Determination of the healthiness of aquaculture fish by enzymes and histopathological methods.

The health of fishes from select aquacultures was investigated by conducting histopathologic and enzymatic analyses, as well as by examining pollutant accumulation rates in fish tissues ranging in age from juvenile to two years old. Histopathologic examinations demonstrated that the fishes had some abnormalities in their livers, spleens, intestines and reproduction systems, such as lipidation, ovotestis formation, lysis and enlargements of the tissues. The occurrence rate of these abnormalities was not very frequent but also not negligible. Statistical analysis demonstrated that enzyme activity (i.e. CAT, EROD, SOD) and protein concentration fluctuated predominantly by age and season. These parameters were not found to be related to the fish farm or other spatial changes, when their existing environmental conditions were not extreme (i.e. polluted or otherwise unsuitable). Metal concentrations (i.e. Ni, Cu, Zn, As, Cd, Pb and Hg) were never found to be higher than national or international regulatory limits. The quality of the fishes caught from optimal farm conditions may be evaluated as good quality for human consumption.

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.

Effects of pyrene on mussels in different experimental conditions.

The toxicity of the polyaromatic hydrocarbon pyrene to Mytilus edulis and Mytilus galloprovincialis was investigated in experiments conducted in the United Kingdom for M. edulis and in Turkey for M. galloprovincialis. Experimental conditions of temperature and salinity were chosen to be appropriate to the ambient conditions in which the mussels typically live. The effect of different feeding regimes on pyrene bioaccumulation and toxicity was also investigated. Feeding rate and neutral red retention biomarker techniques were used for toxicity assessment. An experiment with M. edulis demonstrated that mussels exposed to pyrene accumulated increasing amounts of this compound throughout a 15-day exposure period and that accumulation increased in relation to exposure concentration and with increasing concentration of unicellular algal food material. However, in these experiments, which were protected from UV light, there was no clear relationship between pyrene concentration in tissues and feeding rate. A clear concentration-response relationship was observed between tissue concentration and neutral red retention for days 1 and 7 of the experiment, but this relationship was lost by day 15, with evidence of the cells recovering. A similar experiment was conducted with M. galloprovincialis at a single (high) pyrene concentration in darkness. The feeding rate of the exposed mussels was always lower than the feeding rate of the control mussels, although the difference was insignificant at 7-day exposure. A decreasing trend in health status of the mussels was indicated by the neutral red retention assay results after 7 and 15 days of exposure to pyrene. In a third experiment (with M. galloprovincialis), an illuminated algal chemostat system containing pyrene was inserted in the exposure system as the food source for the mussels. Both biomarker results showed conclusively that toxic effects correlated with pyrene bioaccumulation, though there was no clear evidence for light-enhanced toxicity. These experiments showed that experimental conditions such as salinity, temperature and feeding regime and perhaps the species of mussel used may influence whether pyrene is perceived as being a toxic molecule.

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) distributions in the Bay of Marmara sea: Izmit Bay.

In 1999, the concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), the total PAH and polychlorinated biphenyls (PCBs) were measured in sea water, sediment and mussels collected along the coast of Izmit Bay, the most important bay of the Marmara Sea. The total-PAH concentrations, measured by Spectrofluorometry were in the range of 1.16-13.68 microg/l in sea water, in the range of 30.0 1670.0 microg/g dry weight in sediments and in the range from 5.67 to 14.81 microg/g wet weight in edible part of mussel. HPLC revealed Phenanthrene (three rings), chrysene (four rings) and benz[a]antracene (five rings) to be the dominant PAHs in sea water, while 16 different PAHs compounds were observed and measured in mussel samples. The most pollution occured at Dogu Kanali and Dil Deresi where were the main rivers containing wastes fall into the the Izmit Bay. Although the maximum mono-ortho PCB concentrations in sea water were measured in the Dil Deresi River (26.33 ng/l) and the Solventas (22.19 ng/l) stations, maximum PCB concentrations in mussels were measured in the SEKA (28.11 microg/kg) and the Dil Deresi River (25.68 microg/kg). The dominant congeners of PCBs were from tetra to hexachlorobiphenyls. The toxicity equivalent values were very low in sea water and mussels.