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Propylene Oxide

General Description

  • Synonyms: 1,2-Epoxy propane; Propene oxide; Methyloxidrane
  • OSHA IMIS Code Number: 2215
  • Chemical Abstracts Service (CAS) Registry Number: 75-56-9
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: TZ2975000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: 1280 127P
  • NIOSH Pocket Guide to Chemical Hazards, Propylene Oxide: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

  • OSHA Permissible Exposure Limit (PEL):
  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 2 ppm, 4.75 mg/m3 TWA; Sensitizer; Appendix A3 - Confirmed Animal Carcinogen with Unknown Relevance to Humans
  • National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix A - NIOSH Potential Occupational Carcinogens

Health Factors

  • Carcinogenic Classification:
  • NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 400 ppm
  • Potential Symptoms: Irritation of eyes, skin respiratory system; cough, sore throat; skin blisters, burns; skin sensitization; blindness on contact with liquid; (potential occupational carcinogen)
  • Health Effects: Irritation-Eye, Nose, Throat, Skin---Moderate (HE15); CNS depression (HE7); Cumulative liver damage (HE3); mutagen---OSHA Select Carcinogen (HE2).
  • Affected Organs: Eyes, skin, respiratory system
  • Notes:
    1. Vapor/air mixtures are explosive. Odor warning is insufficient when toxic concentrations are present.
    2. Can form adducts with DNA and proteins (e.g., hemoglobin).
    3. Metabolized in several tissues by glutathione-S-transferase and epoxide hydrolase.
  • Literature Basis:
    • NIOSH Pocket Guide to Chemical Hazards: Propylene Oxide.
    • International Chemical Safety Cards (WHO/IPCS/ILO): Propylene Oxide.
    • Czene, K., et al.: Analysis of DNA and hemoglobin adducts and sister chromatid exchanges in a human population occupationally exposed to propylene oxide: a pilot study. Cancer Epidemiol. Biomarkers Prev. 11(3): 315-318, 2002.
    • Faller, T.H., Csanady, G.A., Kreuzer, P.E., Bauer, C.M. and Filser, J.G.: Kinetics of propylene oxide metabolism in microsomes and cytosol of different organs from mouse, rat, and humans. Toxicol. Appl. Pharmacol. 172(1): 62-74, 2001.
    • Pohanish, R.P. (editor): Propylene Oxide. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1978-1980.
  • Date Last Revised: 03/08/2004

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):
  • Anasorb 747 Tube (140/70 mg sections)
  • maximum volume: 5 Liters
  • maximum flow rate: 0.1 L/min
  • current analytical method: Gas Chromatography; GC/FID
  • analytical solvent: Carbon Disulfide
  • method reference: OSHA Analytical Method (OSHA 88)
  • method classification: Fully Validated
On-Site Sampling Techniques/Methods:
  • Detector Tube
  • manufacturer: Gastec
  • model/type: 163
  • sampling information: 1 stroke
  • upper measurement limit: 3.9%
  • detection limit: approximately 0.03%
  • overall uncertainty: 25% for 0.06 to 1.3%, 16% for 1.3 to 3.9%
  • method reference: on-site air secondary (manufacturer)
  • Detector Tube
  • manufacturer: Gastec
  • model/type: 163L
  • sampling information: 1 stroke
  • upper measurement limit: 100 ppm
  • detection limit: approximately 0.5 ppm
  • overall uncertainty: 16%
  • method reference: on-site air secondary (manufacturer)
  • Detector Tube
  • manufacturer: Matheson-Kitagawa
  • model/type: 8014-163SA
  • sampling information: 0.5 or 1 stroke
  • upper measurement limit: 5%
  • detection limit: approximately 0.05%
  • overall uncertainty: unknown
  • method reference: on-site air secondary (manufacturer)

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