Characterization of an Aerosol Chamber for Human Exposures to Endotoxin

Details

• Personal Author:
  Boehlecke, Brian A. ; Jacobs RR ; Parker CR ; Taylor L
• Description:
  The objective of this study was to develop and characterize an exposure chamber in which human subjects could be exposed to low dust concentrations carrying an endotoxin coating. An exposure chamber, dust dispersion method, and endotoxin characterization technique were developed for inhalation exposures. A 6.27 m3 exposure chamber was designed and constructed from cinder block, glass windows, and Plexiglas. Using an acetone adhesion process, Enterobacter agglomerans were adsorbed onto respirable cellulose particles to create the endotoxin aerosol. The size distribution of the endotoxin-treated particles was verified using light microscopy and cascade impactors. A dry powder dust generator was refined to consistently disperse small quantities of the aerosol into the chamber to maintain dust concentrations at approximately 250 mug/m3. Dust levels during the chamber exposures were monitored using a portable continuous aerosol monitor (PCAM). During initial exposure runs, PCAM monitoring stations were positioned at different locations within a 0.5-meter matrix to document mixing patterns. Total dust and cascade impactor samples were collected throughout each exposure period to characterize the chamber operating system and insure the mean airborne dust concentration fulfilled target levels. A one-factor analysis of variance at the 95 percent confidence interval illustrated that there was not a statistically significant difference in the mean dust concentration throughout the exposure runs compared to the individual runs. Together the consistency of the total dust filters, endotoxin concentrations, and aerosol-monitoring instrument were adequate to allow use of the chamber for experimental studies involving human volunteers. [Description provided by NIOSH]
• Subjects:
  Aerosols Dust Endotoxins Occupational Health Particulate Matter Respiratory System Safety
• Keywords:
  Aerosol Dispersion Aerosol Particles Author Keywords: Aerosol Chamber Chamber Characterization Dust Exposure Dust Particles Dusts Endotoxin-Aerosol Exposure Chambers Inhalation Studies Microscopy Monitoring Systems Monitors

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• ISSN:
  1047-322X
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DSHEFS - Division of Surveillance, Hazard Evaluations, and Field Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  303-312
• Volume:
  15
• Issue:
  3
• NIOSHTIC Number:
  nn:20020829
• Citation:
  Appl Occup Environ Hyg 2000 Mar; 15(3):303-312
• Federal Fiscal Year:
  2000
• Peer Reviewed:
  True
• Source Full Name:
  Applied Occupational and Environmental Hygiene
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:1dfcf805d1f0bbcc52c41c36a6cfd27e1be6e2046ac4d37af69bca6daf7812a3cc8cd2a1f30d0a2a8a307bf40fb5729b56e550f81624b8bdfcd95c9f6fbc4ae3
• Download URL:
  https://stacks.cdc.gov/view/cdc/198491/cdc_198491_DS1.pdf
• File Type:
  [PDF - 946.15 KB ]