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Öğe Assessment of 210Po and 210Pb in lichen, moss and soil around Can coal-fired power plant, Turkey(Springer, 2016) Belivermis, Murat; Kilic, Onder; Cayir, Akin; Coskun, Mahmut; Coskun, MunevverThis paper deals with determination of Po-210 and Pb-210 activity concentrations using epigeic moss (Hypnum cupressiforme), bushy soil (fruticose) lichen (Cladonia rangiformis) and surface soil samples in the area around C, an coal-fired power plant, northwest Turkey. Mean activity concentrations of Po-210 and Pb-210 were found to be 303.9 and 425.8 Bq kg(-1) for moss, 161.6 and 259.1 Bq kg(-1) for lichen, and 79.9 and 91.5 Bq kg(1) for soil samples at dry weight, respectively. We propose that distance and altitude of sampling site may be of significant parameters of distribution of both radionuclides.Öğe Comet assay for assessment of DNA damage in greenhouse workers exposed to pesticides(Taylor & Francis Ltd, 2019) Cayir, Akin; Coskun, Mahmut; Coskun, Munevver; Cobanoglu, HayalPurpose: The main goal of the present study was to determine DNA damage in pesticide-exposed greenhouse workers and pesticides non-exposed controls. Materials and methods: The DNA damage was measured by alkaline comet assay method (pH > 13) in 41 greenhouse workers and 45 non-exposed individuals as the control. Pesticide exposure was assessed by duration of working in the greenhouse and pesticide application in the greenhouse time. DNA damage was estimated by arbitrary unit and damage frequency. Results: Arbitrary unit and damage frequency were consistently significantly higher in greenhouse workers than those of the controls (p = 0.001). In terms of gender in greenhouse, DNA damage of female workers was significantly higher than those in male workers (p < 0.05). We found significant correlation between DNA damage and working hours spent. Multiple linear regression analysis showed that working hours in the greenhouse as an indication of pesticide exposure were significantly associated with the DNA damage, which can be attributed to the genotoxic potential of the pesticide mixture. Conclusions: The comet assay is sensitive to detect the damage exposed to chronic effect of pesticides in greenhouse workers. Significant DNA damage was obtained for the exposed group, which was associated with the pesticide exposure.Öğe Comparison of buccal micronucleus cytome assay parameters in the pesticide-exposed greenhouse workers with the controls(Elsevier Ireland Ltd, 2017) Cayir, Akin; Coskun, Munevver; Cobanoglu, Hayal; Coskun, Mahmut[Anstract Not Available]Öğe Comparison of Epigeic Moss (Hypnum cupressiforme) and Lichen (Cladonia rangiformis) as Biomonitor Species of Atmospheric Metal Deposition(Springer, 2009) Coskun, Mahmut; Steinnes, Eiliv; Coskun, Munevver; Cayir, AkinIn the present work epigeic moss (Hypnum cupressiforme Hedw.) and epigeic lichen (Cladonia rangiformis Hoffm.) samples were collected simultaneously in the Thrace region, Turkey according to a regular sampling grid. Whereas the moss was found at all 68 sampling sites, the lichen could be collected only at 25 of the sites, presumably because lichens are more sensitive than mosses with respect to air pollution and climatic variations. All elements showed higher accumulation in the moss than in the lichen whereas element inter-correlations were generally higher in the lichen. All considered the moss was judged to be a better choice than the lichen for biomonitoring of atmospheric deposition of metals in this case, and it is argued that mosses may be generally more suited than lichens for this purpose.Öğe Concentrations of some elements in the Bioindicator Organism Cladonia rangiformis Collected at the Vicinity of Canakkale(Foundation Environmental Protection & Research-Fepr, 2008) Cayir, Akin; Coskun, Muenevver; Coskun, MahmutLichen samples (Cladonia rangiformis) were collected at 10 different sampling sites to determine distribution patterns and concentrations of Al, Ba, Ca, Co, Fe, X, Li, Mg, Mn, Na, Ni, and Ti in lichen at the vicinity of Canakkale. Microwave digestion system was used for mineralization of lichen samples. The concentrations of elements were determined using ICP-OES and the map of spatial distribution of each element's was plotted. Results showed that the distribution patterns of Al, Fe, Ti, Co, and Li were similar in the study area. The highest concentrations of these five elements were determined in Balikesir-Balya region. The distribution of Na, Mg, Ca, and Sr were also similar, and the maximum concentrations of these elements were determined near the sea shore sampling stations.Öğe Cross-border response of mosses to heavy metal atmospheric deposition in Southeastern Bulgaria and European Turkey(Springer, 2009) Coskun, Mahmut; Yurukova, L.; Cayir, A.; Coskun, Muenevver; Gecheva, G.First cross-border atmospheric pollution of 11 heavy metals and toxic elements assessed by Hypnum cupressiforme was reported for a part of Southeastern Europe (Southeastern Bulgaria and European Turkey). Moss monitoring technique followed the main requirements of European Moss Survey. Moss samples were collected in April 2006 both in Bulgaria and Turkey. Concentration of Al, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, and Zn were determined by ICP-AES. Interlaboratory parallel calibration (exchanged four moss samples from each country), standard reference moss materials (M2 and M3) results ensured the study. ANOVA showed no differences between measured results in both laboratories at the 99% confidence level. Principle Component Analyze proved two factors: F1 group of Al, As, Cd, Cr, Fe, Ni, and V and F2 of Cu, Pb, and Zn as main atmospheric pollutants. Results obtained showed approximately Cu and Pb high concentrations around Istanbul and Burgas and Zn pollution in Istanbul district. Arsenic cross-border atmospheric pollution in the study area of Southeastern Europe was found.Öğe Determination of atmospheric heavy metal pollution in Canakkale and Balikesir provinces using lichen (Cladonia rangiformis) as a bioindicator(Springer, 2007) Cayir, Akin; Coskun, Munevver; Coskun, MahmutA regional study was conducted to assess the current level of atmospheric heavy metal pollution (Pb, Zn, Cr, Cu, Cd) in the Canakkale and Balikesir provinces of Turkey, and also to establish a baseline for future studies of atmospheric heavy metal pollution. The lichen Cladonia rangiformis was used for determining the distribution of heavy metals in the atmosphere. The highest concentration of all these elements was observed in the vicinity of Balikesir province where there is an abandoned lead-zinc main. On the other hand, apart from the mining area, the concentration of heavy metals was similar to the data reported for unpolluted areas. Maximum values of Pb, Zn, Cr, Cu, and Cd were 33.8, 47.6, 13.0, 5.29, and 0.69 mg/kg in dry weight, respectively. Spatial distribution of these elements, apart from Cr, was similar. Correlation coefficients between Zn-Pb, Cr-Zn, Cu-Pb, Cu-Zn, Cd-Zn, and Cd-Cr were high and positive, and indicated that they come from the same sources.Öğe Different working conditions shift the genetic damage levels of pesticide-exposed agriculture workers(Springer Heidelberg, 2020) Cobanoglu, Hayal; Coskun, Munevver; Coskun, Mahmut; Cayir, AkinIn the current study, we had two main purposes. Firstly, we aimed to compare genetic damages in the agricultural workers of two different types of environmental conditions including the greenhouse and open fields. Secondly, we aimed to compare genetic damages in the total agricultural workers as the exposed group (greenhouse and open field workers) (n = 114) and the non-exposed control group (n = 98) living in the same area in Canakkale, Turkey. For these purposes, we investigated the incidence of micronucleus (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in peripheral blood lymphocytes. We observed that the frequencies of MN, NPB, and NBUD obtained for the greenhouse workers were statistically significantly higher than those obtained for the open field workers. When the results of the control group were compared with those of the total workers, there were statistically significant differences in terms of MN and NBUD frequencies. We found that age and MN were correlated at a significant level in both the agricultural workers and the control group. The MN frequency of the female workers was 1.5 times greater than that of the male workers, and it was a significant level in the agricultural workers.Öğe DNA damage and circulating cell free DNA in greenhouse workers exposed to pesticides(Wiley, 2018) Cayir, Akin; Coskun, Mahmut; Coskun, Munevver; Cobanoglu, HayalPesticides widely used in agriculture and other applications have been linked to cancer and other diseases through several potential mechanisms. The goals of this study were to assess DNA damage in lymphocytes by the cytokinesis-block micronucleus assay (CBMN), and to measure circulating cell free DNA (ccf-DNA) in the blood of pesticide-exposed greenhouse workers and matched controls living in the same area. CBMN was applied to peripheral blood lymphocyte samples taken at different times (spring and autumn) for each individual. We measured plasma ccf-DNA levels using a Qubit((R)) fluorometer. The results indicated that the MNL, BNMN, and NBUDs frequencies of pesticide-exposed individuals were significantly higher than non-exposed individuals. Apart from MNL, BNMN and CBPI, a season-related effect was found for the NPB and NBUD frequencies. With MNL and BNMN as the dependent variables, multiple regression analysis showed that age and gender affected MN formation. The ccf-DNA level in the pesticide-exposed group was significantly higher than the control group. There was no seasonal variation regarding the free DNA amount. Ccf-DNA in males was found to be higher than females. The MNL, BNMN, NPB, and CBPI did not correlate with the ccf-DNA amount. It can be concluded that pesticide exposure can modulate DNA integrity via different mechanisms. Also, elevated levels of ccf-DNA could be recommended as a biomarker of pesticide exposure. Environ. Mol. Mutagen. 59:161-169, 2018. (c) 2017 Wiley Periodicals, Inc.Öğe Electrochemical oxidation of prednisolone at glassy carbon electrode and its quantitative determination in human serum and tablets by Osteryoung square wave voltammetry(Bentham Science Publ Ltd, 2007) Yilmaz, Selahattin; Skrzypek, Slowomira; Dilgin, Yusuf; Yagmur, Sultan; Coskun, MahmutA simple, rapid, selective and sensitive electrochemical method for the direct determination of prednisolone in spiked human serum and tablets was developed. The electrochemical oxidation and determination of prednisolone has been carried out at glasy carbon electrode (GCE) in various aquaeous solution in the pH range of 0.56-12.30 by cyclic (CV) and Osteryoung square wave voltammetry (OSWV). The best results were obtained for the determination of prednisolone by OSWV method in 0.5 mol L-1 sulphuric acid at about pH 0.56. The peak current and peak potential depends on pH, so its influence and also scan rate were studied. The diffusion controlled by nature of the peak was established. This electroanalytical procedure enabled to determine prednisolone in the concentration range 1.0 X 10(-6)- 2.0 x 10(-5) mol L-1. This limit of detection (LOD) and limit of quantification (LOQ) were obtained as 3.4x10(-7) and 4.5x 10(-7) mol L-1 respectively. Precision and accuracy of the developed method were checked by recovery studies in spiked tablets and human serum.Öğe Evaluation of background DNA damage in a Turkish population measured by means of the cytokinesis-block micronucleus cytome assay(Elsevier, 2013) Coskun, Mahmut; Cayir, Akin; Coskun, Munevver; Tok, HayalThis study aimed to determine the background incidence of micronuclei (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in the peripheral blood lymphocytes of a population in the province of Canakkale, Turkey. Seventy-one individuals living under similar socio-economic conditions, not exposed to an X-ray examination during the last six months, receiving no medical treatment and not involved in agricultural activities were evaluated. In addition to genetic end-points, the cytokinesis-block proliferation index (CBPI) was determined. MN and NBUD frequencies gradually increased with age. MN frequencies of the older group were similar to 7 fold higher than those of the younger group. Multiple linear regression analysis showed that apart from age, no significant effects of various confounding factors on MN and NBUD were observed. NPB frequencies were affected by gender. In the present study, no statistically significant effect was found of smoking on the genetic end-points evaluated, which agrees with results from other studies. (C) 2013 Elsevier B.V. All rights reserved.Öğe Evaluation of circulating cell free DNA as biomarker of pesticide exposure(Elsevier Ireland Ltd, 2017) Cayir, Akin; Coskun, Mahmut[Anstract Not Available]Öğe Evaluation of genotoxic potential of pemetrexed by using in vitro alkaline comet assay(Marmara Univ, Fac Pharmacy, 2017) Cobanoglu, Hayal; Coskun, Munevver; Coskun, Mahmut; Cayir, AkinPemetrexed is a chemotherapeutic drug, approved for the treatment of mesothelioma and non-small cell lung cancer and variety of neoplasm. Chemotherapeutic drugs don't target only cancer cells in treatment. During treatment these drugs encounter with normal cells as well. Therefore, in this in vitro study, it was aimed to investigate the whether genotoxic effect or not of Pemetrexed on normal leukocytes. In vitro alkaline comet assay was used in this study. Leukocytes from human peripheral blood samples from two volunteer donors were used in the study. In the present study, leukocytes were treated with four different concentrations (25, 50, 75, and 100 mu g/ml) of the drug for 1 hour. At concentration of 75 mu g/ml and 100 mu g/ml, there were statistically significant increases in DNA damage compared to the negative control (p<0.05, and p<0.01 respectively). The obtained result shows that Pemetrexed may have genotoxic potential on normal leucocytes.Öğe Evaluation of Metal Concentrations in Mussel M-galloprovincialis in the Dardanelles Strait, Turkey in Regard of Safe Human Consumption(Springer, 2012) Cayir, Akin; Coskun, Mahmut; Coskun, MunevverConcentrations of the elements were evaluated for the first time in Mytilus galloprovincialis in the Dardanelles (Canakkale Strait-Turkey). The concentration of elements were measured in samples collected in 2007, 2008 and 2009, while the concentrations of Fe and Ni were evaluated in samples taken in 2009. The maximum concentrations of Cd, Cr, Cu, Pb, Zn, Fe, and Ni were found to be 1.59, 6.04, 12.01, 6.03, 319.6, 402.79, and 3.52 mg/kg, respectively. In terms of the nutritional aspect, taking into account the values recommended by world health authorities, the concentration of elements can generally be considered not to be at levels posing a health risk.Öğe First Europe-wide correlation analysis identifying factors best explaining the total nitrogen concentration in mosses(Pergamon-Elsevier Science Ltd, 2010) Schroeder, Winfried; Holy, Marcel; Pesch, Roland; Harmens, Harry; Fagerli, Hilde; Alber, Renate; Coskun, MahmutIn this study, the indicative value of mosses as biomonitors of atmospheric nitrogen (N) depositions and air concentrations on the one hand and site-specific and regional factors which explain best the total N concentration in mosses on the other hand were investigated for the first time at a European scale using correlation analyses. The analyses included data from mosses collected from 2781 sites across Europe within the framework of the European moss survey 2005/6, which was coordinated by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). Modelled atmospheric N deposition and air concentration data were calculated using the Unified EMEP Model of the European Monitoring and Evaluation Programme (EMEP) of the Convention on Long-range Transboundary Air Pollution (CLRTAP). The modelled deposition and concentration data encompass various N compounds. In order to assess the correlations between moss tissue total N concentrations and the chosen predictors. Spearman rank correlation analysis and Classification and Regression Trees (CART) were applied. The Spearman rank correlation analysis showed that the total N concentration in mosses and modelled N depositions and air concentrations are significantly correlated (0.53 <= r(s) <= 0.68, p < 0.001). Correlations with other predictors were lower than 0.55. The CART analysis indicated that the variation in the total N concentration in mosses was best explained by the variation in NH4+ concentrations in air, followed by NO2 concentrations in air, sampled moss species and total dry N deposition. The total N concentrations in mosses mirror land use-related atmospheric concentrations and depositions of N across Europe. In addition to already proven associations to measured N deposition on a local scale the study at hand gives a scientific prove on the association of N concentration in mosses and modelled deposition at the European scale. (C) 2010 Elsevier Ltd. All rights reserved.Öğe Frequencies of micronuclei (MNi), nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in farmers exposed to pesticides in Canakkale, Turkey(Pergamon-Elsevier Science Ltd, 2011) Coskun, Mahmut; Coskun, Munevver; Cayir, Akin; Özdemir, ÖztürkThis study aimed to determine the incidence of micronuclei (MNi). nucleoplasmic bridges (NPBs), and nuclear buds (NBUDs) in peripheral blood lymphocytes due to direct exposure to pesticides among 46 farmers in Canakkale, Turkey. 48 non-exposed individuals living in the same socioeconomic conditions were chosen as control. In addition, a cytokinesis-block proliferation index (CBPI) was calculated. MNi and NBUDs frequencies were significantly higher among the farmers (p<0.05). Although the NPB frequency of the farmers was higher than the controls, there was no statistical difference. Multiple linear regression analysis showed that apart from gender, no significant effects of various confounding factors were observed. Regarding CBPI, data obtained for the controls were higher than that of the farmers; however, there was no statistically significant difference. (C) 2010 Elsevier Ltd. All rights reserved.Öğe Genotoxicity of commercial fungicide Cabrio Plus on human cell(Springer, 2016) Cayir, Akin; Coskun, Mahmut; Coskun, MunevverCabrio Plus, a commercial fungicide, is used in agriculture as the control agent for a broad spectrum of diseases including black dot, early blight, late blight and powdery mildew. This study aimed to evaluate the genotoxicity of commercial formulation of Cabrio Plus which has been inadequately evaluated. The genotoxic potential of Cabrio Plus in isolated human peripheral blood lymphocytes was measured by means of an alkaline version of the comet assay (pH > 13) and in whole blood by use of the in vitro micronucleus test. Cabrio Plus induced a statistically significant increase in DNA damage assessed with the in vitro micronucleus assay and the comet assay. Cabrio Plus also induced cytotoxicity in a dose-dependent manner with the in vitro micronucleus assay. It can be concluded that a commercially available pesticide formulation, Cabrio Plus, has the ability to cause DNA damage and cytotoxicity.Öğe Heavy metal and radionuclide levels in soil around Afsin-Elbistan coal-fired thermal power plants, Turkey(Springer, 2012) Cayir, Akin; Belivermis, Murat; Kilic, Onder; Coskun, Mahmut; Coskun, MunevverThis study aimed to determine the incidence of naturally occurring radionuclides Th-232, U-238 and K-40, artificial radionuclide Cs-137, and heavy metals in soil samples collected from the surroundings of Afsin-Elbistan coal-fired thermal power plant in Kahramanmaras Province, Turkey. Physical and chemical properties of the soil samples were also determined. Radiation levels were measured using a gamma multichannel analyzer equipped with an HPGe detector (Canberra 2020). Concentrations of the studied elements were determined using ICP-AES. The average specific activity of Cs-137, K-40, Th-232 and U-238 at standard deviations was found to be 51.4 +/- A 84.9, 409 +/- A 180, 39.8 +/- A 18.8 and 34.4 +/- A 22.0 Bq kg(-1). Radium equivalent activity (Raeq) was calculated to be 122.8 Bq kg(-1), lower than the limits recommended by the OECD. Mean concentrations of heavy metals were 6.29 +/- A 0.77, 70.5 +/- A 20.3, 59.5 +/- A 75.2, 89.8 +/- A 58.9, 26.7 +/- A 23.7, 89.2 +/- A 58.4, 18,806 +/- A 4,273 and 14,634 +/- A 1,166 mg.kg(-1) for Cd, Cr, Cu, Ni, Pb, Zn, Al and Fe, respectively. The Cd content in all samples and maximum values of Cu, Cr and Ni were higher than the limits specified for soil in Turkey.Öğe Heavy metal deposition in moss samples from East and South Marmara Region, Turkey(Springer, 2011) Coskun, Mahmut; Cayir, Akin; Coskun, Munevver; Kilic, OnderA survey of atmospheric heavy metal deposition in the east and south Marmara region, Turkey was carried out in September 2004. For this purpose, moss samples (Hypnum cupressiforme) were collected in a systematic network of 125 sites. Concentrations of the elements (Al, B, Ba, Ca, Cd, Fe, Co, Cr, Cu, K, Li, Mn, Na, Ni, Pb, Sr, Mg, Ti, and Zn) in the moss were used as an indication of the level of air pollution in the region. Significant differences in heavy metal concentrations, especially for Pb, Cd, Cu, and Zn, were recorded in the moss samples collected around industrialized and heavily populated cities (Istanbul, Bursa, BandA +/- rma, Kocaeli, Biga-Can) and in an abandoned lead-mining area (BalA +/- kesir-Balya). A map of the spatial distribution of each element in the region was plotted, and enrichment factors were calculated. VARIMAX principal component analysis was applied to the data obtained, and five different components were obtained. The results showed that Pb, Cu, Cd, and Zn derived from anthropogenic and industrial sources while other elements came mostly from natural sources.Öğe Heavy metal pollution of surface soil in the Thrace region, Turkey(Springer, 2006) Coskun, Mahmut; Steinnes, Eiliv; Frontasyeva, Marina Viladimirovna; Sjobakk, Torill Eidhammer; Demkina, SvetlanaSamples of surface soil were collected at 73 sites in the Thrace region, northwest part of Turkey. Two complementary analytical techniques, epithermal neutron activation analysis (ENAA) and atomic absorption spectrometry (AAS) with flame and graphite furnace atomization were used to determine 35 elements in the soil samples. Concentrations of As, Cd, Co, Cu, Mn, Ni, Pb and Zn were determined using AAS and GF AAS, and ENAA was used for the remaining 27 elements. Results for As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu Eu, Fe, Hf, 1, In, K, La, Mn, Mo, Na, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, Ti, U, V and Zn are reported for the first time for soils from this region. The results show that concentrations of most elements were little affected by the industrial and other anthropogenic activities performed in region. Except for distinctly higher levels of Pb, Cu, Cd and Zn in Istanbul district than the median values for the Thrace region, the observed distributions seem to be mainly associated with lithogenic variations. Spatial distributions of As, Cd, Cr, Cu, Ni, Pb and Zn were plotted in relation to the concentration values in soil using Geographic Information System (GIS) technology.
