engleski

Comparative results of the residual levels of PCBS obtained by GC/ECD and bioassay in soil samples from Kragujevac hot spot after the warfare in former Yugoslavia

During Kosovo intervention in 1999, almost daily attacks on major industrial sources caused numerous industrial accidents (Kragujevac, Pancevo, Novi Sad, Bor etc.)1. The main environmental effects of the bombardments in Kragujevac, ZASTAVA car factory (Paint Shop, Power Plant, Waste Storage) were damaged transformers which contained Pyralene oil. As a consequence of explosions, fires and PCB combustions, very high levels of PCDD/F were also found in soil samples from that area (100, 000 ng I-TEQ/kg). Very high levels of PCBs and PCDD/Fs were also found in samples taken around the transformers of the power plant (70-74 g/kg of PCBs and 10, 200 ng I-TEQ/kg of PCDD/Fs). In 2000, UNEP/UNOPS Clean-up Project YUG 00-R71 was performed for clean-up action of serious environmental damage of hotspots in Former Yugoslavia. The aim of this work was to identify the potentially polluted zone in the vicinity of the destroyed transformers in Kragujevac non-urban area. In December 2002, the sampling of soil was conducted at the localities which were supposed to be still contaminated with PCB2, 3. All the sampling spots are situated on the base of destroyed transformer station. Sampling zone (12x11m) was divided in quadrants and soil samples were taken from the various depths (0.2 – 1.0 m). The results of both analytical methods and bioassay conducted in this study show that in spite of clean-up and decontamination of Kragujevac car factory, residues of PCBs are still found in soil samples from that area. In all soil samples 5 PCB congeners were detected. Congener PCB 28 was identified in samples A-1 and B-1, but it could not be quantitatively determined. According to the results of GC analysis, the center of contamination is the spot A-1, while the most polluted area is determined by spots A-1, B-1 and B-5, regardless the different sampling depths. Presence of PCBs in spot B-5 (1.0 m) indicates their vertical movement into soil, which, according to hydrogeological model could predict even deeper migration of PCBs. In spite of limited data, it can be suggested that the vertical migration of PCBs in soil is more pronounced than horizontal. The results of in vivo bioassay show that all four samples significantly induced EROD activities in immature female rats in a dose-dependent manner. The samples A-1 and B-1 were the most potent, which is in accordance with their high PCB contamination, as determined by GC/ECD. On the other hand, PROD activities were not significantly increased, except with sample A-1 which suggests that concentration of ortho-substituted PCBs in soil is below detection limit of bioassay.

PCBs, war waste, former Yugoslavia

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