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Nitrogen dioxide
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 10102–44–0
NIOSH REL: 1 ppm (1.8 mg/m3) STEL
Current OSHA PEL: 5 ppm (9 mg/m3) CEILING
1989 OSHA PEL: 1 ppm (1.8 mg/m3) STEL
1993-1994 ACGIH TLV: 3 ppm (5.6 mg/m3) TWA, 5 ppm (9.4 mg/m3) STEL
Description of substance: Yellowish-brown liquid or reddish-brown gas (above 70°F) with a pungent, acrid odor.
LEL :. . Noncombustible Liquid/Nonflammable Gas
Original (SCP) IDLH: 50 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that concentrations above 50 ppm are considered dangerous to man for short exposures. Also, NIOSH [1974] cited a rat 4-hour LC50 of 68 ppm [Gray et al. 1954].
Existing short-term exposure guidelines: American Industrial Hygiene Association [AIHA 1964] Emergency Exposure Limits (EELs):
5-minute EEL: 35 ppm
15-minute EEL: 25 ppm
30-minute EEL: 20 ppm
60-minute EEL: 10 ppm
National Research Council [NRC 1985] Short-term Public Emergency Guidance Levels (SPEGLs):
1-hour SPEGL: 1 ppm
2-hour SPEGL: 0.5 ppm
4-hour SPEGL: 0.25 ppm
8-hour SPEGL: 0.12 ppm
16-hour SPEGL: 0.06 ppm
24-hour SPEGL: 0.04 ppm
ACUTE TOXICITY DATA:
Lethal concentration data:
| Species | Reference | LC50 (ppm) | LCLo (ppm) | Time | Adjusted 0.5-hrLC (CF*) | Derived value |
|---|---|---|---|---|---|---|
| G. pigRabbit
Rat Rat Mouse Dog Monkey |
Buckley & Balchum 1965Carson et al. 1962
Gray et al. 1954 Gray et al. 1954 Hialado & Machado 1977 Steadman et al. 1966 Steadman et al. 1966 |
30315
68 138 1,000 —– —– |
———-
—– —– —– 64 64 |
1 hr15 min
4 hr 30 min 10 min 8 hr 8 hr |
37 ppm (1.22)258 ppm (0.82)
123 ppm (1.81) 138 ppm (1.0) 730 ppm (0.73) 141 ppm (2.21) 141 ppm (2.21) |
3.7 ppm26 ppm
12 ppm 14 ppm 73 ppm 14 ppm 14 ppm |
*Note: Conversion factor (CF) was determined with “n” = 3.5 [ten Berge et al. 1986].
Human data: It has been reported that 10 to 20 ppm has been mildly irritating [Patty 1963]. Exposure to 150 ppm or more (no time period given) has been reported to cause death from pulmonary edema [NRC 1979]. It has been predicted that 50% lethality would occur following exposure to 174 ppm for 1 hour [Book 1982].
| Revised IDLH: 20 ppmBasis for revised IDLH: The revised IDLH for nitrogen dioxide is 20 ppm based on acute inhalation toxicity data in humans [Patty 1963]. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations above 20 ppm. |
REFERENCES:
1. American Industrial Hygiene Association, Toxicology Committee [1964]. Emergency exposure limits. Am Ind Hyg Assoc J 25:578-586.
2. Book SA [1982]. Scaling toxicity from laboratory animals to people: an example with nitrogen dioxide. J Toxicol Environ Health 9:719-725.
3. Buckley RD, Balchum OJ [1965]. Acute and chronic exposures to nitrogen dioxide. Effects on oxygen consumption and enzyme activity on guinea pig tissues. Arch Environ Health 10:220-223.
4. Carson TR, Rosenholtz MS, Wilinski FT, Weeks MH [1962]. The responses of animals inhaling nitrogen dioxide for single, short-term exposures. Am Ind Hyg Assoc J 23:457-462.
5. Gray E LeB, Patton FM, Goldberg SB, Kaplan E [1954]. Toxicity of the oxides of nitrogen. II. Acute inhalation toxicity of nitrogen dioxide, red fuming nitric acid, and white fuming nitric acid. AMA Arch Ind Hyg Occup Med 10:418-422.
6. Hialado CJ, Machado AM [1977]. Effect of nitrogen dioxide on Swiss albino mice. J Combustion Toxicol 4:246-253.
7. NIOSH [1974]. QW98000. Nitrogen dioxide. In: The toxic substances list, 1974 ed. Rockville, MD: U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 74-134, p. 534.
8. NRC [1979]. Nitrogen dioxide: an assessment of the health effects of short-term exposure. Washington, DC: National Academy of Sciences, National Research Council, Committee on Toxicology.
9. NRC [1985]. Emergency and continuous exposure guidance levels for selected airborne contaminants. Vol. 4. Washington, DC: National Academy Press, Committee on Toxicology, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council, pp. 83-95.
10. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., pp. 919-923.
11. Steadman BL, Jones RA, Rector DE, Siegel J [1966]. Effects on experimental animals of long-term continuous inhalation of nitrogen dioxide. Toxicol Appl Pharmacol 9(1):160-170.
12. ten Berge WF, Zwart A, Appelman LM [1986]. Concentration-time mortality response relationship of irritant and systematically acting vapours and gases. J Haz Mat 13:301-309.