Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 94-36-0
NIOSH REL: 5 mg/m3 TWA
Current OSHA PEL:5 mg/m3 TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 5 mg/m3 TWA
Description of Substance: Colorless to white crystals or a granular powder with a faint, benzaldehyde-like odor.
Original (SCP) IDLH: 7,000 mg/m3
Basis for original (SCP) IDLH: The chosen IDLH is based on the estimated mouse 4-hour LC50 of 700 ppm (7,000 mg/m3) for benzoyl peroxide cited by ACGIH . However, this concentration is not an actual LC50 value for benzoyl peroxide; it was estimated by ACGIH  by analogy from data concerning LC50 values for other related organic peroxides [Floyd and Stokinger 1958].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
|Species||Reference||LC50||LCLo||Time||Adjusted 0.5-hr LC (CF)||Derived Value PPM|
|Mouse||Floyd and Stokinger 1958||7,000 mg/m3||—–||4 hr||14,000 mg/m3 (2.0)||1,400 mg/m3|
Lethal dose data:
|Species||Reference||Route||LD50(mg/kg)||LDLo(mg/kg)||Adjusted LD||Derived Value|
|Mouse||ARCO 1982||oral||7,710||—–||53,970 mg/m3||5,397 mg/m3|
Human data: Concentrations of 12 mg/m3 and higher have resulted in pronounced irritation of the nose and throat [Moskowitz and Grabois 1950].
Revised IDLH: 1,500 mg/m3
Basis for revised IDLH: The revised IDLH for benzoyl peroxide is 1,500 mg/m3 based on acute inhalation toxicity data in animals [Floyd and Stokinger 1958].
- ACGIH . Acetaldehyde. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 23-24.
- ARCO . Toxicology report. 70% aqueous tertiary butyl hydroperoxide: acute toxicity evaluation. Newtown Square, PA: Arco Chemical Company, June 1982.
- Floyd EP, Stokinger HE . Toxicity studies of certain organic peroxides and hydroperoxides. Am Ind Hyg Assoc J 19:205-212.
- Moskowitz S, Grabois B . Unpublished report sent to ACGIH. Albany, NY: New York State Department of Labor, Division of Industrial Hygiene (November 1950). [From ACGIH . Benzoyl peroxide. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 123-124.]