Sürdürülebilir Yeşil Kampüs Koleksiyonu / Sustainable Green Campus Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7755
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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: 9Citation - Scopus: 13An Exposure–risk Assessment for Potentially Toxic Elements in Rice and Bulgur(Springer Verlag, 2017) Sofuoğlu, Sait Cemil; Sofuoğlu, AysunRice and wheat are rich sources of essential elements. However, they may also accumulate potentially toxic elements (PTE). Bulgur, the popular alternative to rice in the eastern Mediterranean, is produced by processing wheat, during which PTE content may change. This study determined PTE concentrations in rice and bulgur collected from 50 participant households in the City of Izmir, Turkey, estimated ingestion exposure, and associated chronic-toxic and carcinogenic human health risks. Comparison of the determined concentrations to the available standard levels and the levels reported in the literature revealed that Cd, Co, and Pb in rice might be of concern. The estimated health risks of individual participants supported this result with exceedance of respective threshold or acceptable risk levels at the 95th percentile. Population risk estimates indicated that the proportion with higher than the threshold or acceptable risk is about 10%, 24%, and 12% for Cd, Co, and Pb in rice, respectively. Results of this study showed that health risks associated with PTE exposure through bulgur consumption are lower than those of rice, and below the threshold or acceptable risk levels.Article Citation - WoS: 23Citation - Scopus: 22Optimization of Chemical and Instrumental Parameters in Hydride Generation Laser-Induced Breakdown Spectrometry for the Determination of Arsenic, Antimony, Lead and Germanium in Aqueous Samples(Elsevier Ltd., 2013) Ünal Yeşiller, Semira; Yalçın, ŞerifeA laser induced breakdown spectrometry hyphenated with on-line continuous flow hydride generation sample introduction system, HG-LIBS, has been used for the determination of arsenic, antimony, lead and germanium in aqueous environments. Optimum chemical and instrumental parameters governing chemical hydride generation, laser plasma formation and detection were investigated for each element under argon and nitrogen atmosphere. Arsenic, antimony and germanium have presented strong enhancement in signal strength under argon atmosphere while lead has shown no sensitivity to ambient gas type. Detection limits of 1.1mgL-1, 1.0mgL-1, 1.3mgL-1 and 0.2mgL-1 were obtained for As, Sb, Pb and Ge, respectively. Up to 77 times enhancement in detection limit of Pb were obtained, compared to the result obtained from the direct analysis of liquids by LIBS. Applicability of the technique to real water samples was tested through spiking experiments and recoveries higher than 80% were obtained. Results demonstrate that, HG-LIBS approach is suitable for quantitative analysis of toxic elements and sufficiently fast for real time continuous monitoring in aqueous environments.