Estimating volatile organic compound concentrations in selected microenvironments using time-activity and personal exposure data.
Sexton-K; Mongin-SJ; Adgate-JL; Pratt-GC; Ramachandran-G; Stock-TH; Morandi-MT
J Toxicol Environ Health A 2007 Jan; 70(5):465-476
Repeated measures of personal exposure to 14 volatile organic compounds (VOC) were obtained over 3 seasons for 70 healthy, nonsmoking adults living in Minneapolis-St. Paul. Matched data were also available for participants' time-activity patterns, and measured VOC concentrations outdoors in the community and indoors in residences. A novel modeling approach employing hierarchical Bayesian techniques was used to estimate VOC concentrations (posterior mode) and variability (credible intervals) in five microenvironments: (1) indoors at home; (2) indoors at work/school; (3) indoors in other locations; (4) outdoors in any location; and (5) in transit. Estimated concentrations tended to be highest in "other" indoor microenvironments (e.g., grocery stores, restaurants, shopping malls), intermediate in the indoor work/school and residential microenvironments, and lowest in the outside and in-transit microenvironments. Model estimates for all 14 VOC were reasonable approximations of measured median concentrations in the indoor residential microenvironment. The largest predicted contributor to cumulative (2-day) personal exposure for all 14 VOC was the indoor residential environment. Model-based results suggest that indoors-at-work/school and indoors-at-other-location microenvironments were the second or third largest contributors for all VOC, while the outside-in-any-location and in-transit microenvironments appeared to contribute negligibly to cumulative personal exposure. Results from a mixed-effects model indicate that being in or near a garage increased personal exposure to o-xylene, m/p-xylene, benzene, ethylbenzene, and toluene, and leaving windows and doors at home open for 6 h or more decreased personal exposure to 13 of 14 VOC, all except trichloroethylene.
Airborne-particles; Air-contamination; Biohazards; Biological-effects; Chemical-hypersensitivity; Environmental-exposure; Exposure-assessment; Exposure-levels; Exposure-methods; Health-hazards; Inhalants; Inhalation-studies; Mathematical-models; Medical-monitoring; Medical-surveys; Medical-treatment; Organic-chemicals; Particle-aerodynamics; Particulates; Particulate-sampling-methods; Physiological-effects; Physiological-factors; Physiological-response; Physiological-testing; Public-health; Quantitative-analysis; Risk-analysis; Risk-factors; Statistical-analysis
Ken Sexton, University of Texas School of Public Health, Brownsville Regional Campus, RAHC Building, 80 Fort Brown, Brownsville, TX 78520
95-47-6; 71-43-2; 100-41-4; 108-88-3; 79-01-6
Journal of Toxicology and Environmental Health, Part A: Current Issues
University of Minnesota Twin Cities