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Zinc chloride fume

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

CAS number: 7646–85–7

NIOSH REL: 1 mg/m3 TWA, 2 mg/m3 STEL

Current OSHA PEL: 1 mg/m3 TWA

1989 OSHA PEL: 1 mg/m3 TWA, 2 mg/m3 STEL

1993-1994 ACGIH TLV: 1 mg/m3 TWA, 2 mg/m3 STEL

Description of substance: White particulate dispersed in air.

LEL: . . Noncombustible Solid

Original (SCP) IDLH*: 4,800 mg/m3 [*Note: “Effective” IDLH = 2,000 mg/m3 — see discussion below.]

Basis for original (SCP) IDLH: The chosen IDLH is based on the 30-minute human TCLO of 4,800 mg/m3 zinc chloride [Ferry 1974 cited by NIOSH 1976]; and the toxic effects involved the respiratory system. No other data on acute inhalation toxicity are available on which to base the IDLH for zinc chloride fume. Because of the assigned protection factor afforded by each device, however, 2,000 ´ the OSHA PEL (i.e., 2,000 mg/m3) is the concentration above which only the “most protective” respirators are permitted.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50 LCLo Time Adjusted 0.5-hrLC (CF) Derived value
Rat Karlsson et al. 1986 LC67: 1,960 mg/m3 —– 10 min 1,352 mg/m3 135 mg/m3
Rat Marrs et al. 1983 1,260 mg/m3 —– 30 min 1,260 mg/m3 126 mg/m3
Rabbit Marrs et al. 1983 LC70: 1,260 mg/m3 —– 30 min 1,260 mg/m3 126 mg/m3
Mouse Marrs et al. 1983 11,80 mg-min/m3 —– —– 393 mg/m3 39 mg/m3

Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value
Rat Calvery 1942 oral 350 —– 2,450 mg/m3 245 mg/m3
Mouse Calvery 1942 oral 350 —– 2,450 mg/m3 245 mg/m3
G. pig Calvery 1942 oral 200 —– 1,400 mg/m3 140 mg/m3
Rat Domingo et al. 1988 oral 1,100 —– 7,700 mg/m3 770 mg/m3
Mouse Domingo et al. 1988 oral 1,250 —– 8,750 mg/m3 875 mg/m3

Other animal data: It has been reported that 90 mg/m3 is the no observed adverse effect level (NOEL) for rat intratracheal fibrosis [Richards et al. 1989].

Human data: A 30-minute exposure to 4.8 mg/m3 has been reported to produce respiratory distress [Ferry 1974]. Exposure to 80 mg/m3 has caused nausea and coughing and 120 mg/m3 for 2 minutes has caused nose and upper respiratory system irritation [Cullumbine 1957].


1. Calvery HO [1942]. Trace elements in foods. Food Res 7:313-331.

2. Cullumbine H [1957]. The toxicity of screening smokes. J Royal Army Med Corps 103:119-122.

3. Domingo JL, Llobet JM, Paternain JL, Corbella J [1988]. Acute zinc intoxication. Vet Hum Toxicol 30(3):224-228.

4. Ferry JJ [1974]. Personal communication with area manager of industrial & environmental hygiene. General Electric Company, 1 River Road, Schenectady, NY 12345.

5. Karlsson N, Cassel G, Fangmark I, Bergman F [1986]. A comparative study of the acute inhalation toxicity of smoke from TiO2-hexachloroethane and Zn-hexachloroethane pyrotechnic mixtures. Arch Toxicol 59(3):160-166.

6. Marrs TC, Clifford WE, Colgrave HF [1983]. Pathological changes produced by exposure of rabbits and rats to smokes of hexachloroethane and zinc oxide. Toxicology Lett 19:247-252.

7. NIOSH [1976]. ZH14000. Zinc chloride. In: Registry of toxic effects of chemical substances, 1976 ed. Cincinnati, OH: 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. 76-191, p. 1228.

8. Richards RJ, Atkins J, Marrs TC, Brown RFR, Masek L [1989]. The biological and pathological changes produced by the intratracheal instillation of certain compounds of zinc-hexachloroethane smoke. Toxicology 54(1):79-88.