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Mercury compounds [except (organo) alkyls] (as Hg)
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 7439–97–6 (Metal)
NIOSH REL: Hg Vapor: 0.05 mg/m3 TWA [skin];
Other: 0.1 mg/m3 CEILING [skin]
Current OSHA PEL: 0.1 mg/m3 CEILING
1989 OSHA PEL: Hg Vapor: 0.05 mg/m3 CEILING [skin];
Other non-alkyl compounds: 0.1 mg/m3 CEILING [skin]
1993-1994 ACGIH TLV: Hg Vapor: 0.05 mg/m3 TWA [skin];
Aryl & inorganic compounds: 0.1 mg/m3 TWA [skin]
Description of substance: Varies
Original (SCP) IDLH: 28 mg Hg/m3
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] and AIHA [1966] that “severe damage has been produced in the kidneys, liver, brain, heart, lungs, and colon of rabbits exposed for a single 4-hour period to mercury vapor at an average concentration of 28.8 mg/m3; mild damage to most of these organs occurred from 1 hour of exposure [Ashe et al. 1953].”
Existing short-term exposure guidelines: National Research Council [NRC 1984] Emergency Exposure Guidance Levels (EEGLs):
24-hour EEGL: 0.2 mg/m3
ACUTE TOXICITY DATA:
Lethal concentration data:
| Species | Reference | LC50 | LCLo | Time | Adjusted 0.5-hrLC (CF) | Derived value |
|---|---|---|---|---|---|---|
| Hg Rabbit | Ashe et al. 1953 | —– | 29 mg/m3 | 30 hr | 113 mg Hg/m3 (3.91) | 11 mg Hg/m3 |
Lethal dose data:
| Species | Reference | Route | LD50(mg/kg) | LDLo(mg/kg) | Adjusted LD | Derived value |
|---|---|---|---|---|---|---|
| Hg2Cl2Rat | Worthing 1991 | oral | 210 | —– | 1,250 mg Hg/m3 | 125 mg Hg/m3 |
| HgCl2H2NRat | Trakhtenberg et al. 1981 | oral | 86 | —– | 482 mg Hg/m3 | 48 mg Hg/m3 |
| HgCl2H2NMouse | Trakhtenberg et al. 1981 | oral | 68 | —– | 381 mg Hg/m3 | 38 mg Hg/m3 |
Other animal data: Severe damage has been produced in the kidneys, lungs, and colon of rabbits exposed for a single 4-hour period to mercury vapor at an average of 28.8 mg/m3; mild damage to most of the organs occurred after 1 hour of exposure [Ashe et al. 1953].
Human data: None relevant for use in determining the revised IDLH.
| Revised IDLH: 10 mg Hg/m3Basis for revised IDLH: The revised IDLH for mercury compounds [except mercury (organo) alkyls] is 10 mg Hg/m3 based on acute inhalation toxicity data in animals [Ashe et al. 1953]. |
REFERENCES:
1. AIHA [1966]. Mercury and its inorganic compounds (revised 1966). In: Hygienic guide series. Am Ind Hyg Assoc J 27:310-313.
2. Ashe WF, Largent EJ, Dutra FR, Hubbard DM, Blackstone M [1953]. Behavior of mercury in the animal organism following inhalation. AMA Arch Ind Hyg Occup Med 7:23-24.
3. NRC [1984]. 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. 89-94.
4. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1094.
5. Trakhtenberg EM, Kozshun NN, et al. [1981]. New data on toxicity of inorganic compounds of mercury. Gig Tr Prof Zabol 25(7):27-30 (in Russian).
6. Worthing CR, ed. [1991]. Mercurous chloride. In: The pesticide manual. A world compendium. 9th ed. Farnham, Surrey, United Kingdom: The British Crop Protection Council, p. 552.