Occupational Exposure To O Tolidine PDF Download

Ortho-Toluidine (o-toluidine) is a high-production-volume chemical used in the manufacture of rubber chemicals, herbicide intermediates, dye intermediates, and some drugs like the local anesthetic prilocaine. o-Toluidine has been listed as a human carcinogen (Group 1)(IARC 2010, 2012) based on sufficient evidence of carcinogenicity from studies in both experimental animals and humans. In humans occupationally exposed to o-toluidine the urinary bladder is the major tumor site. Occupational exposure to o-toluidine can occur by inhalation or skin contact (IARC 2010) during its production, or during its use in the production of chemical intermediates. Measured o-toluidine in urine and/or as hemoglobin adducts in occupationally exposed workers provide evidence that o-toluidine is absorbed following inhalation exposure (Korinth et al. 2007, 2006, Ward et al. 1996, Jones et al. 2005). Exposure to o-toluidine can be demonstrated by detection of o-toluidine and its N-acetyl-metabolites in urine or of hemoglobin adducts of o-toluidine in blood (Brown et al. 1995, Ward et al. 1996, Teass et al. 1993). It can be assumed that urinary levels reflect recent exposure, while, because of the 120-day half-life of human red blood cells, hemoglobin adducts reflect cumulative exposure (Cheever et al. 1992; NTP, 2014).