NIOSH logo and tagline

Benzyl chloride

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

CAS number: 100–44–7

NIOSH REL: 1 ppm (5 mg/m3) 15­minute CEILING

Current OSHA PEL: 1 ppm (5 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993­1994 ACGIH TLV: 1 ppm (5.2 mg/m3) TWA

Description of Substance: Colorless to slightly yellow liquid with a pungent, aromatic odor.

LEL: . . . 1.1% (10% LEL, 1,100 ppm)

Original (SCP) IDLH: 10 ppm

Basis for original (SCP) IDLH: Very little data are available on the acute effects of exposure to benzyl chloride. ACGIH [1971] reported that in 1 minute an exposure to 16 ppm is intolerable to man [Flury and Zernik 1931]. ILO [1972] reported that 20 ppm will render the atmosphere irrespirable in 1 minute. ILO [1971] reported that 50 to 100 mg/m3 (10 to 19 ppm) immediately causes weeping and twitching of the eyelids, while 160 mg/m3 (30 ppm) causes effects that are intolerable to the eyes and nasal mucous membranes. Based on this data, an IDLH of 10 ppm is assumed in order to avoid difficulties in escape in the event of respirator failure.

Short­term exposure guidelines: None developed


Lethal concentration data:

SpeciesReferenceLC50(ppm)LCLo(ppm)TimeAdjusted 0.5-hrLC (CF)Derivedvalue



IARC 1976IARC 1976

NIOSH 1978





2 hr2 hr

8 hr

240 ppm (1.6)128 ppm (1.6)

950 ppm (2.5)

24 ppm13 ppm

95 ppm


Other animal data: RD50 (mouse), 17 ppm [DeCeaurriz et al. 1981].

Human data: It has been reported that an exposure to 16 ppm for 1 minute is intolerable [Flury and Zernik 1931]. It has also been reported that 10 to 19 ppm immediately causes weeping and twitching of the eyelids [ILO 1971].



1. ACGIH [1971]. Benzyl chloride. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 24.

2. DeCeaurriz JC, Micillino JC, Bonnet P, Guenier JP [1981]. Sensory irritation caused by various industrial airborne chemicals. Toxicol Lett 9(2):137­143.

3. Flury F, Zernik F [1931]. Sch@dliche gase d@mpfe, nebel, rauch­ und staubarten. Berlin, Germany: Verlag von Julius Springer, p. 339 (in German).

4. IARC [1976]. IARC monographs on the evaluation of the carcinogenic risk of chemicals to man: benzyl chloride. Vol. 11. Lyon, France: World Health Organization, International Agency for Research on Cancer, p. 217.

5. ILO [1971]. Benzyl chloride. In: Encyclopaedia of occupational health and safety. 2nd ed. Vol. I (A­K). Geneva, Switzerland: International Labour Office, pp. 169­170.

6. ILO [1972]. Toluene and derivatives. In: Encyclopaedia of occupational health and safety. Vol. II (L­Z). 2nd ed. Geneva, Switzerland: International Labour Office, pp. 1414­1415.

7. NIOSH [1978]. NIOSH criteria for a recommended standard: occupational exposure to benzyl chloride. Cincinnati,OH: U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 78­182.