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

CAS number: 3689–24–5

NIOSH REL: 0.2 mg/m3 TWA [skin]

Current OSHA PEL: 0.2 mg/m3 TWA [skin]

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.2 mg/m3 TWA [skin]

Description of substance: Pale-yellow liquid with a garlic-like odor.

LEL :. . Unknown

Original (SCP) IDLH: 35 mg/m3

Basis for original (SCP) IDLH: The chosen IDLH is based on the rat oral LD50 of 5 mg/kg [Lehman 1951 cited by ACGIH 1971]. No other useful data are available on which to base the IDLH.

Short-term exposure guidelines: None developed


Lethal concentration data:

SpeciesReferenceLC50LCLoTimeAdjusted 0.5-hr


Derived value
RatKimmerle & Klimmer 197438 mg/m3-----4 hr76 mg/m3 (2.0)7.6 mg/m3
MouseKimmerle & Klimmer 197440 mg/m3-----4 hr80 mg/m3 (2.0)8.0 mg/m3

Lethal dose data:





Adjusted LDDerived value
MouseKimmerle & Klimmer 1974oral22-----154 mg/m315 mg/m3
RabbitKimmerle &Klimmer 1974oral25-----175 mg/m318 mg/m3
DogKimmerle & Klimmer 1974oral5-----35 mg/m33.5 mg/m3
RatLehman 1951oral5-----35 mg/m3 3.5 mg/m3

Other animal data: It has been stated that TEDP is an organophosphate pesticide whose toxicity is similar to that of parathion [ACGIH 1991].

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

Revised IDLH: 10 mg/m3

Basis for revised IDLH: The revised IDLH for TEDP is 10 mg/m3 based on acute inhalation toxicity data in animals [Kimmerle and Klimmer 1974] and on an analogy with parathion [ACGIH 1991] which has a revised IDLH of 10 mg/m3.


1. ACGIH [1971]. TEDP (tetraethyl dithionopyrophosphate). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 244-245.

2. ACGIH [1991]. Sulfotep. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 1452-1454.

3. Kimmerle G, Klimmer OR [1974]. Acute and subchronic toxicity of sulfotep. Arch Toxicol 33:1-16.

4. Lehman AJ [1951]. Chemicals in foods: A report to the Association of Food and Drug Officials on current developments. Part II. Pesticides. Section II. Dermal Toxicity. Q Bulletin Assoc Food Drug Off U.S. 16(1):3-9.

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