Determination of Benzidine, Related Congeners, and Pigments in Atmospheric Paniculate Matter

Publisher Website
Google Scholar
Abstract
Methods for the determination of benzidine, related congeners, and pigments in atmospheric particulate matter, based on high performance liquid chromatography, are described. The methods are evaluated using National Bureau of Standards atmospheric particulate matter, as well as freshly collected particulate matter obtained in the vicinity of dyestuff manufacturing plants. Detection limits are approximately 0.5 ng/m3 for Pigment Yellow 12 and azobenzene; 1 ng/m3 for 3,3′-dimethylbenzidine, 3,3′- dimethoxybenzidine, and benzidine; and 0.1 ng/m3 for 3,3′-dichlorobenzidine and 4-aminobiphenyl (assuming an ambient paniculate level of 100 μg/m3). Recoveries are greater than 60%—except for benzidine, 3,3′-dimethylbenzidine, and 3,3'-dimethoxybenzidine which gave 30 to 40% recoveries at the 25 ng/m3 (25 μg/g) level and 50 to 70% recoveries at the 10 ng/m3 (100 μg/g) level in atmospheric paniculate matter. The method is especially useful as a qualitative method, since both the dependence of chromatographic response with electrochemical detector voltage and the retention time are indicators of component identity.