determination of polycyclic aromatic hydrocarbon (pahs) in soil and plant samples by method of ultrasonic-coupled quechers and gas chromatography- mass spectroscopy

Abstract: environmental pollution from hazardous and toxic chemicals is one of the major problems facing the world today. persistent organic pollutants (pops) are a group of toxic substances among environmental pollutants. polycyclic aromatic hydrocarbons (pahs) are included in group of persistent organic pollutants due to chemical structure persistent and intrinsic resistance against biological and non-biological decomposition and in case of existence in food chain, polycyclic aromatic hydrocarbons are one of the most worrying indices and threats for living things. the use of kerosene as a herbicide in some vegetable fields in khuzestan province, including dezful city, leads to contamination of soil and vegetables grown in these fields, especially carrots. the current research aims to measure petroleum pollutant in soil and plant samples. increasing the concentration of kerosene significantly increases the polycyclic aromatic hydrocarbons in the soil and plants. in order to extract pahs and tphs in soil and plant samples, soxhlet extraction method and ultrasonic coupled extractors were used. gas chromatography - mass spectroscopy (gc-ms) was used to measure the amount of pahs. determination of heavy metals in the soil sample was performed using dissolution method with hydrofluoric acid and perchloric acid according to the standard with induced coupled plasma mass spectrometry. lead and cadmium were measured in plant samples by spectroscopic method of atomic absorption of graphite furnace after microwave digestion. in order to the clean-up of extracts and separate the analyte from the complex matrix, spe solid phase extraction was used using c18 cartridge in succulent extraction, as well as c18 cartridge and dmlle diffusion fluid microextraction in quechers method. considering the excessive absorption of pahs in carrots, it can be concluded that the use of kerosene in vegetable fields has increased the concentration of these compounds in vegetables. the results of this study show that the proposed method of ultrasonic-coupled quechers followed by dllme purification and gc-ms analysis has a very good ability to determine very small amounts of pahs in carrot and soil samples. according to the competency figures comparable to other methods, its good performance can be mentioned.