title: Occupational exposure to particulate matter and endotoxin for California dairy workers.
abstract: Occupational exposure of dairy workers to particulate matter (PM) and endotoxin has been considered by some to be of potential concern. This paper reports personal exposure concentrations of PM (μg/m3) and endotoxin (EU/m3) for 226 workers from 13 California dairies. Arithmetic mean personal concentrations for PM2.5, inhalable PM and endotoxin were 48 μg/m3 (N = 222), 987 μg/m3 (N = 225) and 453 EU/m3 (N = 225), respectively. Using mixed effects models, time spent re-bedding of freestall barns versus any other job conducted on a dairy led to the highest exposure for PM2.5, inhalable PM, and endotoxin. Personal exposure concentrations were found to be greater than those reported for ambient area based concentrations at the same dairies. A pseudo R-square approach revealed that one area based measure combined with time spent performing tasks explained a significant portion of variation in personal exposure concentrations.
authors.affiliation: Department of Public Health Sciences and Center for Health and the Environment, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Johnny
authors.initials: J
authors.lastname: Garcia
authors.forename: Deborah H
authors.initials: DH
authors.lastname: Bennett
authors.forename: Daniel
authors.initials: D
authors.lastname: Tancredi
authors.forename: Marc B
authors.initials: MB
authors.lastname: Schenker
authors.forename: Diane
authors.initials: D
authors.lastname: Mitchell
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Reynolds
authors.forename: Frank M
authors.initials: FM
authors.lastname: Mitloehner
mesh_terms: D000818:Animals; D002140:California; D002417:Cattle; D003430:Cross-Sectional Studies; D003612:Dairying; D004731:Endotoxins / Q000032:analysis*; D004784:Environmental Monitoring; D006801:Humans; D016273:Occupational Exposure / Q000032:analysis*; D052638:Particulate Matter / Q000032:analysis*; D012044:Regression Analysis
chemical_list: D004731:Endotoxins; D052638:Particulate Matter