Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to site content Skip directly to page options
CDC Home

Isobutyl alcohol

May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 78–83–1

NIOSH REL: 50 ppm (150 mg/m3) TWA

Current OSHA PEL: 100 ppm (300 mg/m3) TWA

1989 OSHA PEL: 50 ppm (150 mg/m3) TWA

1993-1994 ACGIH TLV: 50 ppm (152 mg/m3) TWA

Description of substance: Colorless, oily liquid with a sweet, musty odor.

LEL(@123°F): 1.7% (10% LEL(@123°F), 1,700 ppm)

Original (SCP) IDLH: 8,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that 2 of 6 rats died when exposed for 4 hours to 8,000 ppm [Smyth et al. 1954].

Short-term exposure guidelines: None developed


Lethal concentration data:





TimeAdjusted 0.5-hr


Derived value
RatSmyth et al. 1954LC33: 8,000-----4 hr16,000 ppm (2.0)1,600 ppm

Lethal dose data:





Adjusted LDDerived value


Munch and Schwartze 1925

Smyth et al. 1954







8,522 ppm

5,591 ppm

852 ppm

559 ppm

Other animal data: RD50 (mouse), 1,818 ppm [DeCeaurriz et al. 1981].

Human data: None relevant for use in determining the revised IDLH.

Revised IDLH: 1,600 ppm

Basis for revised IDLH: The revised IDLH for isobutyl alcohol is 1,600 ppm based on acute inhalation toxicity data in animals [Smyth et al. 1954]. This may be a conservative value due to the lack of relevant acute toxicity data for workers.


1. DeCeaurriz JC, Micillino JC, Bonnet P, Guenier JP [1981]. Sensory irritation caused by various industrial airborne chemicals. Toxicol Lett 9(2):137-143.

2. Munch JC, Schwartze EW [1925]. Narcotic and toxic potency of aliphatic alcohols upon rabbits. J Lab Clin Med 10:985-995.

3. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1448.

4. Smyth HF Jr, Carpenter CP, Weil CS, Pozzani UC [1954]. Range-finding toxicity data: list V. AMA Arch Ind Hyg Occup Med 10:61-68.

Contact Us:
  • Page last reviewed: December 4, 2014
  • Page last updated: December 4, 2014 The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Rd. Atlanta, GA 30329-4027, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC-INFO