Typical profile identification of pollution sources by polycyclic aromatic sulfur heterocycles

A semi-quantitative method has been developed for the determination of typical profiles of PASHs to identify the main sources of soil pollution. PASHs compounds selected in this study were 2,3-dimethylbenzothiophene, 6,7- dimethylbenzothiophene, naphto[1,2-b]thiophene, phenanthro[3,4-b]thiophene, 3-phenylbenzothiophene and 3-(naphthyl)benzothiophene. Extraction of soil samples was carried out by ultrasonication using a mixture of n-hexane and dichloromethane. Final analysis was performed by gas chromatography using a non-polar capillary column TR-5ms (60 m, 0.25 mm, 0.25 µm) and the detection by high resolution mass spectrometer with magnetic and electric sector using electronic impact ionization. The linear range of the standard curve prepared from contaminated soil was from 1.0 to 8.0 ngKg-1 (R2 >0.97). Limits of detection ranged from 0.13 ngKg-1 to 2.50 ngKg-1 . The developed analytical method was successfully applied to study the soil profiling polluted by mobile and fixed sources.