Assessment of Reliability when Using Diagnostic Binary Ratios of Polycyclic Aromatic Hydrocarbons in Ambient Air PM₁₀

Abstract

The reliability of using diagnostic binary ratios of particulate carcinogenic polycyclic aromatic hydrocarbons . No significant differences between day and night were found for any of the diagnostic binary ratios of PAHs, which indicates that the photodecomposition process is of minor importance in terms of PAH reduction. Interestingly, comparatively high values of COD for An/(An + Phe) in PM10 collected from sites with heavy traffic and in residential zones underline the influence of heterogeneous reactions triggered by oxidising gaseous species from vehicular exhausts. Therefore, special attention must be paid when interpreting the data of these diagnostic binary ratios, particularly for cases of low-molecular-weight PAHs.

Ambient and Indoor PM10 and PM10-bound PAHs around the Vicinity of an Industrial Estate in Rayong, Thailand: Concentration and Source Identification

“…The diagnostic ratios of PAHs were applied to classify and categorize pollution emission sources for ambient and indoor environment. Additionally, it is a simple and convenient approach for classification of atmospheric PAHs in order to provide a broad comprehensive perspective of source identification [38]. Anyhow, the chemical reaction with other air pollutants should be concerned, especially oxidizing gaseous species from vehicular exhaust.…”

“…Anyhow, the chemical reaction with other air pollutants should be concerned, especially oxidizing gaseous species from vehicular exhaust. The heterogeneous reactions between oxidizing gaseous species (ozone, NO3/N2O5 and OH radicals) from vehicular exhaust and LMW PAHs were mainly intended to reduce the concentrations of AN and PT [38]. Correspondingly, the source categorization of PAHs by using the binary ratios of AN/(AN+PT) might affect the alteration of AN/(AN+PT) ratios, especially the high traffic areas.…”