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NIOSH REL: 0.100 mg/m3 TWA
Current OSHA PEL: 0.050 mg/m3 TWA
1989 OSHA PEL: Same as current PEL
19931994 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.
Shortterm exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal dose data:
| LD50
(mg/kg) |
| |||||
| PbODog | Flury and Zernik 1935 | 1,400 | ||||
| PbC4H6O4Dog | Flury and Zernik 1935 | 300 | ||||
| PbCl2G. pig | Budavair 1989 | 1,500 | ||||
| Pb(NO3)2G.pig | Tartler 1941 | 500 | ||||
| Pb(CN)2Rat | NRC 1953 | 100 |
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 70kg 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/m3
Basis 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).] |
REFERENCES:
1. AIHA [1958]. Lead and its inorganic compounds. In: Hygienic guide series. Am Ind Hyg Assoc J 19:154155.
2. APHA [1943]. Occupational lead exposure and lead poisoning. New York, NY: American Public Health Association, pp. 1720.
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. 6871.
5. Flury F, Zernik F [1935]. Zusammenstellung der toxischen und letalen dosen für die gebräuchlichsten gifte und versuchstiere. Abder Hand Biol Arbeitsmethod 4:12891422 (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. 76191, p. 660.
7. NRC [1953]. ChemicalBiological 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/93T/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 125:273292
(in German).
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