Assessment of pollution, and determining potential sources of polycyclic aromatic hydrocarbons (PAHs) in street dust of Kermanshah Metropolis

Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic pollutants composed of two or more benzene rings. These compounds have attracted widespread attention due to their high carcinogenicity and mutagenicity in humans. In this study, 21 street dust samples were collected from various land uses in Kermanshah to investigate pollution and potential sources of PAHs. The samples were analyzed using gas chromatography-mass spectrometer (ICP-MS) after preparation. Also, in order to accurate identification of pollution sources, isomeric ratios were used. The results showed that all 16 PAH compounds identified by the United States Environmental Protection Agency (USEPA) as dangerous carcinogenic compounds are present in the street dust of Kermanshah metropolis. The concentration of total PAHs varies from 22.8 to 2820.98 μg / kg dry weight, with an average concentration of 1140.79 μg / kg. In addition, the toxic equivalency quotient (TEQ) in street dust samples of Kermanshah metropolis ranges from 18.54 μg / kg to 196.64 μg / kg, indicating the difference in concentration and toxicity of these compounds in different parts of the city. The results also show that the potential risk of carcinogenicity in adults and children through dermal contact is greater than direct ingestion and respiration pathways. In general, considering the isomeric ratios and principal component analysis, the combustion of fossil fuels, oil products and emissions from vehicles and traffic are the most important sources of PAHs in Kermanshah metropolis.