title: Merging models and biomonitoring data to characterize sources and pathways of human exposure to organophosphorus pesticides in the Salinas Valley of California.
abstract: We characterize cumulative intakes of organophosphorus (OP) pesticides in an agricultural region of California by drawing on human biomonitoring data, California pesticide use reporting (PUR) data, and limited environmental samples together with outputs from the CalTOX multimedia, multipathway, source-to-dose model. The study population is the CHAMACOS cohort of almost 600 pregnant Latina women in the Salinas Valley region. We use model estimates of OP intake and urinary dialkylphosphate (DAP) metabolite excretion to develop premises about relative contributions from different exposure sources and pathways. We evaluate these premises by comparing the magnitude and variation of DAPs in the CHAMACOS cohort with those of the whole U.S. population using data from the National Health and Nutrition Examination Survey (NHANES). This comparison supports the premise that diet is the common and dominant exposure pathway in both populations. Biomarker comparisons and model results support the observation that, relative to NHANES, the CHAMACOS population has a statistically significant (p < 0.001) added intake of OP pesticides with low inter-individual variability. We attribute the magnitude and small variance of this intake to residential nondietary exposures from local agricultural OP uses. These results show that mass-balance models can estimate exposures for OP pesticides within the range measured by biological monitoring.
authors.affiliation: Lawrence Berkeley National Laboratory, Berkeley, California, Center for Children's Environmental Health Research, School of Public Health, University of California, Berkeley, California, USA. temckone@LBL.gov
authors.forename: Thomas E
authors.initials: TE
authors.lastname: McKone
authors.forename: Rosemary
authors.initials: R
authors.lastname: Castorina
authors.forename: Martha E
authors.initials: ME
authors.lastname: Harnly
authors.forename: Yu
authors.initials: Y
authors.lastname: Kuwabara
authors.forename: Brenda
authors.initials: B
authors.lastname: Eskenazi
authors.forename: Asa
authors.initials: A
authors.lastname: Bradman
mesh_terms: D000328:Adult; D016902:Air Pollution, Indoor / Q000032:analysis; D002140:California; D004032:Diet; D004391:Dust / Q000032:analysis; D004781:Environmental Exposure / Q000032:analysis*; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis* / Q000652:urine; D005260:Female; D005506:Food Contamination; D006801:Humans; D008962:Models, Theoretical; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000652:urine; D010573:Pesticide Residues / Q000032:analysis / Q000652:urine; D010575:Pesticides / Q000032:analysis* / Q000652:urine; D011247:Pregnancy
chemical_list: D004391:Dust; D004785:Environmental Pollutants; D009943:Organophosphorus Compounds; D010573:Pesticide Residues; D010575:Pesticides