NIOSH logo and tagline

Ketene

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

CAS number: 463–51–4

NIOSH REL: 0.5 ppm (0.9 mg/m3) TWA, 1.5 ppm (3 mg/m3) STEL

Current OSHA PEL: 0.5 ppm (0.9 mg/m3) TWA

1989 OSHA PEL: 0.5 ppm (0.9 mg/m3) TWA, 1.5 ppm (3 mg/m3) STEL

1993-1994 ACGIH TLV: 0.5 ppm (0.86 mg/m3) TWA, 1.5 ppm (2.6 mg/m3) STEL

Description of substance: Colorless gas with a penetrating odor.

LEL: . . Unknown

Original (SCP) IDLH*: Unknown [*Note: “Effective” IDLH = 25 ppm — see discussion below.]

Basis for original (SCP) IDLH: No data on acute inhalation toxicity are available on which to base an IDLH for ketene. For this draft technical standard, therefore, the respirators have been selected on the basis of the assigned protection factor afforded by each device up to 50 ´ the OSHA PEL of 0.5 ppm (i.e., 25 ppm); only the “most protective” respirators are permitted for use in concentrations exceeding 25 ppm.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal concentration data:

Species Reference LC50(ppm) LCLo(ppm) Time Adjusted 0.5-hrLC (CF) Derived value
Mouse Mendenhall & Stokinger 1959 17 —– 10 min 12 ppm (0.69) 1.2 ppm
Mouse Treon et al. 1949 —– 23 30 min 23 ppm (1.0) 2.3 ppm
Rabbit Treon et al. 1949 —– 53 2 hr 85 ppm (1.6) 8.5 ppm
G. pig Treon et al. 1949 —– 53 2 hr 85 ppm (1.6) 8.5 ppm
Cat Treon et al. 1949 —– 750 10 min 518 ppm (0.69) 52 ppm
Monkey Treon et al. 1949 —– 200 10 min 138 ppm (0.69) 14 ppm
Mouse Treon et al. 1949 —– 50 10 min 35 ppm (0.69) 3.5 ppm
Rabbit Treon et al. 1949 —– 1,000 10 min 690 ppm (0.69) 69 ppm

Human data: It has been stated that 5 ppm is the lowest concentration productive of a clinically relevant physiologic response [Stokinger 1960].

REFERENCES:

1. Mendenhall RM, Stokinger HE [1959]. Tolerance and cross-tolerance development to atmospheric pollutants ketene and ozone. J Appl Physiol 14:923-926.

2. Stokinger HE [1960]. Toxicologic interactions of mixtures of air pollutants. Review of recent developments. Int J Air Pollut 2:313-326.

3. Treon JF, Sigmon H, Kitzmiller KV, Heyroth FF, Younker WJ, Cholak J [1949]. Physiologic response of animals exposed to airborne ketene. J Ind Hyg Toxicol 31:209-219.