title: Estimation of occupational and nonoccupational nitrogen dioxide exposure for Korean taxi drivers using a microenvironmental model.
abstract: Occupational and nonoccupational personal nitrogen dioxide (NO(2)) exposures were measured using passive samplers for 31 taxi drivers in Asan and Chunan, Korea. Exposures were also estimated using a microenvironmental time-weighted average model based on indoor, outdoor and inside the taxi area measurements. Mean NO(2) indoor and outdoor concentrations inside and outside the taxi drivers' houses were 24.7+/-10.7 and 23.3+/-8.3 ppb, respectively, with a mean indoor to outdoor NO(2) ratio of 1.1. Mean personal NO(2) exposure of taxi drivers was 30.3+/-9.7 ppb. Personal NO(2) exposures for drivers were more strongly correlated with interior vehicle NO(2) levels (r = 0.89) rather than indoor residential NO(2) levels (r = 0.74) or outdoor NO(2) levels (r = 0.71). The main source of NO(2) exposure for taxi drivers was considered to be occupational driving. Interestingly, the NO(2) exposures for drivers' using LPG-fueled vehicles (26.3+/-1.3 ppb) were significantly lower than those (38.1+/-1.3 ppb) using diesel-fueled vehicle (P <0.01). Since drivers spent most of their time inside their vehicle and indoors at home, a microenvironmental model was used to estimate the personal NO(2) exposure with indoor and outdoor NO(2) levels of the residence, and interior vehicle NO(2) levels (P <0.001). Some subpopulations, such as professional drivers, might be exposed to high NO(2) levels because they drive diesel-using vehicles outdoors in Korea.
authors.affiliation: Department of Environmental Health Science, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-Si, Choongchungnam-do 336-745, South Korea. sonbss@sch.ac.kr
authors.forename: Busoon
authors.initials: B
authors.lastname: Son
authors.forename: Wonho
authors.initials: W
authors.lastname: Yang
authors.forename: Patrick
authors.initials: P
authors.lastname: Breysse
authors.forename: Taewoong
authors.initials: T
authors.lastname: Chung
authors.forename: Youngshin
authors.initials: Y
authors.lastname: Lee
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D001336:Automobiles; D005742:Gasoline; D006801:Humans; D007723:Korea; D008956:Models, Chemical; D009585:Nitrogen Dioxide / Q000032:analysis*; D016273:Occupational Exposure
chemical_list: D000395:Air Pollutants, Occupational; D005742:Gasoline; D009585:Nitrogen Dioxide