o­Chlorobenzylidene malononitrile

IDLH Documentation

CAS number: 2698­41­1

NIOSH REL: 0.05 ppm (0.4 mg/m3) CEILING [skin]

Current OSHA PEL: 0.05 ppm (0.4 mg/m3) TWA

1989 OSHA PEL: 0.05 ppm (0.4 mg/m3) CEILING [skin]

1993­1994 ACGIH TLV: 0.05 ppm (0.39 mg/m3) CEILING [skin]

Description of Substance: White crystalline solid with a pepper­like odor.

LEL: . . Unknown

Original (SCP) IDLH: 2 mg/m3

Basis for original (SCP) IDLH: The chosen IDLH is based on the Army [1961] report that a 2­minute exposure to concentrations between 2 and 10 mg/m3 was considered "intolerable" by 6 of 15 persons. Grant [1974] reported that human volunteers have found concentrations greater than 10 mg/m3 to be extremely irritating, intolerable for more than 30 seconds because of burning and pain in the eyes and chest [Punte et al. 1963].

Short­term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:


Species

Reference
LC50

(ppm)
LCLo

(ppm)

Time
Adjusted 0.5-hr

LC (CF)
Derived

value
Rat

Mouse

Rabbit

G. pig
Ballantyne and Swanston 1978

Ballantyne and Swanston 1978

Ballantyne and Swanston 1978

Ballantyne and Swanston 1978
-----

-----

-----

-----
1,806 mg/m3

2,753 mg/m3

1,802 mg/m3

2,326 mg/m3
45 min

20 min

10 min

10 min
2,059 mg/m3 (1.14)

2,643 mg/m3 (0.96)

1,243 mg/m3 (0.69)

1,605 mg/m3 (0.69)
206 mg/m3

264 mg/m3

124 mg/m3

161 mg/m3


Other animal data: RD50(mouse), 4.08 mg/m3 [Alarie 1981].

Human data: It has been reported that median incapacitating concentrations range from 12 to 20 mg/m3 after about 20 seconds of exposure [U.S. Depts of Army and Air Force 1963] and that a 2­minute exposure to concentrations between 2 and 10 mg/m3 was considered "intolerable" by 6 of 15 persons [Army 1961]. In another study, 3 of 4 volunteers exposed to 1.5 mg/m3 for 90 minutes developed headaches and 1 volunteer developed slight eye and nose irritation; human volunteers have found concentrations greater than 10 mg/m3 to be extremely irritating and intolerable for more than 30 seconds because of burning and pain in the eyes and chest [Punte et al. 1963]. Exposures above 14 mg/m3 for 1 hour produced extreme irritation, erythema, and vesication of the skin of volunteers [Weigand 1969].

Revised IDLH: 2 mg/m3 [Unchanged]

Basis for revised IDLH: Based on acute inhalation toxicity data in human volunteers [Army 1961; Punte et al. 1963; U.S. Depts of Army and Air Force 1963; Weigand 1969], the original IDLH for o­chlorobenzylidene malononitrile (2 mg/m3) is not being revised at this time.


REFERENCES:

1. Alarie Y [1981]. Dose­response analysis in animal studies: prediction of human responses. Environ Health Perspect 42:9­13.

2. Army [1961]. U.S. Army, Chemical Corps Safety Directive No. 385­12. Safety guide for processing, filling, handling and decontamination of CS and CS1. Edgewood Arsenal, MD: CML C SD­385­12, p. 4.

3. Ballantyne B, Swanston DW [1978]. The comparative acute mammalian toxicity of 1­chloroacetophenone (CN) and 2­chlorobenzylidene malononitrile (CS). Arch Toxicol 40:75­95.

4. Grant WM [1974]. Toxicology of the eye. 2nd ed. Springfield, IL: C.C. Thomas, pp. 263­264.

5. Punte CL, Owens EJ, Gutentag PJ [1963]. Exposures to ortho­chlorobenzylidene malononitrile: controlled human exposures. Arch Environ Health 6:366­374.

6. U.S. Departments of the Army and Air Force [1963]. Military chemistry and chemical agents. Washington, DC: Army Technical Manual TM3­215; Air Force Manual AFM 355­7, December 1963.

7. Weigand DA [1969]. Cutaneous reaction to the riot control agent CS. Milit Med 134:437.
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