Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to page options Skip directly to site content

Tetramethyl lead (as Pb)

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

CAS number: 75–74–1

NIOSH REL: 0.075 mg/m3 TWA [skin]

Current OSHA PEL: 0.075 mg/m3 TWA [skin]

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.15 mg/m3 TWA [skin]

Description of substance: Colorless liquid (unless dyed red, orange, or blue) with a fruity odor.

LEL: . . Unknown

Original (SCP) IDLH: 40 mg Pb/m3

Basis for original (SCP) IDLH: The chosen IDLH is based on an analogy with tetraethyl lead which has an IDLH of 40 mg Pb/m3.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50 LCLo Time Adjusted 0.5-hr


Derived value
Mouse Castellino et al.1963 40,800 mg/m3 ----- 30 min 31,626 mg Pb/m3 (1.0) 3,163 mg Pb/m3
Rat Cremer &Calloway 1961 8,870 mg/m3 ----- 30 min 6,876 mg Pb/m3 (1.0) 688 mg Pb/m3
Mouse Marhold 1986 ----- 8,500 mg/m3 30 min 6,589 mg Pb/m3 (1.0) 659 mg Pb/m3

Lethal dose data:

Species Reference Route LD50




Adjusted LD Derived value

G. pig


Akatsuka 1973

Gekkan Yakuji 1980

Magistretti et al. 1963










130 mg Pb/m3

591 mg Pb/m3

570 mg Pb/m3

13 mg Pb/m3

59 mg Pb/m3

57 mg Pb/m3

Other animal data: It has been reported that signs of acute tetramethyl lead intoxication in rats were similar to that seen after acute poisoning with tetraethyl lead [ACGIH 1991].

Human data: None relevant for use in determining the revised IDLH.

Revised IDLH: 40 mg Pb/m3 [Unchanged]

Basis for revised IDLH: Based on acute inhalation toxicity data in animals [Castellino et al. 1963; Cremer and Calloway 1961; Marhold 1986], a value of 150 mg Pb/m3 (i.e., 2,000 times the NIOSH REL) would have been appropriate for tetramethyl lead. However based on an analogy to tetraethyl lead which has a revised IDLH of 40 mg Pb/m3, the original IDLH for tetramethyl lead (40 mg Pb/m3) is not being revised at this time


1. ACGIH [1991]. Tetramethyl lead. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 1521-1523.

2. Akatsuka K [1973]. Tetraalkyl lead poisoning. Sangyo Igaku (Japanese Journal of Industrial Health) 15:3-66.

3. Castellino N, Rossi A, Mole R [1963]. Miscellanea: toxicity of tetramethyl lead solutions to mice and rabbits. Brit J Ind Med 20:63-65.

4. Cremer JE, Calloway S [1961]. Further studies on the toxicity of some tetra and trialkyl lead compounds. Brit J Ind Med 18:277-282.

5. Gekkan Yakuji (Pharmaceuticals Monthly) [1980]; 22(3):455-459 (in Japanese).

6. Magistretti M, Zurlo N, Scollo F, Pacillo D [1963]. Tossicita comparata del piombo tetra-etile e del piombo tetra-metile. Med Lav 54:486-495 (in Italian).

7. Marhold J [1986]. Prehled Prumyslove Toxikologie, Organicke Latky. Prague, Czechoslovakia: Avicenum, p. 1258 (in Czechoslovakian).