Airborne endotoxin and beta-D-glucan in PM1 in agricultural and home environments.
Singh-U; Reponen-T; Cho-KJ; Grinshpun-SA; Adhikari-A; Levin-L; Indugula-R; Green-BJ
Aerosol Air Qual Res 2011 Aug; 11(4):376-386
Objectives: Concentrations of microbial cell wall components such as endotoxin and beta-D-glucan in airborne submicrometer particle size fraction (PM1, defined as particles with median aerodynamic diameter, da less than or equal to 1 mu m) have not been well characterized. In this study, airborne concentrations of endotoxin and beta-D-glucan among different size fractions were quantified in two distinctly different environments: farms and homes. Effect of microbial source (farm type for farms and mold damage for homes) on size-fractionated concentrations was investigated. Methods: Airborne endotoxin and beta-D-glucan were collected on 7 farms and 184 suburban homes using NIOSH two-stage sampler, a cyclone air sampler that fractionates airborne particles into three size fractions: less than or equal to 1 mu m, 1-1.8 mu m and greater than or equal to 1.8 mu m. Results: Geometric means (geometric standard deviations) of airborne total endotoxin concentration on farms and in homes were 1.20 x 10(4) (7.57) EU/m3 and 2.67 (3.82) EU/m3, respectively. Similar values of airborne total beta-D-glucan concentrations were 1.80 x 10(3) (152.88) ng/m3 and 1.91 (2.83) ng/m3, respectively. Relative proportions of PM1 endotoxin, however, were significantly higher (p < 0.001) in home samples (7.9%) than in farm samples (0.3%). Likewise, the proportion of PM1beta-D-glucan was significantly higher (p < 0.001) in homes (28.2% vs. 2.3%). Farm type significantly influenced concentrations of PM1 beta-D-glucan (p < 0.05) and total beta-D-glucan (p < 0.001). Conclusions: The results of this study demonstrate higher proportions of PM1 endotoxin and beta-D-glucan in homes compared to farms. These data further emphasize the importance of conducting size-selective air sampling for microbial exposure assessment in homes.
Aerosol-particles; Aerosols; Aerosol-sampling; Agriculture; Airborne-dusts; Airborne-particles; Air-sampling-techniques; Cell-biology; Dust-particles; Dusts; Mathematical-models; Microbial-test-systems; Microorganisms; Microscopic-analysis; Models; Molds; Particle-aerodynamics; Particulate-sampling-methods; Quantitative-analysis;
Author Keywords: Bioaerosol; Farms; Moldy buildings; Size-Selective sampling; Fine particles
Tiina Reponen, Department of Environmental Health, College of Medicine, University of Cincinnati, Cincinnati, OH
Research Tools and Approaches: Control Technology and Personal Protective Equipment; Healthcare and Social Assistance; Services
Aerosol and Air Quality Research
University of Cincinnati