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Hydrazine
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 302–01–2
NIOSH REL: 0.03 ppm (0.04 mg/m3) 2-hour CEILING; NIOSH considers hydrazine to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL: 1 ppm (1.3 mg/m3) TWA [skin]
1989 OSHA PEL: 0.1 ppm (0.1 mg/m3) TWA [skin]
1993-1994 ACGIH TLV: 0.1 ppm (0.13 mg/m3) TWA [skin], A2
Description of Substance: Colorless, fuming, oily liquid with an ammonia-like odor.
LEL:. . 2.9% (10% LEL, 2,900 ppm)
Original (SCP) IDLH: 80 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that a 4-hour exposure to 80 to 300 ppm killed 14 of 30 rats [Comstock et al. 1954].
Existing short-term exposure guidelines: National Research Council [NRC 1985] Short-term Public Emergency Exposure Guidance Levels (SPEGLs):
1-hour SPEGL: 0.12 ppm
2-hour SPEGL: 0.16 ppm
4-hour SPEGL: 0.03 ppm
8-hour SPEGL: 0.015 ppm
16-hour SPEGL: 0.008 ppm
24-hour SPEGL: 0.005 ppm
ACUTE TOXICITY DATA
Lethal concentration data:
| Species | Reference | LC50 (ppm) | LCLo (ppm) | Time | Adjusted 0.5-hr LC (CF) | Derived value |
|---|---|---|---|---|---|---|
| Rat | ||||||
| Rat | ||||||
| Rat | ||||||
| Rat | ||||||
| Rat | ||||||
| Rat | ||||||
| Mouse |
| Species | Reference | LC50 (ppm) | LCLo (ppm) | Time | Adjusted 0.5-hr LC (CF) | Derived value |
|---|---|---|---|---|---|---|
| Rat Rat
Rat Rat Rat Rat Mouse |
Comstock et al. 1954
Comstock et al. 1954 Comstock et al. 1954 Comstock et al. 1954 Comstock et al. 1954 Jacobson et al. 1955 Jacobson et al. 1955 |
LC17: 190
260 LC33: 270 LC83: 300 630 570 252 |
—–
—– —– —– —– —– —– |
4 hr
4 hr 4 hr 4 hr 1 hr 4 hr 4 hr |
380 ppm (2.0)
520 ppm (2.0) 540 ppm (2.0) 600 ppm (2.0) 788 ppm (1.25) 1,140 ppm (2.0) 504 ppm (2.0) |
38 ppm
52 ppm 54 ppm 60 ppm 79 ppm 114 ppm 50 ppm |
Human data: None relevant for use in determining the revised IDLH.
| Revised IDLH: 50 ppmBasis for revised IDLH: The revised IDLH for hydrazine is 50 ppm based on acute inhalation toxicity data in animals [Comstock et al. 1954; Jacobson et al. 1955]. [Note: NIOSH recommends as part of its carcinogen policy that the “most protective” respirators be worn for hydrazine at concentrations above 0.03 ppm.] |
REFERENCES:
1. Comstock CC, Lawson LH, Greene EA, Oberst FW [1954]. Inhalation toxicity of hydrazine vapor. Arch Ind Hyg Occup Med 10:476-490.
2. Jacobson KH, Clem JH, Wheelwright HJ Jr, Rinehart WE, Mayes N [1955]. The acute toxicity of the vapors of some methylated hydrazine derivatives. AMA Arch Ind Health 12:609-616.
3. NRC [1985]. Emergency and continuous exposure guidance levels for selected airborne contaminants. Vol. 5. Washington, DC: National Academy Press, Committee on Toxicology, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council, pp. 5-21.
4. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 2224.
5. Swiecicki W [1973]. Toksykologia zwiazkow hydrazyny. Med Pr 24:71-79 (in Polish).