Samples of Mugil cephalus and Mullus barbatus were collected in the Northeast Mediterranean coast of Turkey the contents of cadmium, copper, iron, zinc and lead in the liver, gill and muscle tissues were determined by atomic absorption flame spectrophotometry.Except for lead, highest levels of each metal were found in the liver and this was followed by the gill and muscle in both species. Among the metals analyzed, Cu, Zn and Fe were the most abundant in the different tissues while Cd and Pb were the least abundant both in M. cephalus and M. barbatus. Seasonal changes in metal (Cd, Cu, Pb, Fe and Zn) concentration were observed in the tissues of both species, but these seasonal variations may not influence consumption advisories. In general, the highest concentrations were detected for all metals in summer. 相似文献
The present study was undertaken as part of the first application and evaluation of the BREF (Best Available Techniques; BAT Reference Document) Textile Document within the context of the European Union's Integrated Pollution Prevention and Control (IPPC) Directive to a large scale textile mill in Turkey. The BAT requirements for the denim manufacturing textile mill were selected in cooperation with the factory management. Detailed mass balance calculations were conducted to evaluate the overall effect of the selected BAT options. The initial findings indicated that the adoption of the selected BAT options resulted in considerable savings in water and energy consumption in the mill. Besides the installation of flow meters and use of semi-counter current rinsing in the most water-intensive processes, minimization of wash waters in the water softening plant, reuse of the concentrate stream from the reverse osmosis plant and compressor cooling waters provided a 29.5% reduction in the total specific water consumption of the mill, reaching the lower limits suggested by the BREF Textile Document. In terms of energy consumption, use of waste heat from finishing wastewater streams in heating up the wash waters, heat insulation and maintenance applications in addition to BAT measures taken for water minimization reduced specific energy consumption by 9% achieving the limits set by the BREF Textile Document. 相似文献
Background Olive mill wastewater (OMW) generated by the olive oil extracting industry is a major pollutant, because of its high organic
load and phytotoxic and antibacterial phenolic compounds which resist biological degradation. Mediterranean countries are
mostly affected by this serious environmental problem since they are responsible for 95% of the worldwide oliveoil production.
There are many methods used for OMW treatment, such as adsorption, electro coagulation, electro-oxidation, biological degradation,
advanced oxidation processes (AOPs), chemical coagulation, flocculation, filtration, lagoons of evaporation and burning systems,
etc. Currently, there is no such economical and easy solution. The aim of this study was to evaluate the feasibility of decolourization
and removal of phenol, lignin, TOC and TIC in OMW by UV/H2O2 (AOPs). The operating parameters, such as hydrogen peroxide dosage, times, pH, effect of UV and natural sunlight were determined
to find the suitable operating conditions for the best removal. Moreover, there is no study reported in the literature related
to the use of UV/H2O2 and lime together in OMW treatment.
Methods OMW was obtained from an olive-oil producing plant (Muğla area of Turkey) which uses a modern production process. No chemical
additives are used during olive oil production. This study was realised by using two different UV sources, while taking the
time and energy consumption into consideration. These two sources were mercury lamps and natural sunlight. Before starting
AOPs experiments, one litre of OMW was treated by adding lime until a pH of 7.00. Then, 100 ml was taken from each sample,
and 1 to 10 ml of a 30% H2O2 (Riedel-deHaen) solution was added. These solutions in closed vessels were laid in the natural sunlight for a week and their
compositions and colour changes were analysed daily by UV-Vis spectrophotometer. At the end of the one-week period, they were
treated with lime. In this study, the effect of changes in the initial pH, times and H2O2 concentrations on removal was investigated. At the end of all experiments, changes in colour, phenol, lignin, TOC and TIC
concentrations were analysed according to standard methods.
Results and Discussion In the samples exposed to natural sunlight and having an H2O2/OMW ratio of 3 ml/100 ml, a significant colour removal was achieved approximately 90% of the time at the end of 7 days. When
the same samples were treated with lime (pH: up to 7), 99% efficiency was achieved. When phenol and lignin removals were examined
in the same concentration, phenol and lignin removal were found 99.5%, 35%, respectively. However, for maximum lignin removal,
more use of H2O2 (10 ml H2O2/100 ml OMW) was found to be necessary. Under these conditions, it was found that lignin can be removed by 70%, but to 90%
with lime, at the end of a seven-day period. Rate constants obtained in the experiments performed with direct UV were found
to be much higher than those of the samples exposed to natural sunlight (kalignin = 0.3883 ≫ kblignin = 0.0078; kaphenol = 0.5187 ≫ kbphenol = 0.0146). Moreover, it should be remembered in this process that energy consumption may induce extra financial burden for
organisations.
Conclusions It was found, in general, that colour, lignin, total organic carbon and phenol were removed more efficiently from OMW by using
H2O2 UV and lime OMW. Moreover, in the study, lime was found to contribute, both initially and after radical reactions, to the
efficiency to a great extent.
Recommendations and Perspectives Another result obtained from the study is that pre-purification carried out with hydrogen peroxide and lime may constitute
an important step for further purification processes such as adsorption, membrane processes, etc. 相似文献
The rapid industrialization and urbanization of an area require quick preparation of actual land use/land cover (LU/LC) maps in order to detect and avoid overuse and damage of the landscape beyond sustainable development limits. Remote sensing technology fits well for long-term monitoring and assessment of such effects. The aim of this study was to analyze LU/LC changes between 1980 and 1999 in Samsun, Turkey, using satellite images. Three Landsat images from 1980, 1987 and 1999 were used to determine changes. A post classification technique was used based on a hybrid classification approach (unsupervised and supervised). Images were classified into six LU/LC types; urban, agriculture, dense forest, open forest-hazelnut, barren land and water area. It is found that significant changes in land cover occurred over the study period. The results showed an increase in urban, open forest/hazelnut, barren land and water area and a decrease in agriculture and dense forest in between 1980 and 1999. In this period, urban land increased from 0.77% to 2.47% of the total area, primarily due to conversions from agricultural land and forest to a lesser degree. While the area of dense forest decreased from 41.09% to 29.64% of the total area, the area of open forest and hazelnut increased from 6.73% to 11.88%. 相似文献
Waste water pollution in industrial areas is one of the most important environmental problems. Heavy metal pollution, especially chromium species in waste water sources from tannery affects our lives. Kocabas Stream is located in south-west Marmara region and Biga town is positioned in the sub basin on the stream. This water source functions as the water for irrigation in agriculture, drinking water for animals and for human use. Thus, this study is of great importance. Waste water pollution can affect all ecosystems and human health by directly or indirectly as in food chain. The concentration of heavy metals (Pb, Cd, Cu, Zn and Cr) were pre-analysed by ICP-AES method in water samples taken from sub-basin of Kocabas stream. In the results of these analyses, concentrations of the metals except chromium were founded at the limit value. But the total concentration of the Cr was found at high levels of between 0.0082 +/- 0.0001 and 5.7231 +/- 0.0921 mg l(-1) over the limit value (0.05 mg l(-1); WHO, EPA, TSE 266 and inland water quality classification) at sampling points very close to tannery factories. Also physicochemical and microbiological parameters of Kocabas Stream were determined. The effects of the experimental results on environment were investigated. 相似文献
The practice of adding substances to make water safe to drink and its consequential effects on human health have been a contentious matter for a long time. In this study, the addition of fluoride in drinking water was evaluated after examining two different countries: Britain and Turkey. This study has used an independent and ethical approach taking into account the cautious but assertive dentists’ comments on the addition of fluoride for years. This research focuses on a comparative analysis of Britain, an advanced economy, and Turkey, a developing country, supported with tangential reference to worldwide practice in general. Drawing on ongoing studies, the research analyses empirical evidence and arguments to conduct an assessment of Turkey’s practices. The ethical argument about fluoridation focuses on the question of adequate evidence for its health benefits and the autonomy of the consumer. As the consumer is not fully consulted about this practice, it could be argued that the will of the consumer can be put to the test in the democratic process. Hence, the key to any policy has to be about both clarity of the national government intention and continued engagement with consumer groups at regional level. 相似文献
Alginates are natural polymers composed of mannuronic and guluronic acid residues. They are currently extracted from brown algae; however, alginate can also be synthesized by some species of Azotobacter and Pseudomonas. Alginates with different proportion of mannuronic and guluronic acids are known to have different characteristics and form gels at different extents in the presence of calcium ions. The aim of this work was to investigate the usefulness of alginate as a non-toxic coagulant used in purification of drinking water. This study utilized alginates from Azotobacter vinelandii having different guluronic acid levels. These were obtained partly by changing the cultivation parameters, partly by epimerizing a purified alginate sample in vitro using the A. vinelandii mannuronan C-5 epimerase AlgE1. The different alginates were then used for coagulation together with calcium. The results showed that turbidity removal capability was dependent on the content of guluronic acid residues. For the best performing samples, the turbidity decreased from 10 NTU to 1 NTU by the use of only 2 mg/L of alginate and 1.5 mM of calcium chloride.
Excessive doses of toxic metals such as cobalt may cause detrimental hazards to exposed organisms. Six groups of onion bulbs were formed to investigate the therapeutic effects of grape seed extract (GSE) against cobalt(II) nitrate (Co(NO3)2) exposure in Allium cepa L. root tips. Control group was irrigated with tap water, while the latter groups were exposed to 150 mg/L GSE, 300 mg/L GSE, 5.5 ppm Co(NO3)2, 5.5 ppm Co(NO3)2 + 150 mg/L GSE and 5.5 ppm Co(NO3)2 + 300 mg/L GSE, respectively. Co(NO3)2 treatment seriously inhibited the root growth, germination and weight gain of the bulbs. Mitotic index was significantly decreased, whereas the chromosomal aberrations and micronuclei incidence exhibited a remarkable increase. In addition, Co(NO3)2 induced a variety of anatomical disorders in onion roots. Lipid peroxidation levels of the cellular membranes were assessed measuring the malondialdehyde content (MDA). MDA amount in Co(NO3)2-treated group reached the highest level among all groups. Co(NO3)2 treatment enhanced the activity of superoxide dismutase and catalase. The addition of GSE to Co(NO3)2 solution substantially suppressed the negative effects of Co(NO3)2 in a dose-dependent manner by strengthening the antioxidant defence system and reducing the cytotoxicity. Moreover, there was a significant recovery in growth parameters following the grape seed addition to Co(NO3)2. GSE had a remarkable reduction in genotoxicity when treated as a mixture with Co(NO3)2. Overall data obtained from this investigation proved that GSE, as a promising functional by-product, had a protective effect on Allium cepa L. against the toxic effects of Co(NO3)2.