.7 g, p=0.05 and β=-371.3g, p=0.02, respectively). Associations between maternal DAP levels and newborn outcomes were not observed in the group of participants with high maternal PON1 activity. Our results support previous findings from US birth cohort studies. This is the first study to report the associations between prenatal OP pesticide exposure and birth outcomes in Thailand.
authors.affiliation: Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand; Environmental Science Program, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Warangkana
authors.initials: W
authors.lastname: Naksen
authors.affiliation: Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand. Electronic address: tprapamontol@gmail.com.
authors.forename: Tippawan
authors.initials: T
authors.lastname: Prapamontol
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Ampica
authors.initials: A
authors.lastname: Mangklabruks
authors.affiliation: Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Somporn
authors.initials: S
authors.lastname: Chantara
authors.affiliation: Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Prasak
authors.initials: P
authors.lastname: Thavornyutikarn
authors.affiliation: Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand.
authors.forename: Niphan
authors.initials: N
authors.lastname: Srinual
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
authors.forename: Parinya
authors.initials: P
authors.lastname: Panuwet
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
authors.forename: P Barry
authors.initials: PB
authors.lastname: Ryan
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Riederer
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
authors.forename: Dana Boyd
authors.initials: DB
authors.lastname: Barr
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood; D000293:Adolescent; D000328:Adult; D000383:Agriculture; D043303:Aryldialkylphosphatase / Q000097:blood*; D001724:Birth Weight / Q000187:drug effects*; D002091:Butyrylcholinesterase / Q000097:blood; D015331:Cohort Studies; D005260:Female; D005312:Fetal Blood / Q000201:enzymology; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D018811:Maternal Exposure / Q000009:adverse effects*; D009943:Organophosphorus Compounds / Q000633:toxicity* / Q000652:urine; D010575:Pesticides / Q000633:toxicity* / Q000652:urine; D011247:Pregnancy; D013785:Thailand; D055815:Young Adult
chemical_list: D009943:Organophosphorus Compounds; D010575:Pesticides; D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human
keywords: Birth cohort; Birth outcomes; Exposure assessment.; Organophosphate pesticides; Paraoxonase 1 (PON1)