Distribution and sources of polycyclic aromatic hydrocarbons in water and sediments of the Soltan Abad River, Iran

Distribution of the sixteen polycyclic aromatic hydrocarbons (PAHs) was detected in water and sediments of the Soltan Abad River. Liquid–liquid extraction was used for water samples, while PAHs in sediments were extracted using Soxhlet Extraction and finally analyzed by means of gas chromatography. Results showed that in water samples, the highest concentration was related to acenaphthene (3-ring PAH), whereas fluoranthene (4-ring PAH) was the most important pollutant in sediments. The mean concentrations of PAHs was the highest in autumn and the lowest in summer, in both water and sediment samples. Diagnostic ratios such as phenanthrene/anthracene and fluoranthene/pyrene were achieved to evaluate the emission sources of PAHs. These ratios indicated a pyrolytic source of PAHs for sediments, as well as a pyrolytic or pyrogenic origin for water samples (with a dominant pyrolytic input) in the study area.