Propylene oxide

Agent Name
Propylene oxide
Alternative Name
1,2-Epoxypropane
CAS Number
75-56-9
Formula
C3-H6-O
Major Category
Pesticides
Propylene oxide formula graphical representation
Synonyms
1,2-Epoxy propane; Methyl ethylene oxide; Methyloxirane; Propene oxide; 1,2-Propylene oxide; 1,2-Epoxypropane; 1,2-Epoxypropane; [NIOSH] UN1280;
Category
Fumigants
Description
Colorless liquid with a benzene-like odor. [Note: A gas above 94 degrees F.] [NIOSH]
Sources/Uses
Used mainly as a chemical intermediate; it has been used as a food fumigant (dried fruit and bulk), but use was restricted in 1996 by the EPA. [ACGIH] Used to prepare slides for electron microscopy and to disinfect the skin; [Kanerva, p. 1831]
Comments
Liquid causes first degree burns on short exposure. [CHRIS] Allergic contact dermatitis reported in a worker swabbing skin with a disinfectant; [Kanerva, p. 1831] Can cause CNS depression and severe eye injuries; A respiratory irritant that may cause pulmonary edema; [CAMEO] Causes mild CNS depression in animals after inhalation of high concentrations; A nasal carcinogen in rodents at concentrations causing irritation; NOAEL is 50 ppm; Detoxified more rapidly than ethylene oxide, and this is one of the reasons for the lower carcinogenic potency of propylene oxide; A dermal sensitizer; [ACGIH] Propylene oxide (UN1280) has warning of explosive polymerization; [ERG 2016]
Restricted
Restricted use as a food fumigant by EPA in 1996 because of Delaney clause (animal carcinogen); [ACGIH]
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
Insufficient data
TLV (ACGIH)
2 ppm
PEL (OSHA)
100 ppm
MAK
2 ppm
IDLH (NIOSH)
400 ppm
Excerpts from Documentation for IDLHs
Basis for original (SCP) IDLH: The chosen IDLH is based on the dog 4­hour LCLO of 2,005 ppm and the mouse 4­hour LC50 of 1,740 ppm [Jacobson et al. 1956 cited by NIOSH 1976]. . . . Human data: None relevant for use in determining the revised IDLH.
Vapor Pressure
538 mm Hg
Odor Threshold Low
10 ppm
Odor Threshold High
199 ppm
Lethal Concentration
LC50 (rat) = 4,000 ppm/4H
Explosive Polymerization
Yes
Explanatory Notes
Detection odor threshold from AIHA (mean = 45 ppm); Flash point = -35 deg F; [CHEMINFO] VP from HSDB;
Reference Link #2
NFPA
burn readily
ERPG-1
50 ppm
ERPG-2
250 ppm
ERPG-3
750 ppm

Adverse Effects

Skin Sensitizer
Yes
Toxic Pneumonitis
Yes
Neurotoxin
Other CNS neurotoxin
Dermatotoxin
Skin burns
IARC Carcinogen
Possible (2b)
NTP Carcinogen
Anticipated human carcinogen
ACGIH Carcinogen
Confirmed Animal

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent:

Processes

Industrial Processes with risk of exposure: