title: Determinants of organophosphorus pesticide urinary metabolite levels in young children living in an agricultural community.
abstract: Organophosphorus (OP) pesticides are used in agriculture and several are registered for home use. As young children age they may experience different pesticide exposures due to varying diet, behavior, and other factors. We measured six OP dialkylphosphate (DAP) metabolites (three dimethyl alkylphosphates (DMAP) and three diethyl alkylphosphates (DEAP)) in urine samples collected from ~400 children living in an agricultural community when they were 6, 12, and 24 months old. We examined bivariate associations between DAP metabolite levels and determinants such as age, diet, season, and parent occupation. To evaluate independent impacts, we then used generalized linear mixed multivariable models including interaction terms with age. The final models indicated that DMAP metabolite levels increased with age. DMAP levels were also positively associated with daily servings of produce at 6- and 24-months. Among the 6-month olds, DMAP metabolite levels were higher when samples were collected during the summer/spring versus the winter/fall months. Among the 12-month olds, DMAP and DEAP metabolites were higher when children lived ≤ 60 meters from an agricultural field. Among the 24-month-olds, DEAP metabolite levels were higher during the summer/spring months. Our findings suggest that there are multiple determinants of OP pesticide exposures, notably dietary intake and temporal and spatial proximity to agricultural use. The impact of these determinants varied by age and class of DAP metabolite.
authors.affiliation: Center for Environmental Research and Children's Health, School of Public Health, University of California at Berkeley, 1995 University Avenue, Berkeley, CA 94720, USA. abradman@berkeley.edu
authors.forename: Asa
authors.initials: A
authors.lastname: Bradman
authors.forename: Rosemary
authors.initials: R
authors.lastname: Castorina
authors.forename: Dana Boyd
authors.initials: DB
authors.lastname: Barr
authors.forename: Jonathan
authors.initials: J
authors.lastname: Chevrier
authors.forename: Martha E
authors.initials: ME
authors.lastname: Harnly
authors.forename: Ellen A
authors.initials: EA
authors.lastname: Eisen
authors.forename: Thomas E
authors.initials: TE
authors.lastname: McKone
authors.forename: Kim
authors.initials: K
authors.lastname: Harley
authors.forename: Nina
authors.initials: N
authors.lastname: Holland
authors.forename: Brenda
authors.initials: B
authors.lastname: Eskenazi
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000383:Agriculture; D002652:Child Behavior; D002675:Child, Preschool; D004032:Diet / Q000706:statistics & numerical data; D004781:Environmental Exposure / Q000032:analysis*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010755:Organophosphates / Q000652:urine; D009943:Organophosphorus Compounds / Q000652:urine*; D009946:Organothiophosphorus Compounds / Q000652:urine; D010575:Pesticides / Q000652:urine*; D011247:Pregnancy; D012737:Sex Factors; D055815:Young Adult
chemical_list: D010755:Organophosphates; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D010575:Pesticides; C034789:diethyl phosphate; C007477:dimethyl phosphate