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281.
以珠海码头作为调查船舶防污漆使用影响的对象,分析了珠海周边海域码头内表层沉积物与海水中的重金属含量,以Cu元素为讨论重点,对其进行污染程度与潜在生态危害的评估。结果表明,码头内表层沉积物中Cu含量明显高于码头外沉积物,离市区较近的香洲码头和金沙滩码头内沉积物受到中等至较高程度的Cu污染,海岛东澳岛码头海水易流通,因此受污染程度较低。使用Hakanson生态危害指数法对沉积物进行评估的结果为低潜在生态危害,但码头内海水中Cu元素含量已高于生态安全限值。  相似文献   
282.
Amisulbrom formulated as suspension concentrate was applied at the rate recommended for Korean melon to determine the dissipation pattern (at two different sites), the pre-harvest residue limit (PHRL), and risk assessments. Samples collected over 10 days were extracted using liquid-liquid extraction (LLE) and cleaned up with solid-phase extraction (SPE) Florisil cartridge. Residual concentrations were determined using liquid chromatography-ultraviolet detector (LC-UVD) and confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The standard showed good instrument response linearity with a correlation coefficient (R 2) = 0.9999, and the recovery ranged from 87.5 to 93.7%. The dissipation half-life calculated from two different sites were found to be 7.0 and 8.8 days for sites 1 and 2, respectively. A PHRL graph constructed from the data indicated that if the residue levels were less than 0.55–0.59 mg/kg 3 days before harvest or less than 0.61–0.74 mg/kg 7 days before harvest, then they would be lower than the maximum residue limits (MRLs) at harvest. Risk assessments showed that the risk quotient (RQ) was 4.39–3.47% at 0 day, declined to 1.53–1.63% at 10 days. Therefore, the current data indicate that the amisulbrom can be applied safely to Korean melon; hence, it is unlikely to induce adverse health effects in consumers.  相似文献   
283.
The cadmium and copper levels were determined in the total of 126 fish samples which belongs to five fish species collected from Sır and Menzelet Dam Lakes in Kahramanmaraş Province by Atomic Absorption Spectrophotometer. The concentrations of heavy metals were expressed as ppm wet weight of tissue. The mean levels of cadmium and copper in muscle, liver and gill tissues of Cyprinus carpiofrom the Menzelet Dam were found as 0.27, 0.91, 1.49 and 0.94, 1.2, 1.05, respectively. The mean levels of Cd in the muscle tissues of Leuciscus cephalusfrom the Menzelet Dam were found 0.32 ppm, Cd wasn't found in tissues of liver and gill. The mean levels of Cu in the muscle, liver and gill tissues were found as 3.17 ppm, 1.19 ppm, 0.96 ppm, respectively. The mean levels of the Cd and Cu in muscle and gill tissues of Acanthobrama marmid from the Sır Dam were found as 1.28, 2.64 and 0.72, 0.08, respectively. The levels of the Cd and Cu in muscle tissues of Cyprinus carpiofrom the Sır Dam were found 0.87 and 0.02 ppm, respectively. The mean levels of the Cd and Cu in the muscle and gill tissues of Chondrostoma regium from the Sır Dam were found to be 0.80, 2.62 and 0.67, 1.34 ppm, respectively. The mean levels of the Cd in the muscle tissues of the Silurus glanis was found as 0.60 ppm. In the muscle of the Silurus glanis from the Sır Dam, Cu was not found. The Sır Dam is more polluted than the Menzelet Dam from the point of Cd but less polluted than the Menzelet Dam From the point of Cu. A relationship was determined between species and their habitating region in terms of the levels reflected metal residues. In this study it was emphasized that the amounts of Cd and Cu in the samples were low, however, seas, lakes, rivers, soil, air and consumed foods etc. has to be controlled routinely.  相似文献   
284.
The aim of this study is to evaluate extensively the characterization and identification of major pollutant parameters by paying attention to the organic chemical pollution for unregulated dumping site leachate in Eskişehir/Turkey. The study that is first and only one research has been very important data related with before new sanitary landfill site in Eskişehir city. For this purpose, in this study leachate samples were collected in-situ at monthly interval for a period of 8 months. Firstly, thirty three physicochemical parameters were monitored. Secondly, SPME technique was used for identification of organic pollutants. Meteorological data were also recorded for the same sampling period to correlate meteorological data and physicochemical parameters. Mean values are used in the correlation analysis. Correlation is shown only for the relationship between air temperature and NO3 . No correlation has been found between rain and leachate quality parameters since the amount of rain was very low during the sampling period. However, analysis results were generally decreased in winter season when each parameter and each sampling point are examined separately. According to correlation between every parameter, especially solid content and dissolved oxygen concentration of leachate is affecting to other parameters. Also, sodium and potassium are changing proportionally with same parameters (suspended solids, fixed solids, dissolved oxygen) and high correlation between chloride and heavy metal concentration is showing. The results were statistically evaluated by use of SPSS 10.0 program. Second part of the study, the leachate was extracted by Solid Phase Microextraction (SPME) technique and then analyzed. Of the methodologies tested in this study, the best one selected was based on 100 μ m polydimethylsiloxane coated fiber (PDMS), headspace with heating (Δ HS) sampling mode and an extraction time of 15 min. at a temperature of 50 o C. Thirty three organic compounds in leachate were identified by GC/MS.  相似文献   
285.
Metal Concentrations in Fish Species from the Northeast Mediterranean Sea   总被引:3,自引:0,他引:3  
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   
286.
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 (ka lignin = 0.3883 ≫ kb lignin = 0.0078; ka phenol = 0.5187 ≫ kb phenol = 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   
287.
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   
288.
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   
289.
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   
290.
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