A gas chromatographic (GC) method for detection of polycyclic aromatic hydrocarbons (PAH) in rood asphalt and diesel engine emissions was evaluated. A photoionization detector with a low energy 8.3 electron volt ultraviolet lamp was used with a high resolution capillary column. Helium was used as the carrier gas with argon as the makeup gas. Gases were passed through water and oxygen scavengers. A standard was used that contained 16 PAH. Bulk asphalt from a road surface was diluted with methylene-chloride, centrifuged, and filtered, then diluted with methylene-chloride again and read by GC. Particulate diesel emissions were collected on a filter, extracted with methylene-chloride, and read by GC. The extract was also fractionated, evaporated, and analyzed for PAH using GC and a photoionization detector. Compared with liquid chromatographic methods, better precision was obtained using GC with the photoionization detector. Lowest detectable concentrations of pyrene (129000), benzo(b)fluorene (30777196), benz(a)anthracene (56553), benzo(a)pyrene (50328), and dibenz(a,h)anthracene (53703) were 0.02 micrograms per milliliter (microg/ml). For fluoranthene (206440) and chrysene (218019), the lowest detectable concentration was 0.03microg/ml. The author concludes that the technique is useful in analysis of PAH pollutants.
Division of Physical Sciences and Engineering, NIOSH, NTIS PB83-196-188, 19 pages, 7 references