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Lead compounds (as Pb)

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

CAS number: 7439–92–1 (Metal)

NIOSH REL: 0.100 mg/m3 TWA

Current OSHA PEL: 0.050 mg/m3 TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.15 mg/m3 TWA

Description of substance: Varies

Original (SCP) IDLH*: 700 mg Pb/m3 [*Note: “Effective” IDLH = 400 mg Pb/m3 — see discussion below.]

Basis for original (SCP) IDLH: No data on acute toxicity are available concerning the physiological effects caused by the inhalation of lead and its inorganic compounds. AIHA [1958], however, reported that the severity of the health hazard for a brief exposure is only moderate [Fairhall 1957; APHA 1943]. If the IDLH were estimated from the rat intraperitoneal LDLO of 100 mg/kg for lead cyanide [NRC 1953] that was cited by NIOSH [1976], a value of 700 mg/m3 would be chosen as the IDLH. Using these data for lead cyanide rather than other data cited by NIOSH yields the most conservative estimate of the IDLH. Because of the assigned protection factor afforded by each device, however, 2,000 ´ the OSHA PEL of 0.2 mg Pb/m3 (i.e., 400 mg Pb/m3) is the concentration above which only the “most protective” respirators are permitted.

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value
PbODog Flury and Zernik 1935 oral —– 1,400 9,114 mg Pb/m3 911 mg Pb/m3
PbC4H6O4Dog Flury and Zernik 1935 oral —– 300 1,344 mg Pb/m3 134 mg Pb/m3
PbCl2G. pig Budavair 1989 oral —– 1,500 7,770 mg Pb/m3 770 mg Pb/m3
Pb(NO3)2G.pig Tartler 1941 oral —– 500 2,205 mg Pb/m3 221 mg Pb/m3
Pb(CN)2Rat NRC 1953 i.p. —– 100 560 mg Pb/m3 56 mg Pb/m3

Human data: It has been reported that 714 mg/kg of lead acetate (i.e., about 450 mg/kg of lead) is the lethal oral dose [Takahashi 1975]. [Note: An oral dose of 450 mg Pb/kg is equivalent to a 70-kg worker being exposed to 21,000 mg Pb/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 100 mg Pb/m3Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for lead compounds. The revised IDLH for lead compounds is 100 mg Pb/m3 based on acute oral toxicity data in humans [Takahashi 1975] and animals [Flury and Zernik 1935]. [Note: OSHA currently requires in 29 CFR 1919.1025 that workers be provided with and required to wear and use the “most protective” respirators in concentrations exceeding 100 mg Pb/m3 (i.e., 2,000 ´ the current OSHA PEL of 0.05 mg Pb/m3).]


1. AIHA [1958]. Lead and its inorganic compounds. In: Hygienic guide series. Am Ind Hyg Assoc J 19:154-155.

2. APHA [1943]. Occupational lead exposure and lead poisoning. New York, NY: American Public Health Association, pp. 17-20.

3. Budavari S, ed. [1989]. 5278. Lead chloride. In: The merck index. 11th edition. Rahway, NJ: Merck & Co., Inc., p. 5275.

4. Fairhall LT [1957]. Industrial toxicology. 2nd ed. Baltimore, MD: Williams & Wilkins Company, pp. 68-71.

5. Flury F, Zernik F [1935]. Zusammenstellung der toxischen und letalen dosen für die gebräuchlichsten gifte und versuchstiere. Abder Hand Biol Arbeitsmethod 4:1289-1422 (in German).

6. NIOSH [1976]. OG01750. Lead(II) cyanide. 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. 660.

7. NRC [1953]. Chemical-Biological Coordination Center: review. Vol. 5. Washington, DC: National Academy of Sciences, National Research Council, p. 27.

8. Takahashi A [1975]. Problems of hygiene maintenance for food coming into contact with rubber and plastics products. Nippon Gomu Kyokaishi 48(9):537 [Translated by Inglis EA [1976]. Int Polymer Sci Tech 3(1):T/93-T/105.]

9. Tartler G [1941]. Die akute bleivergiftung. Ein experimenteller beitrag zur klärung der frage der giftigkeit von bleiverbindungen in quantitativen versuchen. Arch Hyg Bakteriol 125:273-292 (in German).