Abstract
Polycyclic aromatic hydrocarbons (PAHs) and selected nitrated derivatives (NPAHs) in air were determined at two sites, El Dokki (a traffic site) and El Teppen (an industrial site) in Greater Cairo, Egypt, during the winter and summer seasons. The sites were selected to represent areas with different activities of Greater Cairo. The concentrations of fifteen PAHs having two to six rings were determined by using HPLC with florescence detection, while the concentrations of two NPAHs, 1-nitropyrene (1-NP) and 6-nitrocrysene (6-NC), were determined using HPLC with chemilumencence detection. Both the PAH and NPAH concentrations in El Teppen were higher than those in El Dokki. The total average concentrations of the fifteen PAHs over the investigated sites were 45.98 pmol m
−3 in El Dokki and 77.01 pmol m
−3 in El Teppen. All PAH and NPAH concentrations were higher in winter than in summer. The total average concentration of PAHs ranged from 21.9 pmol m
−3 in summer to 63.74 pmol m
−3 in winter. PAHs having four to six rings were the predominant compounds in particulate matters. The total average concentrations of the two NPAHs (1-NP and 6-NC) were 30.2 and 12.4 fmol m
−3, respectively, in El Dokki, and 39.5 and 15.6 fmol m
−3 respectively, in El Teppen. The total average concentrations of 1-NP and 6-NC were 36.99 and 15.43 fmol m
−3, respectively, in winter, and 29.76 and 10.56 fmol m
−3, respectively, in summer. These concentrations were compared with those of several cities in Asia that have been undergoing rapid economic and industrial development. The major sources and secondary reactions of PAHs and NPAHs were estimated based on the [NPAH]/[PAH] and [PAH]/SPM ratios.
► In this report, PAHs and selected NPAHs were sampled from two sites in Egypt.
► The seasonal concentration differences at both sites were investigated.
► The measured concentrations were compared with other different sites in Asia.
► Major sources and secondary reactions of PAHs and NPAHs were identified.