Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 76–22–2
NIOSH REL: 2 mg/m3 TWA
Current OSHA PEL: 2 mg/m3 TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 12 mg/m3 (2 ppm) TWA, 19 mg/m3 (3 ppm) STEL
Description of Substance: Colorless or white crystals with a penetrating, aromatic odor.
LEL: . . 0.6% (10% LEL, 3,600 mg/m3)
Original (SCP) IDLH: 200 mg/m3
Basis for original (SCP) IDLH: No data on acute inhalation toxicity are available on which to base an IDLH for camphor. For this draft technical standard, therefore, the chosen IDLH is based on a report by Gronka et al.  concerning the camphor processing and packaging area of a plant. Concentrations of camphor ranging from 3 to 194 mg/m3 produced nose and sinus irritation among workers in this plant [Gronka et al. 1969].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
|Species||Reference||LC50||LCLo||Time||Adjusted 0.5-hrLC (CF)||DerivedValue|
|Mouse||Nikolaeva 1957||—–||400 mg/m3||3 hr||720 mg/m3 (1.8)||72 mg/m3|
Lethal dose data:
|Species||Reference||Route||LD50(mg/kg)||LDLo(mg/kg)||Adjusted LD||Derived value|
|Flury and Zernik 1935Horikawa and Okada 1975
Smith and Margolis 1954
|5,600 mg/m39,170 mg/m3
|560 mg/m3917 mg/m3
Human data: It has been reported that concentrations during camphor processing and packaging ranged from 33 to 194 mg/m3; workers had no complaints other than slight eye irritation and afternoon drowsiness [Gronka et al. 1969].
|Revised IDLH: 200 mg/m3 [Unchanged]Basis for revised IDLH: Based on chronic inhalation toxicity data in workers [Gronka et al. 1969], the original IDLH for synthetic camphor (200 mg/m3) is not being revised at this time.|
1. Flury F, Zernik F . Zusammenstellung der toxischen und letalen dosen für die gebräuchlichsten gifte und versuchstiere. Abder Hand Biol Arbeitsmethod 4:1289-1422 (in German).
2. Gronka PA, Bobkoski RL, Tomchick GJ, Rakow AB . Camphor exposures in a packaging plant. Am Ind Hyg Assoc J 30:276-279.
3. Horikawa E, Okada T . Experimental study on acute toxicity of phenol camphor. Shika Gakuho (Journal of Dentistry) 75:934-939 (in Japanese).
4. Nikolaeva . Toxicological evaluation of camphor vapors. Gig Sanit 22(11):83-86 (in Russian).
5. Smith AG, Margolis G . Camphor poisoning: anatomical and pharmacologic study; report of a fatal case; experimental investigation of protective action of barbiturate. Am J Pathol 30(5):857-868.