Petroleum hydrocarbon contamination of the Southern Black Sea Shelf, Turkey

Introduction: In this study, total petroleum hydrocarbon (TPH) contents and some aliphatic and aromatic hydrocarbon concentrations were analysed in coastal sediments of hot points collected from along the Southern Black Sea Shelf. Materials and methods: Surface sediment (0-2 cm) samples were collected from the locations using a Van Veen type grab sampler in September 2008 during a cruise on the Pollution Monitoring R/V ARAR. All sampling procedures were carried out according to internationally recognized guide-lines (UNEP 1991). Samples were analysed using a UV-fluorescence spec-trophotometry (UNEP/IOC/IAEA 1992) and gas chromatog- raphy (GC) via a Hewlett-Packard HP6890N series with a selective detector (GC-MSD) after hexane/ dichloromethane extraction. Results and discussion: The ratio C ₁₇ /C ₁₈ varied between 2. 2 and 2. 9 for the surface sediments of TRK 34Y (Samsun), TRK46 (Giresun), and TRK55 (Rize), respectively. These results showed higher marine organic matter accumulation. However, pyrolytic PAHs were found predominant in these areas. In contrast, petrogenic contributions were found at Stations TRK1 (İǧneada), TRK13 (Zonguldak), TRK53 (Trabzon) and TRK61 (Hopa). TPH contents of surface sediments varied between 0. 29 and 363 μg g ^-1 (dry wt) throughout the shelf. The lowest values were measured at Stations TRK1 (İǧneada) and TRK 19 (Barti{dotless}n), whereas the highest values were found at Stations TRK13 (Zonguldak) and TRK 53 (Trabzon).