In this study, the occurrence and distribution of polychlorinated biphenyls (PCBs) were investigated via sampling studies conducted around a thermal power plant (Seyit&ouml / mer, K&uuml / tahya), a scrap metal yard (Kizilirmak, Kirikkale), transformer repair and maintenance facility (Lake Eymir, Ankara), and two organized industrial districts (izmit and Mersin), and 120 samples composed mainly of sediments were collected from those sites. Total PCBs ranged from not detected to 385 ng/g for all samples. Analysis of samples indicates enrichment of PCBs with special emphasis to sediments collected around the Seyit&ouml / mer thermal power plant. Congener specific results indicate domination of profiles by penta- and hexa-chlorobiphenyls. Overall, the PCB concentrations observed in sampling sites are comparable to the background levels of soil/sediments around the world. To identify relevant pollution sources, congener specific data were further evaluated in the subsequent process of source apportionment using Chemical Mass Balance (CMB) receptor model. A general overview of the source apportionment results indicate that equipments (transformers and capacitors) mainly used in the energy generation/transmission and high energy consuming industries as the major PCB sources. PCBs used in open applications were also predicted as sources depending on site characteristics. Overall, indications of contaminated sites are evident in a number of locations / yet, no major contamination is evident in any media according to the current relevant national regulatory actions. However, findings of this study suggest that, over expanded time exposure, threat to the environment and human health may be of concern.

This study extends the work we have previously done by reporting on both gas-phase and particulate phase PCB concentrations in Chicago air as well as giving a first report on airborne OH-PCBs in Chicago. Gas phase PCB concentrations ranged from 43.1 pg/m³ to 2250 pg/m³, with an average concentration of 594 pg/m³ ± 445 pg/m³, and exhibited strong temporal trends. Particulate phase PCBs accounted on average for 4.3% of total PCBs in a sample. OH-PCBs were detected in both the gas and particulate phase and exhibit characteristics of either emission sources or atmospheric reactions depending on the congener.