Dichlorobenzidine pigment production

Emissions of dichlorobenzidine, chloroaniline, cuprous chloride and more during pigment production (17-20%)... 

Exposures of Children. There is no available information on exposme of children to 3,3 -dichlorobenzidine (or products derived from the compoimd). The compound has a very limited distribution and is not present in consumer goods (other than in insoluble pigmented forms). Thus, there is... 

Analytical identification of monoazo colorants and the other decomposition products requires effective (analytical) methods of concentration, which is made possible by high performance liquid chromatography (HPLC). Prior to HPLC analysis, the pigmented medium was extracted for 20 hours with toluene in a soxhlet extractor. These analytical methods also showed that above 240°C, especially after prolonged exposure of the pigmented polymer material to heat, dichlorobenzidine (DCB) is also formed. 

Studies investigating the bioavailability of P.Y.17 in rats, applied not only orally but also by inhalation, in no case showed the presence of any cleavage product of the pigment (e.g., 3,3-dichlorobenzidine or metabolites) in the urine or blood of the animals [31]. Similar studies were carried out with P.Y.13 and 174 [32], Recently the non-bioavailability of 3,3 -dichlorobenzidine from P.Y.13 and P.Y.17 was confirmed by means of molecular dosimetry for hemoglobin and DNA adducts [33]. 

Source Benzidine can enter the environment by transport, use, and disposal, or by dyes and pigments containing the compound. A photodegradation product of 3,3 -dichlorobenzidine. 

Dichlorobenzidine is a gray-to-purple colored crystalline solid. It changes from a solid to a gas very slowly. 3,3 -Dichlorobenzidine salt, the major form in actual use, is a stable, ofif-white colored crystalline solid that does not evaporate. Neither 3,3 -dichlorobenzidine nor its salt occur naturally in the environment. They are manufactured for use in the production of pigments for printing inks, textiles. 

Dichlorobenzidine is used primarily in the production of yellow, and some red and orange pigments for the printing ink, textile, paper, paint, rubber, plastic, and related industries (EPA 1979a). As of 1983,... 

Dichlorobenzidine does not naturally oceur in the environment (lARC 1982a). 3,3 -Diehlorobenzidine was not detected in ambient air of two dyestuff produetion plants at detection limits of 5 (Narang et al. 1982) and 0.1 ng/m (Riggin et al. 1983). More reeent data on occupational exposure levels indieate the presence of levels 0.6-2.5 g/m in 3,3 -diehlorobenzidine production and pigment manufaeturing plants in Germany (DCMA 1989). 

No uses of 3,3 -dichlorobenzidine in commonplace consumer products are known. In the past, the general public may have been exposed to minute amounts of 3,3 -dichlorobenzidine during the use of pressurized spray containers of paints, lacquers, and enamels containing traces of benzidine yellow, a pigment derived... 

Exposure Levels in Humans. It has been speculated that the 1974 OSHA regulations have reduced workplace air levels of 3,3 -dichlorobenzidine (CPMA 1998). However, it would be important to conduct exposure studies to monitor air levels in the workplace to confirm this premise. The need for more information on the extent of air, water, and soil contamination by industrial plant emissions or waste sites eontaining 3,3 -dichlorobenzidine continues. There is httle information on exposure of children to 3,3 -diehlorobenzidine (or products derived from the compoimd). The compound has a very limited distribution and is not present in consumer goods (other than in insoluble pigmented forms). This information is necessary for assessing the need to conduct health studies on these populations. 

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