Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 7664–93–9
NIOSH REL: 1 mg/m3 TWA
Current OSHA PEL: 1 mg/m3 TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 1 mg/m3 TWA, 3 mg/m3 STEL
Description of substance: Colorless to dark-brown, oily, odorless liquid.
LEL: . . Noncombustible Liquid
Original (SCP) IDLH: 80 mg/m3
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by ACGIH  that guinea pigs died after 2.75 hours of exposure at 87 mg/m3 [Treon et al. 1950].
Existing short-term exposure guidelines: National Research Council [NRC 1984] Emergency Exposure Guidance Levels (EEGLs):
10-minute EEGL: 5 mg/m3
30-minute EEGL: 2 mg/m3
60-minute EEGL: 1 mg/m3
ACUTE TOXICITY DATA:
Lethal concentration data:
|Species||Reference||LC50||LCLo||Time||Adjusted 0.5-hr |
|G. pig||Amdur et al. 1952a||50 mg/m3||-----||8 hr||125 mg/m3 (2.5)||13 mg/m3|
|Rat||Izmerov et al. 1982||510 mg/m3||-----||2 hr||816 mg/m3 (1.6)||82 mg/m3|
|Mouse||Izmerov et al. 1982||320 mg/m3||-----||2 hr||512 mg/m3 (1.6)||51 mg/m3|
|G. pig||Raule 1954||18 mg/m3||-----||?||?||?|
|G. pig||Treon et al. 1950||-----||87 mg/m3||2.75 hr||154 mg/m3 (1.77)||15 mg/m3|
Lethal dose data:
|Adjusted LD||Derived value|
|Rat||Smyth et al. 1969||oral||2,140||-----||14,980 mg/m3||1,498 mg/m3|
Human data: In exposures of 5 to 15 minutes, some volunteers found 5 mg/m3 to be very objectionable, while others found it less so [Amdur et al. 1952b]. The lethal oral dose has been reported to be 135 mg/kg [Arena 1970]. [Note: An oral dose of 135 mg/kg is equivalent to a worker being exposed to about 6,300 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]
|Revised IDLH: 15 mg/m3 |
Basis for revised IDLH: The revised IDLH for sulfuric acid is 15 mg/m3 based on acute inhalation toxicity data in humans [Amdur et al. 1952b] and animals [Amdur et al. 1952a; Treon et al. 1950]. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations above 5 mg/m3.
1. ACGIH . Sulfuric acid. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 239-240.
2. Amdur MO, Schulz RZ, Drinker P [1952a]. Toxicity of sulfuric acid mist to guinea pigs. AMA Arch Ind Hyg Occup Med 5:318-329.
3. Amdur MO, Silverman L, Drinker P [1952b]. Inhalation of sulfuric acid mist by human subjects. AMA Arch Ind Hyg Occup Med 6(4):305-313.
4. Arena JM . Poisoning, toxicology, symptoms, treatments. 2nd ed. Springfield, IL: C.C. Thomas, p. 73.
5. Izmerov NF, Sanotsky IV, Sidorov KK . Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 107.
6. NRC . Emergency and continuous exposure limits for selected airborne contaminants. Vol. 1. Washington, DC: National Academy Press, Committee on Toxicology, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council, pp. 107-112.
7. Raule A . Occupational diseases caused by sulfuric acid. Med Lav 45:590-599 (in Italian).
8. Smyth HF Jr, Carpenter CP, Weil CS, Pozzani UC, Striegel JA, Nycum JS . Range-finding toxicity data: list VII. Am Ind Hyg Assoc J 30(5):470-476.
9. Treon JF, Dutra FR, Cappel J, Sigmon H, Younker W . Toxicity of sulfuric acid mist. AMA Arch Ind Hyg Occup Med 2:716-734.
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