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Phosgene

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

CAS number: 75–44–5

NIOSH REL: 0.1 ppm (0.4 mg/m3) TWA,

0.2 ppm (0.8 mg/m3) 15-minute CEILING

Current OSHA PEL: 0.1 ppm (0.4 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.1 ppm (0.40 mg/m3) TWA

Description of substance: Colorless gas with a suffocating odor like musty hay.

LEL: . . Nonflammable Gas

Original (SCP) IDLH: 2 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Jacobs [1967] that 1 part in 200,000 (5 ppm) is probably lethal for exposures of 30 minutes. Gross et al. [1965] indicated that concentrations as low as 0.5 ppm for 2 hours caused definite pathological changes in the lungs of rats sacrificed 96 hours post exposure; the investigators believed some abnormalities were present 3 months after rats had been exposed at 2 ppm for 80 minutes. An IDLH of 2 ppm is used for phosgene to prevent irreversible adverse health effects.

Existing short-term exposure guidelines: National Research Council [NRC 1984] Emergency Exposure Guidance Levels (EEGLs):

1-hour EEGL: 0.2 ppm

24-hour EEGL: 0.02 ppm

ACUTE TOXICITY DATA:

Lethal concentration data:

Species Reference LC50 (ppm) LCLo (ppm) Time Adjusted 0.5-hr LC (CF) Derived value
Human Diller 1978 500 —– 1 min 160 ppm (0.32) 16 ppm
Human Diller 1978 —– 3 2.83 hr 5.3 ppm (1.78) 0.5 ppm
Human Diller 1978 —– 30 17 min 25 ppm (0.82) 2.5 ppm
Mammal Flury 1928 —– 50 5 min 28 ppm (0.55) 2.8 ppm
Human Izmerov et al. 1982 —– 88 30 min 88 ppm (1.0) 8.8 ppm
Cat Izmerov et al. 1982 —– 46 15 min 37 ppm (0.79) 3.7 ppm
Rat NDRC 1946 340 —– 30 min 340 ppm (1.0) 34 ppm
Mouse NDRC 1946 438 —– 30 min 438 ppm (1.0) 44 ppm
Rabbit NDRC 1946 243 —– 30 min 243 ppm (1.0) 24 ppm
G. pig NDRC 1946 316 —– 30 min 316 ppm (1.0) 32 ppm
Dog NDRC 1946 1,022 —– 20 min 981 ppm (0.96) 98 ppm
Monkey NDRC 1946 145 —– 1 min 46 ppm (0.32) 4.6 ppm
Human Tab Biol Per 1933 —– 50 5 min 28 ppm (0.55) 2.8 ppm
Mammal Tab Biol Per 1933 —– 2.7 30 min 2.7 ppm (1.0) 0.3 ppm

Other animal data: It has been reported that concentrations as low as 0.5 ppm for 2 hours caused definite pathological changes in the lungs of rats sacrificed 96 hours post exposure; the investigators believed some abnormalities were present 3 months after the rats had been exposed at 2 ppm for 80 minutes [Gross et al. 1965].

Other human data: It has been calculated that based on acute toxicity data in humans, the lethal dose for a 30-minute exposure would be about 17 ppm [Diller 1978]. It has been stated that 25 ppm for 30 to 60 minutes is dangerous and brief exposure to 50 ppm may be rapidly fatal [Henderson and Haggard 1943]. It has also been stated that 5 ppm is probably lethal for a 30-minute exposure [Jacobs 1967].

REFERENCES:

1. Diller WF [1978]. Medical phosgene problems and their possible solution. J Occup Med 20:189-193.

2. Flury F [1928]. Moderne gewerbliche vergiftungen in pharmakologisch-toxikologischer hinsicht (Pharmacological-toxicological aspects of intoxicants in modern industry). Arch Exp Pathol Pharmakol 138:65-82 (translated).

3. Gross P, Rinehart WE, Hatch T [1965]. Chronic pneumonitis caused by phosgene. Arch Environ Health 10:768-775.

4. Henderson Y, Haggard HW [1943]. Noxious gases. 2nd ed. New York, NY: Reinhold Publishing Corporation, pp. 137-138.

5. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 99.

6. Jacobs MB [1967]. The analytical toxicology of industrial inorganic poisons. New York, NY: Interscience Publishers, pp. 648-649.

7. NDRC [1946]. Summary technical report of division 9, NDRC. Vol 1. Chemical warfare agents and related chemical problems. Parts I-II. Washington, DC: National Defence Research Committee, pp. 1-385.

8. NRC [1984]. Emergency and continuous exposure limits for selected airborne contaminants. Vol. 2. Washington, DC: National Academy Press, Committee on Toxicology, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council, pp. 69-86.

9. Tab Biol Per [1933]; 3:231 (in German).