Nitrotoluene (o-, m-, p-isomers)

CAS numbers: 88-72-2 (o-isomer), 99-08-1 (m-isomer), 99-99-0 (p-isomer)

NIOSH REL: 2 ppm (11 mg/m³) TWA [skin]

Current OSHA PEL: 5 ppm (30 mg/m³) TWA [skin]

1989 OSHA PEL: 2 ppm (11 mg/m³) TWA [skin]

1993-1994 ACGIH TLV: 2 ppm (11 mg/m³) TWA [skin]

Description of substance: Yellow liquids (o-, m-isomers) or a crystalline solid (p-isomer) with weak, aromatic odors.

LEL(o-isomer): 2.2% (10% LEL, 2,200 ppm)

Original (SCP) IDLH: 200 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on an analogy with nitrobenzene which has an IDLH of 200 ppm.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
o-isomer Rat	Vasilerko et al. 1978	oral	891	-----	1,094 ppm	109 ppm
o-isomer Mouse	Vasilerko et al. 1978	oral	970	-----	1,191 ppm	119 ppm
o-isomer Rabbit	Vasilerko et al. 1978	oral	1,750	-----	2,149 ppm	215 ppm
p-isomer Mouse	Back et al. 1972	oral	1,231	-----	1,512 ppm	151 ppm
p-isomer Rat	Vasilerko et al. 1978	oral	1,960	-----	2,407 ppm	241 ppm
p-isomer Rabbit	Vasilerko et al. 1978	oral	1,750	-----	2,149 ppm	215 ppm

Human data: It has been stated that nitrotoluene is only slightly toxic, especially in comparison with nitrobenzene [Linch 1974].

Revised IDLH: 200 ppm [Unchanged] Basis for revised IDLH: Based on acute oral toxicity data in animals [Back et al. 1972; Vasilerko et al. 1978] and an analogy to nitrobenzene [Linch 1974] which has an IDLH of 200 ppm, the original IDLH for nitrotoluene (200 ppm) is not being revised at this time.

REFERENCES:

1. Back KC, Thomas AA, MacEwen JD [1972]. Reclassification of materials listed as transportation health hazards. Wright-Patterson Air Force Base, OH: 6570th Aerospace Medical Research Laboratory, Report No. TSA-20-72-3, pp. A-310 to A-311.

2. Linch AL [1974]. Biological monitoring for industrial exposure to cyanogenic aromatic nitro and amino compounds. Am Ind Hyg Assoc J 35:426-432.

3. Vasilerko NM, Kovalenko EE, Batuzina TS [1978]. Experimental substantiation of hygienic concentrations of isomers of mononitrotoluenes in the air of the working zone. Gig Tr Prof Zabol 22(7):52 (in Russian).