Investigation of organic micropollutant pollution in Izmit Bay: a comparative study of passive sampling and instantaneous sampling techniques.

In this study, we used a comprehensive array of sampling techniques to examine the pollution caused by organic micropollutants in Izmit Bay for the first time. Our methodology contains spot seawater sampling, semi-permeable membrane devices (SPMDs) passive samplers for time-weighted average (TWA), and sediment sampling for long-term pollution detection in Izmit Bay, together. Additionally, the analysis results obtained with these three sampling methods were compared in this study. Over the course of two seasons in 2020 and 2021, we deployed SPMDs for 21 days in the first season and for 30 days in the second season. This innovative approach allowed us to gather sea water samples and analyze them for the presence of polycyclic aromatic hydrocarbons (Σ15 PAHs), polychlorinated biphenyls (Σ7 PCBs), and organochlorine pesticides (Σ11 OCPs). Using SPMD-based passive sampling, we measured micropollutant concentrations: PAHs ranged from 1963 to 10342 pg/L in 2020 and 1338 to 6373 pg/L in 2021; PCBs from 17.46 to 61.90 pg/L in 2020 and 8.37 to 78.10 pg/L in 2021; and OCPs from 269.2 to 8868 pg/L in 2020 and 141.7 to 1662 pg/L in 2021. Our findings revealed parallels between the concentrations of PAHs, PCBs, and OCPs in both SPMDs and sediment samples, providing insights into the distribution patterns of these pollutants in the marine ecosystem. However, it is worth noting that due to limited data acquisition, the suitability of spot sampling in comparison to instantaneous sampling remains inconclusive, highlighting the need for further investigation and data collection.

Integrated assessment of eutrophication in the southern Black Sea waters, using the Nested Environmental Status Assessment Tool.

This research deals with the land-based pressures on the southern Black Sea coast (Turkey), with the objective of assessing their eutrophication impacts. In this context, reference values of some of the eutrophication indicators were calculated, and eutrophication assessment was carried out for this area using the holistic approach NEAT (Nested Environmental Status Assessment Tool). In addition, correlations between NEAT results of coastal regions and pressure-impact analysis methods were investigated. In the determined Spatial Assessment Unit (SAU) areas, 9 indicators were evaluated according to the SAU surface, both with and without weighting by their size the overall assessment of the Turkish Black Sea coast is good (0.70) and moderate (0.57) environmental status, for non-weighting and weighting by SAUs, respectively, with a high confidence level. With this study, we concluded that the sensitivity of the assessment tool needs to be increased. Despite these results, an appropriate number of indicators to represent the water column should be added. It is important to include the phytoplankton variable in the evaluation in future studies. In addition, this study, which uses NEAT allows identifying problematic environmental areas that require attention and action from managers and policymakers.

Fast scanning of illegal oil discharges for forensic identification: a case study of Turkish coasts.

Increasing marine traffic, over 55,000 ships visit per year, through the Turkish Straits System and the Sea of Marmara, produces a yearly average of 12 illegal oil discharges. This paper documents the comparison of chemical fingerprints of spilled oil with suspected sources of oils for identifying the source of illegal pollution in Turkey's seas. Fingerprinting is initiated by comparison of the synchronous fluorescence spectra (Δ=20 or 15 nm) of fugitive and suspected source oils. Potential matches of the spectra/chromatogram are confirmed or rejected by subsequent comparison of Fourier transform infrared spectrometry (FTIR), high-pressure liquid chromatography (HPLC) and gas chromatography with a flame ionisation detector (GC-FID) analysis results. In this study, 39 clean sea waters, 41 polluted sea waters and 111 suspected samples were analysed. According to the comparison of the suspected source sample and polluted sea water sample spectra by using spectrofluorometric analysis, 76 suspected source samples were categorised as non-match whilst 35 suspected samples were classified as match or probable match. Then, match and probable match samples were analysed by using further selected chromatographic methods. Finally, 28 suspected source samples were confirmed as a match, enabling legal proceedings to be initiated.