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Triphenyl phosphate

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

CAS number: 115–86–6

NIOSH REL: 3 mg/m3 TWA

Current OSHA PEL: 3 mg/m3 TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 3 mg/m3 TWA

Description of substance: Colorless, crystalline powder with a phenol-like odor.

LEL :. . Unknown

Original (SCP) IDLH*: No Evidence [*Note: “Effective” IDLH = 1,500 mg/m3 — see discussion below.]

Basis for original (SCP) IDLH: The available toxicological data contain no evidence of an IDLH for triphenyl phosphate. AIHA [1970] reported that concentrations of triphenyl phosphate aerosol high enough to produce acute toxic effects in man have not been achieved. For this draft technical standard, therefore, respirators have been selected on the basis of the assigned protection factor afforded by each device. However, for some particulate substances for which no evidence of an IDLH exists, the determination of allowable respiratory protection based on protection factors may result in the assignment of respirators for concentrations that are not likely to be encountered in the occupational environment. Therefore, for all such particulate substances it has been arbitrarily determined that only the “most protective” respirators are permitted for use in concentrations exceeding 500 ´ the OSHA PEL (500 ´ 3 mg/m3 is 1,500 mg/m3); only the “most protective” respirators are permitted for use in concentrations exceeding 1,500 mg/m3.

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value
Mouse Antonyuk 1974 oral 1,320 —– 9,240 mg/m3 924 mg/m3
Rat Hierholzer et al. 1957 oral 3,500 —– 24,500 mg/m3 2,450 mg/m3

Human data: Workers exposed to an average air concentration of 3.5 mg/m3 for as long as ten years showed no evidence of adverse clinical effects [Sutton et al. 1960].


1. AIHA [1970]. Triphenyl phosphate. In: Hygienic guide series. Am Ind Hyg Assoc J 31:388-390.

2. Antonyuk OK [1974]. Hygienic evaluation of plastificator triphenylphosphate, a component of polymer compositions. Gig Sanit 39(8):98-99 (in Russian).

3. Hierholzer K, Noetzel H, Schmidt L [1957]. Vergleichende toxikologische untersuchung von triphenylphosphat und trikresylphosphat. Arzneimittel-Forschung (Drug Research) 7:585-588.

4. Sutton WL, Terhaar CJ, Miller FA, Scherberger RF, Riley EC, Roudabush RL, Fassett DW [1960]. Studies on the industrial hygiene and toxicology of triphenyl phosphate. Arch Environ Health 1:33-46.