Xylidine

CAS number: 1300–73–8 (mixed isomers)

NIOSH REL: 2 ppm (10 mg/m³) TWA [skin]

Current OSHA PEL: 5 ppm (25 mg/m³) TWA [skin]

1989 OSHA PEL: 2 ppm (10 mg/m³) TWA [skin]

1993-1994 ACGIH TLV: 0.5 ppm (2.5 mg/m³) TWA [skin], A2

Description of substance: Pale-yellow to brown liquid with a weak, aromatic, amine-like odor.

LEL: . . 1.0% (10% LEL, 1,000 ppm)

Original (SCP) IDLH: 150 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the mouse 7-hour LC₅₀ of 149 ppm [von Oettingen et al. 1947 cited by ACGIH 1971].

Short-term 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
Mice (2,4-)	von Oettingen et al. 1947	149	-----	7 hr	358 ppm (2.4)	36 ppm

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
Rabbit	Deichmann & Gerarde 1969	oral	-----	600	833 ppm	83 ppm
Rat	Treon et al. 1949	oral	-----	610	847 ppm	85 ppm
Rat (2,3-)	Vernot et al. 1977	oral	-----	930	1,292 ppm	129 ppm
Mouse (2,3-)	Vernot et al. 1977	oral	-----	1,070	1,486 ppm	149 ppm
Rat (2,4-)	Vernot et al. 1977	oral	-----	470	653 ppm	65 ppm
Mouse (2,4-)	Vernot et al. 1977	oral	-----	250	347 ppm	35 ppm
Rat (2,4-)	Lindstrom et al. 1969	oral	-----	1,259	1,749 ppm	175 ppm
Rat (2,5-)	Vernot et al. 1977	oral	-----	1,300	1,806 ppm	181 ppm
Mouse (2,5-)	Vernot et al. 1977	oral	-----	840	1,167 ppm	117 ppm
Rat (2,6-)	Vernot et al. 1977	oral	-----	1,230	1,708 ppm	171 ppm
Mouse (2,6-)	Vernot et al. 1977	oral	-----	710	986 ppm	99 ppm
Rat (2,6-)	Short et al. 1983	oral	-----	1,050	1,458 ppm	146 ppm
Rat (3,4-)	Vernot et al. 1977	oral	-----	810	1,125 ppm	113 ppm
Mouse (3,4-)	Vernot et al. 1977	oral	-----	710	986 ppm	99 ppm
Rat (3,5-)	Vernot et al. 1977	oral	-----	710	986 ppm	99 ppm
Mouse (3,5-)	Vernot et al. 1977	oral	-----	420	583 ppm	58 ppm

Human data: None relevant for use in determining the revised IDLH.

Revised IDLH: 50 ppm Basis for revised IDLH: The revised IDLH for xylidine is 50 ppm based on acute toxicity data in animals [Deichmann and Gerarde 1969; Treon et al. 1949; Vernot et al. 1977; von Oettingen et al. 1947]. This may be a conservative value due to the lack of relevant acute toxicity data for workers.

REFERENCES:

1. ACGIH [1971]. Xylidine. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 282-283.

2. Deichmann WB, Gerarde HW [1969]. Xylidine (aminodimethylbenzene). Toxicology of drugs and chemicals. New York, NY: Academic Press, Inc., p. 637.

3. Lindstrom HV, Bowie WG, Wallace WG, et al. [1969]. The toxicity and metabolism of mesidine and pseudodocumidine in rats. J Pharmacol Exp Ther 167:223. [From ACGIH [1991]. Xylidine. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 1743-1745.]

4. Short CR, King C, Sistrunk PW, Kerr KM [1983]. Subacute toxicity of several ring-substituted dialkylanilines in the rat. Fundam Appl Toxicol 3(4):285-292.

5. Treon JF, Deichmann WB, Sigmon HE, Wright H, Witherup SO, Heyro FF, Kitzmiller KV, Kelnan C [1949]. The toxic properties of xylidine and monomethylaniline. I. The comparative toxicity of xylidine and monomethyaniline when administered orally or intravenously to animals or applied upon their skin. J Ind Hyg Toxicol 31:1-18.

6. Vernot EH, MacEwen ID, Haun GG, Kinkead ER [1977]. Acute toxicity and skin corrosion data for some organic and inorganic compounds and aqueous solutions. Toxicol Appl Pharmacol 42(2):417-423.

7. von Oettingen WF, Neal PA, Sievers RF, Svirbely JL, Monaco AR, Horecker BL, Yagoda H, Sweeney TR, Peterson DC, Alford WC, Hauff VB, Gay H [1947]. Xylidine (c,c-dimethylaniline): its toxicity and potential dangers as compared with those of aniline and an appraisal of the potential hazards from its use in blending gasoline. NIH Bulletin 188:88.