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    Competitive biosorption of different forms of lead [Pb(NO3)2 and Pb(CH3COO)2] on growth, biomass and proline in Spirulina platensis (Cyanophyta)
    (Academic Journals, 2011) Sayin, Selin; Yilmaz, Ayse Bahar; Ergun, Nuray; Turan, Funda
    Spirulina platensis growth parameters [chlorophyll a (chl a) and dry-wet weight] effects on proline content, lead accumulation and the combined effect of the different forms of lead [Pb (NO3)(2), Pb (CH3COO)(2)] and pH (6 to 8) were investigated for 192 h. The accumulation and form of lead were determined to be effective on growth parameters. While the highest chl a value (562.37 mu gl(-1)) and lead accumulation (58.74 mu gg(-1)) were found in medium with 30 mgl(-1) Pb (CH3COO)(2) and pH 6, the highest proline content was found in 30 mgl(-1) Pb (NO3)(2) and pH 6. This study depict an inverse relationship between lead accumulation in the test algae and low pH which suggests that proline might be produced at the expense of the material(s) required for the development of S. platensis.
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    HEAVY METAL POLLUTION IN AQUATIC ENVIRONMENTS
    (Nova Science Publishers, Inc, 2010) Yilmaz, Ayse Bahar
    Metals which in their standard state have a specific gravity (density) of more than about 5 g cm(-3) are described as 'heavy metals'. Some of them, such as copper, iron, chromium, zinc and nickel are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. Only when present in greater quantities, these can cause metabolic anomalies like the heavy metals lead, cadmium, arsenic and mercury which are already toxic in very low concentrations. Heavy metals are produced from a variety of natural and anthropogenic sources. Human beings release a high anthropogenic emission of heavy metals into the biosphere. Waste (i.e. emission, wastewater and waste solid) is the origin of heavy metal pollution to water, soil and plants. In aquatic environments, metal pollution can arise from direct atmospheric deposition, geological weathering or through discharge of agricultural, municipal, residential or industrial waste. Under certain environmental conditions, heavy metals may accumulate to a level of toxic concentration causing ecological damage. As a result, living things inhabited contaminated waters may show rather high metal concentrations. In addition, metal bioaccumulation causes biochemical or pathological effects on fish resulting in decrease of growth, fecundity and survival. The members from the upper level of the food chain may carry a critical level of metals and are hence more explanatory than observing water or sediments. Therefore, numerous reports describe metal residues in aquatic organisms such as mussels, shrimp and wild fish from marine and freshwater species. Such studies have been carried out to determine the levels of some heavy metals in some tissues of aquatic organisms from marine and inland waters. Liver, spleen and kidney tissues are known to have high metabolic activities and thus have been used to observe the level of absorbed metals. Gonads, which can be attributed to the reproductive cycle of fish, have also accumulated high amounts of heavy metals. Metal concentrations in the skin and gills have reflected the concentration of metals in waters. Although it is well known that muscle is not an active tissue in accumulating heavy metals, muscle tissue accumulation levels were also studied because of their consumption by humans. Metal uptake by aquatic organisms from contaminated water may differ depending on its ecological needs and metabolism, as well as other factors such as salinity, temperature, contamination gradients of water, food, sediment and interacting agents. Two main objectives prevail in aquatic pollution monitoring programs: (1) determining contaminant concentrations in consumed part of organisms considering the health risk for humans, and (2) using organisms as an environmental indicator of aquatic ecosystem's quality.
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    Heavy metal pollution in aquatic environments
    (Nova Science Publishers, Inc., 2011) Yilmaz, Ayse Bahar
    Metals which in their standard state have a specific gravity (density) of more than about 5 g cm-3 are described as 'heavy metals'. Some of them, such as copper, iron, chromium, zinc and nickel are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. Only when present in greater quantities, these can cause metabolic anomalies like the heavy metals lead, cadmium, arsenic and mercury which are already toxic in very low concentrations. Heavy metals are produced from a variety of natural and anthropogenic sources. Human beings release a high anthropogenic emission of heavy metals into the biosphere. Waste (i.e. emission, wastewater and waste solid) is the origin of heavy metal pollution to water, soil and plants. In aquatic environments, metal pollution can arise from direct atmospheric deposition, geological weathering or through discharge of agricultural, municipal, residential or industrial waste. Under certain environmental conditions, heavy metals may accumulate to a level of toxic concentration causing ecological damage. As a result, living things inhabited contaminated waters may show rather high metal concentrations. In addition, metal bioaccumulation causes biochemical or pathological effects on fish resulting in decrease of growth, fecundity and survival. The members from the upper level of the food chain may carry a critical level of metals and are hence more explanatory than observing water or sediments. Therefore, numerous reports describe metal residues in aquatic organisms such as mussels, shrimp and wild fish from marine and freshwater species. Such studies have been carried out to determine the levels of some heavy metals in some tissues of aquatic organisms from marine and inland waters. Liver, spleen and kidney tissues are known to have high metabolic activities and thus have been used to observe the level of absorbed metals. Gonads, which can be attributed to the reproductive cycle of fish, have also accumulated high amounts of heavy metals. Metal concentrations in the skin and gills have reflected the concentration of metals in waters. Although it is well known that muscle is not an active tissue in accumulating heavy metals, muscle tissue accumulation levels were also studied because of their consumption by humans. Metal uptake by aquatic organisms from contaminated water may differ depending on its ecological needs and metabolism, as well as other factors such as salinity, temperature, contamination gradients of water, food, sediment and interacting agents. Two main objectives prevail in aquatic pollution monitoring programs: (1) determining contaminant concentrations in consumed part of organisms considering the health risk for humans, and (2) using organisms as an environmental indicator of aquatic ecosystem's quality. © 2010 Nova Science Publishers, Inc. All rights reserved.
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    Heavy metals in water and in tissues of himri (Carasobarbus luteus) from Orontes (Asi) River, Turkey
    (Springer, 2008) Yilmaz, Ayse Bahar; Dogan, Mustafa
    Concentrations of heavy metals (Ag, Cd, Cr, Cu, Fe, Ni, Pb ve Zn) were measured in running water and in tissues (muscle, liver, gill, skin and gonads) of one commercially valuable fish species (Carasobarbus luteus) from the Orontes (Asi) River (Guzelburc region) in Hatay (Southeastern Turkey). Results for levels in water compared with national and international water quality guidelines were found at the highest concentrations in international criteria's WHO, EC and EPA, but Cd, Cu, Ni and Pb were found to exceed permissible level of drinking water in national criteria TSE-266 whereas Fe, Zn and Cr concentrations were within the permissible levels for drinking. The present study showed a significant seasonal variation (p < 0.05) in the concentration of the studied metals in the selected tissues, except gonads (p > 0.05), which showed seasonal variation of only Zn (p < 0.05). Maximum concentrations of Ag, Cd, Cr and Pb were detected in gonads followed by liver, gill, skin and muscle while maximum concentrations of Cu, Fe, Ni and Zn were detected in liver followed by other tissues. Concentrations of heavy metals in the muscle of C. luteus were below the permissible limit for human consumption, level of Cu being very close to the permissible limit. Consequently, continuous monitoring of heavy metal concentration in edible freshwater fish will be needed in Orontes River.
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    Metal concentrations in different tissues of jellyfish (rhopilema nomadica galil, 1990) in Iskenderun Bay, Northeastern Mediterranean
    (2013) Duysak, Onder; Yilmaz, Ayse Bahar; Mazlum, Yavuz
    In this study, the concentrations of heavy metals (Cd, Cr, Cu, Fe, Mn, Pb and Zn) were determined in gastral, tentacular and epidermal (umbrella) tissues of jellyfish Ropilema nomadica from 2 stations (Yumurtalik and Arsuz) in Iskenderun Bay, Turkey. Heavy metal concentrations varied significantly depending on the type of the tissue and location of stations. The average metal concentrations in gastral and tentacular were found higher than umbrella tissues in all samples. The level of Mn and Zn concentrations were significantly different among the tissues in both stations (p<0.05). The aim of this study was to imply potential of heavy metal accumulation in jellyfish which plays an important role in biological transfer and Summer blooms. Moreover, this is the first study of the heavy metal bioaccumulation on R. nomadica in Northeastern Mediterranean. © Medwell Journals, 2013.
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    Metals (major, essential to non-essential) composition of the different tissues of three demersal fish species from Iskenderun Bay, Turkey
    (Elsevier Sci Ltd, 2010) Yilmaz, Ayse Bahar; Sanguen, Mustafa Kemal; Yaglioglu, Deniz; Turan, Cemal
    This study was performed to investigate certain major and toxic metal concentrations in different tissues of three demersal fish species (Triglia lucerna, Lophius budegassa, Solea lascaris). Generally, skin and liver exhibited higher metal concentrations than did muscle. Sodium and arsenic concentrations were found at higher levels in muscle tissues than in livers and skin, while zinc and nickel in different organs were classified as follows: skin > liver > muscle tissues. The concentrations of trace metals in fish samples indicated that S. lascaris was more contaminated than were other fish species, followed by L. budegassa and T. lucerna. It may be concluded that consumption of these species from this region is not likely to pose a threat for human health. However, although the concentrations are below the limit values for fish muscles, a potential danger may emerge in the future, depending on domestic waste waters and industrial activities in the region. Therefore, further monitoring programmes should be conducted. (C) 2010 Elsevier Ltd. All rights reserved.