title: Neurobehavioral effects of exposure to organophosphates and pyrethroid pesticides among Thai children.
abstract: The use of pesticides for crop production has grown rapidly in Thailand during the last decade, resulting in significantly greater potential for exposure among children living on farms. Although some previous studies assessed exposures to pesticides in this population, no studies have been conducted to evaluate corresponding health effects. Twenty-four children from a rice farming community (exposed) and 29 from an aquaculture (shrimp) community (control) completed the study. Participants completed a neurobehavioral test battery three times at 6 month intervals: Session I: preliminary orientation; Session II: high pesticide use season; Session III: low pesticide-use season. Only sessions II and III were used in the analyses. High and low pesticide use seasons were determined by pesticide use on rice farms. Urinary metabolites of organophosphates (OPs) and pyrethroids (PYR) were analyzed from first morning void samples collected the day of neurobehavioral testing. Rice farm participants had significantly higher concentrations of dialkylphosphates (DAPs) (common metabolites of OPs) and TCPy (a specific metabolite of chlorpyrifos) than aquaculture farm children during both seasons. But, TCPy was significantly higher during the low rather than the high pesticide use season for both participant groups. Rice farm children had significantly higher DCCA, a metabolite of PYR, than aquaculture participants only during the high exposure season. Otherwise, no significant differences in PYR metabolites were noted between the participant groups or seasons. No significant adverse neurobehavioral effects were observed between participant groups during either the high or low pesticide use season. After controlling for differences in age and the Home Observation for Measurement of the Environment (HOME) scores, DAPs, TCPy, and PYR were not significant predictors of adverse neurobehavioral performance during either season. Increasing DAP and PYR metabolites predicted some relatively small improvement in latency of response. However, due to the small sample size and inability to characterize chronic exposure, any significant differences observed should be regarded with caution. Moreover although not statistically significant, confidence intervals suggest that small to moderate adverse effects of pesticide exposure cannot be ruled out for some indicators of neurobehavioral performance.
authors.affiliation: Environmental and Occupational Health Sciences Institute, Rutgers University, 170 Frelinghuysen Road, Piscataway, NJ 08854, USA. Electronic address: nfiedler@eohsi.rutgers.edu.
authors.forename: Nancy
authors.initials: N
authors.lastname: Fiedler
authors.affiliation: College of Public Health Sciences Chulalongkorn University, Institute Building 2-3, Soi Chulalongkorn 62, Phyathai Rd., Pathumwan, Bangkok 10330, Thailand. Electronic address: r_juthasiri@yahoo.com.
authors.forename: Juthasiri
authors.initials: J
authors.lastname: Rohitrattana
authors.affiliation: College of Public Health Sciences Chulalongkorn University, Institute Building 2-3, Soi Chulalongkorn 62, Phyathai Rd., Pathumwan, Bangkok 10330, Thailand; Thai Fogarty ITREOH Center, Chulalongkorn University, Bangkok, Thailand. Electronic address: Wattasit.s@chula.ac.th.
authors.forename: Wattasit
authors.initials: W
authors.lastname: Siriwong
authors.affiliation: Faculty of Psychology, Chulalongkorn University, 7th Fl. Borommaratchachonnanisrisattapat Bldg., Rama 1 Rd., Pathumwan, Bangkok 10330, Thailand. Electronic address: cpanrapee@yahoo.com.
authors.forename: Panrapee
authors.initials: P
authors.lastname: Suttiwan
authors.affiliation: Environmental and Occupational Health Sciences Institute, Rutgers University, 170 Frelinghuysen Road, Piscataway, NJ 08854, USA. Electronic address: ohmanpa@sph.rutgers.edu.
authors.forename: Pam
authors.initials: P
authors.lastname: Ohman Strickland
authors.affiliation: Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Claudia Nance Rollins Bldg., Room 2007, Atlanta, GA 30322, USA. Electronic address: bryan@emory.edu.
authors.forename: P Barry
authors.initials: PB
authors.lastname: Ryan
authors.affiliation: Department of Occupational and Environmental Health - CPHB, The University of Iowa, Suite 300, 145 N. Riverside Dr., Iowa City, IA 52242, USA; Center for Research on Occupational and Environmental Health, Oregon Health and Science University, 3181 SW Sam Jackson Park Road - L606, Portland, OR 97239, USA. Electronic address: diane-rohlman@uiowa.edu.
authors.forename: Diane S
authors.initials: DS
authors.lastname: Rohlman
authors.affiliation: Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Claudia Nance Rollins Bldg., Room 2007, Atlanta, GA 30322, USA. Electronic address: ppanuwe@emory.edu.
authors.forename: Parinya
authors.initials: P
authors.lastname: Panuwet
authors.affiliation: Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Claudia Nance Rollins Bldg., Room 2007, Atlanta, GA 30322, USA. Electronic address: dbbarr@emory.edu.
authors.forename: Dana Boyd
authors.initials: DB
authors.lastname: Barr
authors.affiliation: Environmental and Occupational Health Sciences Institute, Rutgers University, 170 Frelinghuysen Road, Piscataway, NJ 08854, USA; Thai Fogarty ITREOH Center, Chulalongkorn University, Bangkok, Thailand; School of Environmental and Biological Sciences, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA. Electronic address: robson@aesop.rutgers.edu.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Robson
mesh_terms: D000367:Age Factors; D000383:Agriculture; D001288:Attention / Q000187:drug effects; D015415:Biomarkers / Q000652:urine; D001711:Biotransformation; D016022:Case-Control Studies; D002648:Child; D002652:Child Behavior / Q000187:drug effects*; D003071:Cognition / Q000187:drug effects; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007306:Insecticides / Q000009:adverse effects* / Q000652:urine; D008297:Male; D008568:Memory / Q000187:drug effects; D009420:Nervous System / Q000187:drug effects* / Q000503:physiopathology; D009483:Neuropsychological Tests; D020258:Neurotoxicity Syndromes / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology / Q000652:urine; D062025:Organophosphate Poisoning / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology / Q000652:urine; D063065:Organophosphonates / Q000009:adverse effects* / Q000652:urine; D012275:Oryza; D011722:Pyrethrins / Q000009:adverse effects* / Q000652:urine; D018570:Risk Assessment; D012307:Risk Factors; D012423:Rural Health; D012621:Seasons; D013785:Thailand; D013997:Time Factors
chemical_list: D015415:Biomarkers; D007306:Insecticides; D063065:Organophosphonates; D011722:Pyrethrins
keywords: Children; Neurobehavior; Organophosphates; Pesticides; Pyrethroids; Thailand