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

CAS number: 98–82–8

NIOSH REL: 50 ppm (245 mg/m3) TWA [skin]

Current OSHA PEL: 50 ppm (245 mg/m3) TWA [skin]

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 50 ppm (246 mg/m3) TWA [skin]

Description of Substance: Colorless liquid with a sharp, penetrating, aromatic odor.

LEL: . . 0.9% (10% LEL, 900 ppm)

Original (SCP) IDLH: 8,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the rat 4-hour LC50 of 8,000 ppm [Smyth et al. 1951 cited by AIHA 1961].

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50(ppm) LCLo(ppm) Time Adjusted 0.5-hrLC (CF) Derivedvalue
RatMouse Smyth et al. 1951Werner et al. 1944 —–2,000 8,000—– 4 hr7 hr 16,000 ppm (2.0)4,800 ppm (2.4) 1,600 ppm480 ppm


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value
MouseRat Sologob 1971Wolf et al. 1956 oraloral 12,7501,400 ———- 17,850 ppm1,960 ppm 1,785 ppm196 ppm


Other animal data: Daily exposures of rats to 500 ppm for 5 months resulted in no significant blood changes, although hyperemia and congestion were noted in the lungs, liver, and kidneys [Clayton and Clayton 1981].

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



1. AIHA [1961]. Cumene. In: Hygienic guide series. Am Ind Hyg Assoc J 22:522-524.

2. Clayton GD, Clayton FE, eds. [1981]. Patty’s industrial hygiene and toxicology. 3rd rev. ed. Vol. 2B. Toxicology. New York, NY: John Wiley & Sons, Inc., pp. 3308-3310.

3 Smyth HF Jr, Carpenter CP, Weil CS [1951]. Range-finding toxicity data: list IV. AMA Arch Ind Hyg Occup Med 4:119-122.

4. Sologob AM [1971]. Experimental study on substantiation of the hygienic standard values of metadiisopropylbenzol and paradiisopropylbenzol in water bodies. Gig Sanit 36(9):18-21 (in Russian).

5. Werner HW, Dunn RC, von Oettingen WF [1944] The acute effects of cumene vapors in mice. J Ind Hyg Toxicol 26:264-268.

6. Wolf MA, Rowe VK, McCollister DD, Hollingsworth RL, Oyen F [1956]. Toxicological studies of certain alkylated benzenes and benzene. Experiments on laboratory animals. AMA Arch Ind Health 14:387-398.