Civil Engineering / İnşaat Mühendisliği
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Conference Object Citation - WoS: 2Citation - Scopus: 2Arsenic in Groundwater in Western Anatolia, Turkey: a Review(University of Silesia Press, 2010) Gündüz, Orhan; Baba, Alper; Elpit, HandanOccurrence of arsenic (As) in groundwater has been a major problem worldwide for the last hundred years. Considering its toxic effects on human health, the presence of elevated levels of arsenic in groundwater resources used in drinking water supply has been an active research field throughout the world (Van Halem et al., 2009). In this regard, case studies from Bangla-desh, India, Nepal, El Salvador, Ecuador, Honduras, Mexico, Chile, China, Canada, Argentina, Peru, Taiwan, United States, Bolivia and Turkey have been documented with regards to the detection of natural levels in groundwater, the occurrence and distribution mechanisms, the human health effects and the in-situ and ex-situ treatment techniques (Jean et al., 2010). In many of these locations, arsenic is naturally found in the subsurface strata within volcanic and sedimentary formations as well as in areas of geothermal systems related to tectonic activity. Western Anatolia in Turkey is one such area of complex geology with active tectonics and high geothermal potential. This natural setting serves as a suitable environment for the presence of high levels of arsenic in subsurface waters. Based on these fundamentals, this study presents a general overview of arsenic presence in western Anatolia.Conference Object An Integrated Assessment of Water Quality in an Arsenic Containing Aquifer: Milestones From Hydrogeology To Public Health(American Society of Civil Engineers (ASCE), 2012) Gündüz, Orhan; Şimşek, Celalettin; Elçi, Alper; Baba, Alper; Bakar, Çoşkun; Gürleyük, Hakan; Çakır, A.; Mutlu, MerdiyeA multi-disciplinary research is being conducted in Simav Plain, Turkey where an arsenic containing aquifer is at the center of attention. The study is not only aimed to understand the sources and mechanisms of the presence of high arsenic levels in groundwater but also to determine the associated consequences with regards to human health. The high arsenic levels in most groundwater (N=33, avg. 162 ppb), surface water (N=9, avg. 76.6 ppb) and geothermal water (N=3, avg. 406 ppb) samples are strongly related to high occurrences of arsenic in rocks and soils of the plain, which range between 7.1 and 833.9 ppm with an average of 49 ppm. These values correspond to several orders of magnitude higher than international standards and world averages in water and soil, respectively. With this motivation, this research also focuses on human health in the study area associated with exposure to these high arsenic levels via numerous pathways. Consequently, more than 1000 individuals were personally surveyed by public health specialists to determine an inventory of diseases in the area. Furthermore, a verbal autopsy study was also conducted with relatives of the deceased, which were further verified with hospital records, to understand the underlying death cause. As a result, certain cancer rates were found to exceed national averages and the results statistically demonstrated a potential link with high arsenic levels mainly through oral exposure.Conference Object Tracing the Relative Distribution of Arsenic Species in Groundwater and Its Association With Soil Arsenic Levels in the Simav Graben Area, Turkey(2016) Gündüz, Orhan; Şimşek, Celalettin; Elçi, Alper; Baba, Alper; Gürleyük, HakanA comprehensive hydrogeochemical assessment was conducted in the Simav Plain, Turkey where major health concerns were reported and elevated arsenic (As) levels were previously found. Boreholes drilled in the plain were used to take core samples from the alluvial aquifer from which most groundwater was extracted. The results of core analyses revealed several orders of magnitude higher values than global average. Groundwater samples were later collected from these boreholes and analyzed for arsenic and its species as well as other related hydrochemical parameters. The results of groundwater quality assessment revealed that the groundwater in the plain was enriched with arsenic that exceed 1 mg/L level and was mostly under reducing conditions. The dominant arsenic specie in groundwater was arsenite in more than 70% of all samples.Article The Relation of Geogenic and Antrophogenic Factors With Blood and Hair Lead and Arsenic Levels in Women Living in Çan and Bayramiç Districts of Çanakkale Province(Nobelmedicus, 2019) Baba, Alper; Gündüz, Orhan; Bakar, Çoşkun; Sülün, Serdar; Save, DilşadObjective: Mining areas and associated industrial activities carry considerable risks for human health due to multi-pathway exposure of heavy metals such as arsenic and lead. The objective of this study was to compare arsenic and lead levels in human blood and hair samples in an industrial mining area in northwestern Turkey with that of a non-exposed group demonstrating similar sociocultural characteristics. Material and Method: The population of the study consisted of 674 nonsmoker women over the age of 40 who were selected on a random basis from mine region and control area. Venous blood samples were taken and analyzed for blood lead and arsenic levels in all participants. Hair samples were later collected from 108 women with high levels in blood samples. Results: The results showed that the highest prevalence of occurrences was found in district centers whereas relatively lower values were observed in the villages. Hair arsenic and lead levels were comparably higher in the industrialized area (Çan Region) where low-quality coal combustion used in power generation and residential heating were dominant. Conclusion: Although high correlations were not found, blood and hair arsenic and lead levels in individuals living in industrial and agricultural areas were found to be high at levels influencing the human health. On the other hand, these results should be further supported and verified with advanced and long duration monitoring activities.Conference Object Occurrence of Arsenic and Related Microbial Signature of Hydrothermal Systems in Western Turkey(Taylor & Francis, 2012) Chen, Chienyen; Maity, Jyoti Prakash; Bundschuh, Jochen; Bhattacharya, Prosun; Baba, Alper; Gündüz, OrhanThe naturally occurring aqueous Arsenic (As) and other toxic elements are found around the world. The present study concentrates on arsenic concentrations, speciation and related microbial diversity in a hydrothermal system in Western Turkey. The surface temperatures of hot springs reach up to 90°C and deep well (reservoir) temperatures vary in the range of 40 to 230°C. The elements such as As, B, Br, Ba, Cr, Fe, Mn, V and Zn are found in high concentration in hydrothermal waters. Hydrogeochemically, Seferihisar hot spring exhibited a Na-Cl water type. On the other hand, Karahayit, Pamukkale, Emirfaki, Alaşehir and Sart exhibit a Ca-HCO 3 water type and Çitgöl exhibited a Na-HCO 3-SO 4 water type. The arsenic (As) concentrations in geothermal waters of Western Anatolia have been detected to range from 0.03 mg/L to 1.5 mg/L, including Buharkent (İnalti) (1.50 ± 0.005 mg/L), Kizildere (1.13 ± 0.005 mg/L), Eynal (0.71 ± 0.005 mg/L) and Sarayköy (0.06 ± 0.004 mg/L). Arsenic (III) is the dominant species in geothermal water of Western Anatolia. The 16S rRNA gene sequences of bacterial diversity show that the thermophilic, sulfur/thiosulfate-oxidizing bacterium (Thiobacter subterraneus) is present in Kula geothermal water and mesophilic sulfur- and thiosulfate-oxidizing Sulfurovum lithotrophicum bacterium occurs in Sarayköy geothermal spring. Also, Bacillus fumarioli, (a thermophilic, aerobic endospore forming bacterium growing on (NH 4) 2 SO 4, MgSO 4 and MnSO 4 at 50-55°C), Schlegelella thermodepolymerans and Methylocaldum szegediense are rich in geothermal water.Article Citation - WoS: 18Citation - Scopus: 22The Health Risk Associated With Chronic Diseases in Villages With High Arsenic Levels in Drinking Water Supplies(Springer Verlag, 2017) Gündüz, Orhan; Bakar, Coşkun; Şimşek, Celalettin; Baba, Alper; Elçi, Alper; Gürleyük, Hakan; Mutlu, Merdiye; Çakır, AyşeThis study is intended to compare and assess the distribution and possible causes of current chronic diseases in villages with high arsenic levels in drinking water supplies. It is a cross-sectional epidemiological research that analyzes the frequency and underlying risk factors of chronic diseases in villages with varying levels of arsenic exposure through drinking water. Sample space of study included 1003 individuals, 614 of whom were from villages with high arsenic levels in drinking water and remaining 389 were from two control villages with below-limit arsenic levels in drinking water. While nutritional habits and living environments of two groups were similar, cigarette smoking and alcohol use were higher in villages with low arsenic levels. Mini mental state examination test results in 60+ age group were lower in villages with high arsenic levels. Although no statistically significant differences were detected in chronic disease occurrence between the groups, the number of cases was higher in villages with higher percentage of cigarette smoking and alcohol use. Moreover, cases of lung, colon, and stomach cancers were higher in villages with high arsenic levels in drinking water supplies.Conference Object Citation - Scopus: 4High Arsenic Levels in Groundwater Resources of Gediz Graben, Western Turkey(CRC Press, 2016) Baba, Alper; Gündüz, Orhan; Şimşek, Celalettin; Elçi, Alper; Sözbilir, Hasan; Murathan, AlimGediz Graben situated in western Turkey is an area containing extensional structures with active tectonics and geothermal systems that serves as a suitable environment for the presence of high levels of arsenic (As) in groundwater. The results of a comprehensive monitoring program in the basin revealed that the maximum As concentration detected during the monitoring program was 3086 ppb and the average value was calculated to be 23.63 ppb. In addition, As levels in 28% of the water samples were above the 10 ppb limit value making them unsuitable for drinking water supply. These high As concentrations in the basin was mostly associated with long detention times of water in altered rocks located along detachment faults, strong water–rock interaction processes in the alteration zones and anthropogenic influences made within the geothermal fluid reservoir. © 2016 Taylor & Francis Group, London.Article Citation - WoS: 27Citation - Scopus: 31Statistical Analysis of Causes of Death (2005-2010) in Villages of Simav Plain, Turkey, With High Arsenic Levels in Drinking Water Supplie(Taylor and Francis Ltd., 2015) Gündüz, Orhan; Bakar, Coşkun; Şimşek, Celalettin; Baba, Alper; Elçi, Alper; Gürleyük, Hakan; Mutlu, Merdiye; Çakır, AyşeThe purpose of this research was to compare the causes of death in 5 villages situated in Simav Plain, Turkey, during 2005-2010 where different arsenic levels were detected in drinking water supplies. Since groundwater in Simav Plain had arsenic concentrations that ranged between 7.1 and 833.9 ppb, a two-phase research was formulated. In the first phase, public health surveys were conducted with 1,003 villagers to determine the distribution of diseases. In the second phase, verbal autopsy surveys and official death records were used to investigate the causes of death. In total, 402 death cases were found in the study area where cardiovascular system diseases (44%) and cancers (15.2%) were major causes. Cancers of lung (44.3%), prostate (9.8%), colon (9.8%), and stomach (8.2%) were comparably higher in villages with high arsenic levels in drinking water supplies. Furthermore, the majority of cases of liver, bladder, and stomach cancers were observed in villages with high arsenic levels. © 2015 Taylor and Francis Group, LLC.Article Citation - WoS: 2Citation - Scopus: 2Sample Collection Into Sterile Vacuum Tubes To Preserve Arsenic Speciation in Natural Water Samples(American Society of Civil Engineers (ASCE), 2013) Gündüz, Orhan; Gürleyük, Hakan; Çakır, Ayşe; Elçi, Alper; Baba, Alper; Şimşek, CelalettinThe accurate speciation analysis of arsenic is a serious concern for water quality monitoring programs. Because the preservation of sample integrity until analysis is one of the most important aspects of speciation, this study aims to compare the performance of four different sample preservation methods under diverse conditions of sample quality. Natural samples with different characteristics were collected into the following containers to study their effectiveness: (1) standard high-density polyethylene bottle with no preservative; (2) empty, sterile Vacuette tube with no preservative; (3) sterile tripotassium ethylenediaminetetraacetic acid (K3EDTA) Vacuette tube with K3EDTA additive; and (4) empty, sterile Vacuette tube with added hydrochloric acid (HCl). Known concentrations of arsenite [As(III)] were also added to each container to monitor the oxidation of As(III) to arsenate [As(V)]. The results revealed recovery ratios exceeding 95% in all containers with sterile vacuum conditions. In particular, the K3EDTA Vacuette tube yielded a recovery very close to 100% of the spiked As(III), which is known to rapidly oxidize to As(V). Overall, collecting the sample into a container under sterile vacuum conditions and using a universally accepted preserving agent such as EDTA or HCl significantly improved the preservation of the original species distribution in the water matrix studied, compared to sampling without the use of preservation methods. After validation by future research, these sterile vacuum tubes can possibly be utilized for collecting and storing samples for the routine speciation analysis of other elements such as selenium, chromium, and antimony.Article Citation - WoS: 72Citation - Scopus: 90Naturally Occurring Arsenic in Terrestrial Geothermal Systems of Western Anatolia, Turkey: Potential Role in Contamination of Freshwater Resources(Elsevier Ltd., 2013) Bundschuh, Jochen; Maity, Jyoti Prakash; Nath, B.; Baba, Alper; Gündüz, Orhan; Kulp, Thomas R.; Jean, Jiin-Shuh; Kar, Sandeep; Yang, Huai-Jen; Tseng, Yujung; Bhattacharya, Prosun; Chen, ChienyenArsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230°C), while, temperature of hot spring fluids was up to 90°C. The Piper plot illustrated two dominant water types: Na-HCO3 - type for geothermal waters in deep wells and Ca-HCO3 - type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation.