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Dibutyl phthalate

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

CAS number: 84–74–2

NIOSH REL: 5 mg/m3 TWA

Current OSHA PEL: 5 mg/m3 TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 5 mg/m3 TWA

Description of Substance: Colorless to faint-yellow, oily liquid with a slight, aromatic odor.

LEL(@456 F): 0.5% (10% LEL(@456 F), 32,700 mg/m3)

Original (SCP) IDLH: 9,300 mg/m3

Basis for original (SCP) IDLH: Because dibutylphthalate has a very low toxicity, the available toxicological data contains no evidence of an IDLH for it. Therefore, the chosen IDLH is based on an analogy with dimethylphthalate, which has an IDLH of 9,300 mg/m3.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50 LCLo Time Adjusted 0.5-hrLC (CF) Derivedvalue
RatMouse Antonyuk and Aldyreva 1973Izmerov et al. 1982 4,250 mg/m325,000 mg/m3 ———- ?2 hr ?40,000 mg/m3 (1.6) ?4,000 mg/m3


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value

G. pig

Antonyuk 1963Sine 1993

Timofeevskaia et al. 1980







37,023 mg/m356,000 mg/m3

70,000 mg/m3

3,702 mg/m35,600 mg/m3

7,000 mg/m3

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



1. Antonyuk OK [1963]. About the toxicity of didodecylphthalate. Gig Tr Prof Zabol 17(11):51-52 (in Russian).

2. Antonyuk OK, Aldyreva MV [1973]. Substantiation of maximum permissible concentration of dibutyl phthalate in the air of industrial premises. Gig Tr Prof Zabol 17(8):26-30 (in Russian).

3. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 44.

4. Sine C, ed. [1993]. Dibutyl phthalate. In: Farm chemicals handbook ’93, p. C112.

5. Timofeevskaia LA, Ivanova NI, Baliniva ES [1980]. Toxicology of o-phthalic acid and esters and hygienic regimentation. Gig Tr Prof Zabol 24(3):25-27 (in Russian).