CAS 95–53–4 O Toluidine Reagent Aromatic Odor With 99% Purity

Biochemical Reagent O-Toluidine With Purity Above 99%

Chem. Abstr. Serv. Reg. No.: 95–53–4 CAS

Name: 2-Methylbenzenamine Synonyms: 1-Amino-2-methylbenzene; 2-methylphenylamine; 2-amino-1-methylbenzene; 2-methyl-1-aminobenzene; 2-aminotoluene; ortho-aminotoluene; 2-methylaniline; ortho-methylaniline; ortho-methylbenzenamine; 2- tolylamine; ortho-tolylamine

O-Toluidine is the most widely studied of the aromatic amines reviewed in this Volume. Waste-water, air and urine samples have been analysed. The use of LC/MS and LC with electrochemical detection provides detection limits down to the nanomol level. ortho-Toluidine is one of the amines detected as a reduction product of azo dyes used as toy colourants. Table 1.1 presents selected methods of detection and quantification of ortho-toluidine in various matrices.

Occupational exposure

Occupational exposure to o-toluidine can occur by inhalation or skin contact during its production, or during the production of pigments, dyes and rubber chemicals manufactured from this chemical. Medical personnel and laboratory may be exposed when using o-toluidine for staining tissues (IARC, 2010).

From the US National Occupational Exposure Survey (1981–83) it was estimated that 30000 (including approximately 15500 women) workers, were potentially exposed to o-toluidine (NIOSH, 1990). But no estimates of the number of exposed workers in the European Union have been reported.

At a chemical plant in the former Soviet Union where o-toluidine was produced via reduction of o-nitrotoluene, workers were exposed to concentrations of o-toluidine in the air that generally exceeded the maximum permissible concentration by 2–7-fold. In a total of 215 air samples, the highest exposure levels were observed during distillation and extraction processes (25–28.6 mg/m3). Dermal exposures also were documented (Khlebnikova et al., 1970). Measurements in the 1940s in a US dye-production plant indicated that the concentration of o-Toluidine was < 0.5 ppm [2 mg/m3] in the workroom air and in the breathing zone of the workers, and < 0.3–1.7 mg/L in the urine of workers engaged in the production of thio-indigo (Ott & Langner, 1983). Exposure to o-Toluidine was also reported to occur in plants involved in dye-production in Italy (Rubino et al., 1982), Germany (Stasik, 1988), and the USA (New Jersey) (Delzell et al., 1989), but no data on exposure levels were provided.

Medical and laboratory personnel also are potentially exposed to o-toluidine, although air concentrations are reportedly low (EPA, 1984; Kauppinen et al., 2003).

Concentrations of o-toluidine in indoor air in plants producing rubber antioxidants or vulcanising rubber articles ranged up to several hundred µg/m3 and o-toluidine concentrations in post-shift urine samples were around 100 µg/L (Ward et al., 1991; Teass et al., 1993; Ward et al., 1996; Korinth et al., 2006).