Pah calibration mix

Leaf dust. From the total number of collected birch leaves in each individual urban zone (surface area of ca. 250 cm² for each tree), 30 leaves were selected and placed in a sterile flask with 30 mL of deionized water and thoroughly mixed on the shaker at 200 rpm for 15 min. The leaves were scanned, and their area was determined. The PAHs of 10 mL of methylene chloride were extracted from the obtained solution. The PAHs were determined by high performance liquid chromatography (HPLC) using an Agilent 1260 system (USA) with the fluorescence detector. We evaluated PAHs from the List of Priority Pollutants [36 ]: acenaphthene, anthracene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[g,h,i]perylene, chrysene, dibenzo[a,h]anthracene, fluoranthene, fluorene, phenanthrene, and pyrene. The minimum detection limit for PAHs was 0.05 µg/kg. The recovery rate was 90%–97%. The PAH Calibration Mix (Merck, Germany) was used as a standard. The components were quantified by an absolute calibration curve method.
Road dust. An amount of 2 g of the sieved dust was taken from each of three replicate dust samples. The PAHs were extracted from these samples of road dust by 50 mL of methylene chloride and separated using the HPLC method that is described in the previous paragraph.

The PAHs were initially extracted from 2 g of road dust using 50 mL of methylene chloride and separated by high performance liquid chromatography (HPLC) using an Agilent 1260 system (USA) with the fluorescence detector. We analyzed 13 PAH types of the 16 that are presented in the Priority Pollutants List [36 ]: fluorene, acenaphthene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, and benzo[g,h,i]perylene. The detection limit for the PAHs in these samples which was acquired using the combination of PAH extraction and HPLC detection methods was 0.05 µg/kg. The recovery rates varied between 90 and 97%. The PAH Calibration Mix (Merck, Germany) was used as a standard. The components were quantified by an absolute calibration curve method.