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

CAS number: 108–93–0

NIOSH REL: 50 ppm (200 mg/m3) TWA [skin]

Current OSHA PEL: 50 ppm (200 mg/m3) TWA

1989 OSHA PEL: 50 ppm (200 mg/m3) TWA [skin]

1993-1994 ACGIH TLV: 50 ppm (206 mg/m3) TWA [skin]

Description of Substance: Sticky solid or colorless to light-yellow liquid (above 77 F) with a camphor-like odor.

LEL: . . Unknown

Original (SCP) IDLH: 3,500 ppm

Basis for original (SCP) IDLH: No acute inhalation toxicity data are available on which to base an IDLH for cyclohexanol. The chosen IDLH, therefore, has been estimated from the rabbit oral LD50 of 2.2 to 2.6 g/kg [Treon et al. 1943 cited in Browning 1965]. The chosen IDLH of 3,500 ppm (14.3 g/m3) is probably conservative, because the lower end of the range of the LD50 values (i.e., 2.2 g/kg) has been used to estimate the IDLH.

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value
RatRabbit Bar and Griepentrog 1967Treon et al. 1943 oraloral 2,0602,200-2,600 ———- 3,458 ppm3,693-4,365 ppm 346 ppm369-437 ppm


Human data: The estimated acceptable concentration for 8 hours was reported in volunteers to be less than 100 ppm [Nelson et al. 1943].



1. Bar F, Griepentrog F [1967]. Die situation in der gesundheitlichen beurteilung der aromaliscerungsmittel für lebensmittel. Med Ernahr 8:282-251. [From ACGIH [1991]. Cyclohexanol. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 357-358.]

2. Browning E [1965]. Toxicity and metabolism of industrial solvents. New York, NY: Elsevier Publishing Company, p. 387.

3. Nelson KW, Ege JF, Ross M, Woodman LE, Silverman L [1943]. Sensory response to certain industrial solvent vapors. J Ind Hyg Toxicol 25(7):282-285.

4. Treon JF, Crutchfield WE Jr, Kitzmiller KV [1943]. The physiological response of rabbits to cyclohexane, methyl cyclohexane, and certain derivatives of these compounds. I. Oral administration and cutaneous application. J Ind Hyg Toxicol 25(6):199-214.