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Arsenic (inorganic compounds, as As)
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number 7440-38-2 (Metal)
NIOSH REL 0.002 mg As/m3 15-minute CEILING; NIOSH considers inorganic arsenic compounds to be potential occupational carcinogens as defined by the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL: 0.010 mg As/m3 TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.01 mg As/m3 TWA, A1
Description of substance: Varies
Original (SCP) IDLH: 100 mg As/m3
Basis for original (SCP) IDLH: The chosen IDLH is based on the cat 1-hour LCLO of 100 mg/m3 for arsenic trichloride [Flury 1921 cited by NIOSH 1976].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
| Species | Reference | LC50 | LCLo | 0.5-hr Time | Adjusted LC (CF) | Derived Value |
|---|---|---|---|---|---|---|
| AsCl3 | ||||||
| Cat | Flury 1921 | —– | 100 mg/m3 | 1 hr | 52 mg As/m3 (1.25) | 5.2 mg As/m3 |
| Cat | Spector 1955 | —– | 200 mg/m3 | 20 min | 79 mg As/m3 (0.96) | 7.9 mg As/m3 |
| Mouse | Spector 1955 | —– | 338 ppm | 10 min | 726 mg As/m3 (0.69) 73 | mg As/m3 |
Lethal dose data:
| Species | Reference | Route | LD50(mg/kg) | LDLo(mg/kg) | Adjusted LD | Derived Value |
|---|---|---|---|---|---|---|
| Rat | Davydova et al. 1987 | oral | 763 | —– | 5,341 mg As/m3 | 534 mg As/m3 |
| Mouse | Davydova et al. 1987 | oral | 145 | —– | 1,015 mg As/m3 | 102 mg As/m3 |
| Ca3(AsO4)2 | ||||||
| Rat | Lehman 1951 | oral | 20 | —– | 53 mg As/m3 | 5.3 mg As/m3 |
| Mouse | MacEwen and Vernot 1972 | oral | 794 | —– | 2,090 mg As/m3 | 209 mg As/m3 |
| Rabbit | Muehlberger 1930 | oral | 50 | —– | 132 mg As/m3 | 13 mg As/m3 |
| Dog | Perkow 1971/1976 | oral | 38 | —– | 100 mg As/m3 | 10 mg As/m3 |
| Pb3(AsO4)2 | ||||||
| Rabbit | Muehlberger 1930 | oral | 75 | —– | 88 mg As/m3 | 8.8 mg As/m3 |
Human data: None relevant for use in determining the revised IDLH.
| Revised IDLH: 5 mg As/m3Basis for revised IDLH: The revised IDLH for inorganic arsenic compounds is 5 mg As/m3 based on acute inhalation toxicity data in animals [Flury 1921; Spector 1955]. This may be a conservative value due to the lack of relevant acute toxicity data for workers. [Note: NIOSH recommends as part of its carcinogen policy that the “most protective” respirators be worn for inorganic arsenic compounds at concentrations above 0.002 mg As/m3. OSHA currently requires in 29 CFR 1919.1018 that workers be provided with and required to wear and use the “most protective” respirators in concentrations exceeding 20 mg As/m3 (i.e., 2,000 x the PEL).] |
REFERENCES:
- Davydova VE, Neizuestnova EM, et al. [1987]. Toxicity of metallic arsenic. Gig Tr Prof Zabol 31(12):58 (in Russian).
- Flury F [1921]. Arsentrichlorid. In: Uber kampfgasvergiftungen. IX. Lokal reizende arsenverbindungen. Zeit Ges Exp Med 13:527-528 (in German).
- Lehman AJ [1951]. Chemicals in foods: a report to the Association of Food and Drug Officials on current developments. Part II. Pesticides. Q Bulletin Assoc Food Drug Off U.S. 15(4):122-125.
- MacEwen JD, Vernot EH [1972]. Toxic Hazards Research Unit annual technical report: 1972. Wright-Patterson Air Force Base, OH: Aerospace Medical Research Laboratory, Report AMRL-TR-72-62.
- Muehlberger CW [1930]. Toxicity studies of fluorine insecticides. J Pharmacol Exp Ther 39:246-248.
- NIOSH [1976]. CG17500. Arsenic chloride. In: Registry of toxic effects of chemical substances (RTECS) 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. 126.
- Perkow W [1971/1976]. Wirksubstanzen der Pflanzenschytz and Schadlingsbekampfungsmittel. Berlin, Germany: Verlag Paul Parey (in German).
- Spector WS, ed. [1955]. Handbook of toxicology. Vol. 1. Acute toxicities of solids, liquids and gases to laboratory animals. Philadelphia, PA: W.B. Saunders Co., pp. 324-325.