Use of the phenanthrene to benzo(e)pyrene ambient air ratio as an indicator for the source of polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAH) are emitted by many industrial, domestic and natural sources. In 1990, the principal sources of PAH for the Province of Quebec were primary aluminum smelters (858 t), residential heating with wood (162 t), forest fires (148 t) and transportation (33 t). A sampling program was developed to measure PAH levels in ambient air at different locations influenced by these sources. The highest concentrations of PAH in ambient air (470 ng/m{sup 3} geometric mean) were measured near primary aluminum smelters using Horizontal Stud Soederberg technology. Areas influences by wood heating (157 ng/m{sup 3} winter geometric mean) and transportation (80 ng/m{sup 3} geometric mean) had lower total PAH concentrations. Ratios of ambient air concentration for phenanthrene/benzo(e)pyrene were lower in samples collected in the surroundings of the primary aluminum smelters (7--14), whereas high ratios were observed for residential heating with wood and transportation (20--45). The use of this ratio was found to be a good indicator for PAH originating from primary aluminum smelters.