title: Correlating agricultural use of organophosphates with outdoor air concentrations: a particular concern for children.
abstract: For the organophosphate pesticide chlorpyrifos, median inhalation noncancer, acute children's exposures in agricultural communities are elevated above reference doses; for diazinon, similar exposures are nearly elevated. We used multivariate linear regression analysis to examine the temporal and spatial associations between agricultural use and measured air concentrations of chlorpyrifos, chlorpyrifos oxon, diazinon, and malathion. Agricultural use within a 3-mile radius on the monitoring day and use on the 2-4 prior days were significantly associated with air concentrations (p < 0.01) for all analytes except malathion; chlorpyrifos oxon showed the strongest association (p < 0.0001). In the final models, which included weather parameters, the proportion of variance (r2, adjusted for the number of model variables) for all analytes ranged from 0.28 (p < 0.01) for malathion to 0.65 (p < 0.0001) for diazinon. Recent cellular, animal, and human evidence of toxicity, particularly in newborns, supports the public health concern indicated by initial risk estimates. Agricultural applications of organophosphates and their oxon products may have substantial volatization and off-field movement and are a probable source of exposures of public health concern.
authors.affiliation: California Department of Health Services, Oakland, CA 94612, USA. mharnly@dhs.ca.gov
authors.forename: Martha
authors.initials: M
authors.lastname: Harnly
authors.forename: Robert
authors.initials: R
authors.lastname: McLaughlin
authors.forename: Asa
authors.initials: A
authors.lastname: Bradman
authors.forename: Meredith
authors.initials: M
authors.lastname: Anderson
authors.forename: Robert
authors.initials: R
authors.lastname: Gunier
mesh_terms: D000383:Agriculture; D000393:Air Pollutants / Q000032:analysis*; D002140:California; D002648:Child; D004784:Environmental Monitoring; D006801:Humans; D016014:Linear Models; D009946:Organothiophosphorus Compounds / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D011891:Rain; D012044:Regression Analysis; D013696:Temperature; D014919:Wind
chemical_list: D000393:Air Pollutants; D009946:Organothiophosphorus Compounds; D010575:Pesticides