MONITORING POLYCYCLIC AROMATIC COMPOUNDS IN ENVIRONMENTAL AND WORKPLACE SAMPLES USING CONVENTIONAL METHODS AND THE AMES MUTAGENICITY ASSAY OF THEIR NITRATED DERIVATIVES

• Published in: Polycyclic aromatic compounds 2008-11, Vol.28 (4-5), p.533-544
• Main Authors: Blackburn, Gary R., Bleicher, William T., Glidden, Stacy, Reinke, Gerald
• Format: Article
• Language: English
• Subjects: Ames Test; asphalt; biomonitoring; industrial hygiene; nitro-PAC; PAC
• ISSN: 1040-6638; 1563-5333
• DOI: 10.1080/10406630802374770

The development of sensitive methods for monitoring polycyclic aromatic compounds (PACs) has been a central focus of industrial hygiene studies in those industries where workers are exposed to petroleum oils, bitumen fumes or fuel combustion products. The work reported here focuses on one aspect of that effort-workplace monitoring of airborne PAC levels in the hot-mix asphalt paving industry. During the manufacture, transport, and roadway application of hot-mix asphalt (HMA), workers are exposed to low levels of bitumen fumes emanating from the hot product. Over the last twenty-five years, concerns about the health effects of these exposures have prompted numerous studies of the airborne levels of asphalt fumes in the workplace. By and large, these studies have shown that PAC exposures are extremely low-often below the detection limits of standard analytical techniques. For the present study, we have used standard industrial hygiene methods, together with a newer, biologically based assay called the Nitration Assay to measure relative ambient levels of fumes and/or PACs in various paving workplace settings. The latter assay was also used to test bitumen fumes generated in the laboratory by a new "microfuming" technique and to determine specific activities of the 16 PAHs designated by the US EPA as priority pollutants. The Nitration Assay takes advantage of two properties of 3-7-ring PACs: the ease with which they can be chemically nitrated and the high mutagenic potency of the nitrated products in the Ames Salmonella mutagenicity assay. Measurements of fumes and nitratable PAC levels on seven different hot-mix paving jobs showed reasonable correlations between the various methods, as well as patterns of exposure consistent with proximity to fume source.