Recent studies have indicated that sewer systems and landfills contain polychlorinated biphenyls (PCBs). In this study, 18 surface soil samples were collected from five areas near wastewater treatment plants and landfills to investigate PCB levels. The observed PCB congener numbers and levels in the samples varied. The total PCB values were 5558 +/- 2856 pg g(-1) dry weight (dw) (Sigma 61PCB) for the marine outfall of the Buski Pretreatment Plant (Bursa Water and Sewerage Administration), 5386 +/- 1627 pg g(-1) dw (Sigma 45PCB) for the Hamitler Landfill Area, 3901 +/- 281 pg g(-1) dw (Sigma 35PCB) for the Western Wastewater Treatment Plant, 1824 +/- 448 pg g(-1) dw (Sigma 42PCB) for the Yesil Cevre Wastewater Treatment Plant, and 725 +/- 220 pg g(-1) dw (Sigma 17PCB) for the Eastern Wastewater Treatment Plant. These results show that the soils near the treatment plants were not completely contaminated by PCBs. At the sampling sites, with the biphenyls between 2 and 7 chlorine molecules and in particular, an abundance of homologue groups with 3, 4, and 5 chlorines were found. Moreover, dioxin-like PCBs (PCB#77, 81, 105, 114, 118, 123, and 126) were detected in all samples.

This study was carried out to investigate the concentrations and potential sources of the polycyclic aromatic hydrocarbons (PAHs) in sludge of 14 wastewater treatment plants (WWTPs). Sludge samples were collected from 2 municipal WWTPs, 11 industrial WWTPs, and 1 sanitary landfill leachate treatment plant within the city of Bursa, Turkey during the summer of 2008. Ultrasonication was applied for extraction and gas chromatography–mass spectrometry was used to analyze the PAH contents of the samples. Twelve of the 16 EPA-listed PAH compounds were determined. Total PAH concentrations (∑12 PAHs) determined in all of the sludge samples ranged from 1,781 to 19,866 μg/kg dry matter (dm). The sum of 8 of the 11 EU PAHs varied between 1,481 and 17,314 μg/kg dm, and 3 of the samples exceeded the proposed EU limit for land application. One of the automotive industry sludges contained the highest level of PAHs, followed by one of the municipal sludges. The average sum of 5- and 6-ring PAH compounds in all of the sludge samples amounted to almost 65% of the total PAHs. The diagnostic ratios of specific PAHs were calculated to determine the dominant sources for the PAHs in the sludge samples.