May 1994

Documentation for Immediately Dangerous To Life or Health Concentrations (IDLHs)

p-tert-Butyltoluene

CAS number: 98–51–1

NIOSH REL: 10 ppm (60 mg/m³) TWA, 20 ppm (120 mg/m³) STEL

Current OSHA PEL: 10 ppm (60 mg/m³) TWA

1989 OSHA PEL: 10 ppm (60 mg/m³) TWA, 20 ppm (120 mg/m³) STEL

1993-1994 ACGIH TLV: 1 ppm (6.1 mg/m³) TWA

Description of Substance: Colorless liquid with a distinct aromatic odor, somewhat like gasoline.

LEL: . . Unknown

Original (SCP) IDLH: 1,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the female rat 1-hour LC₅₀ of 934 ppm reported by Hine et al. [1954].

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:

Species

Reference

LC₅₀

(ppm)

LC_Lo

(ppm)

Time

Adjusted 0.5-hr

LC (CF)

Derived value

Rat

Mouse

Hine et al. 1954

934

734

248

165

248

-----

1 hr

2 hr

4 hr

8 hr

4 hr

1,168 ppm (1.25)

1,174 ppm (1.6)

496 ppm (2.0)

413 ppm (2.5)

496 ppm (2.0)

117 ppm

50 ppm

41 ppm

50 ppm

Other animal data: RD₅₀ (mouse), 360 ppm [Nielsen and Alarie 1982].

Human data: Giddiness and altered respiration have been reported in volunteers exposed to 160 ppm for 15 minutes [Hine et al. 1954].

Revised IDLH: 100 ppm

Basis for revised IDLH: The revised IDLH for p-tert-butyltoluene is 100 ppm based on acute inhalation toxicity data in humans [Hine et al. 1954].

REFERENCES:

1. Hine CH, Ungar H, Anderson HH, Kodama JK, Critchlow JK, Jacobsen NW [1954]. Toxicological studies on p-tertiary-butyltoluene. AMA Arch Ind Hyg Occup Med 9:227-244.

2. Nielsen GD, Alarie Y [1982]. Sensory irritation, pulmonary irritation, and respiratory stimulation by airborne benzene and alkylbenzenes: prediction of safe industrial exposure levels and correlation of their thermodynamic properties. Toxicol Appl Pharmacol 65:459-477.