PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
Browse
5 results
Search Results
Article Hydrogeochemical Assessment and Health Risks of Groundwater in Sahand Volcanic Foreland (NW Iran): Arsenic Speciation and Heavy Metal Risk Indicators(Academic Press Inc Elsevier Science, 2026) Ghayurdoost, Farhad; Zarghami, Mahdi; Sadeghfam, Sina; Jabraili-Andaryan, Nasser; Nikmaram, Sara; Baba, Alper; Mosaferi, MohammadDue to the toxic nature of arsenic (As) and its elevated concentrations in many water resources, numerous studies have focused on understanding its origin, distribution, and impacts. This study aimed to identify the dominant As species in groundwater of the Sahand Volcanic Foothills, assess water quality indices, and examine heavy metal (HM) concentrations to address rising concerns about groundwater contamination. A total of 21 groundwater samples were collected and analyzed in accordance with world health organization (WHO) guidelines. Although most samples fell within acceptable ranges, several (notably S10, S20, and S21) exhibited elevated levels of total dissolved solids (TDS), electrical conductivity (EC), and HMs, particularly iron (Fe) and As. Hydrochemical assessments using Piper, Gibbs, Stiff, and Schoeller diagrams indicated that geochemical processes resulting from rock dissolution were the main factors controlling groundwater chemistry, with limited influence from anthropogenic pollution. According to the groundwater quality index (GWQI), most samples were categorized as "good" to "excellent," though some areas ranged from "moderate" to "very poor." HM pollution indices revealed that As concentrations exceeded permissible limits. Health risk assessments further showed that both oral and dermal exposure posed significant carcinogenic and non-carcinogenic risks, especially for children. Speciation analysis indicated that arsenate (As V) was the dominant form of As, consistent with oxidizing aquifer conditions, and is less biologically hazardous than arsenite (As III). The study highlights the necessity of continuous groundwater monitoring, effective pollution source management, and implementation of protective regulations to mitigate environmental and health risks in the region.Article Nature-Based Solutions in Island Water Management: A Case Study From Bozcaada (Türkiye)(Academic Press Ltd- Elsevier Science Ltd, 2025) Samiloglu, Bilgesu; Baba, Alper; Cuevas, Raquel Marijuan; Gunduz, OrhanNature-based Solutions (NbS) are increasingly recognized for their role in the sustainable management of water resources, especially in Mediterranean regions facing seasonal water scarcity. While their benefits for biodiversity and climate resilience are well documented, there is little research on their application in small island regions where ecological fragility and water scarcity intersect. This study fills this gap by investigating the potential of NbS, particularly rainwater harvesting systems, on the island of Bozcaada (T & uuml;rkiye). A high-resolution Digital Elevation Model (DEM) was developed to delineate the watersheds of the island and analyze the water flow patterns. These watersheds were analyzed for their water retention potential and suitability for rainwater storage. The geological structure, soil type and native biodiversity were included in the site selection process to ensure ecological compatibility. Based on this analysis, optimal locations for ponds were identified and designed to support groundwater recharge and preserve local ecosystems. The results show that strategically placed rainwater ponds can improve seasonal water availability, reduce dependence on external sources and support native species throughout the year. This NbS-based approach provides a replicable framework for sustainable water management on small Mediterranean islands, emphasizing ecological integration and long-term resilience.Article Citation - WoS: 32Citation - Scopus: 35Distribution of Geothermal Arsenic in Relation To Geothermal Play Types: a Global Review and Case Study From the Anatolian Plate (turkey)(Elsevier, 2021) Baba, Alper; Uzelli, Taygun; Sözbilir, HasanArsenic has a natural cycle as it travels underground. It can mix with geothermal fluid in different ways under the control of magmatic and tectonic processes. Geogenic arsenic is present in many geothermal fields in the world at concentrations above the limits set for human health. The arsenic content of geothermal fluids is also related to the concept of geothermal play type, which forms geothermal systems, because the natural processes that form the geothermal system also control the arsenic cycle. In this study, an attempt is made to explain the relationship between the geothermal play type concept and geothermal arsenic circulation. For this purpose, geothermal field examples are given from around the world and Turkey. The result shows that arsenic concentrations can reach significant levels along with plate tectonic boundaries in the world. When arsenic concentrations were evaluated, the effect of major faults on the Anatolian Plate was clearly seen. Also, in the Anatolian plate where volcanosedimentary units are common, geothermal fluids caused more effective alteration along with structural control and increased arsenic concentrations in geothermal systems. This interaction between structural elements, geothermal fluid, and the arsenic cycle shows that the concept of play type in geothermal systems should also be taken into consideration. It was determined that the places with high arsenic values are located within the convective-non-magmatic extensional geothermal play types such as Western Anatolian Extensional System and the North Anatolian Fault. The concept of play type in geothermal systems includes all systematic and external factors that make up these processes. For this reason, it is very important to evaluate the play type classification together with the arsenic cycle.Article Citation - WoS: 58Citation - Scopus: 59Assessment of Different Nanofiltration and Reverse Osmosis Membranes for Simultaneous Removal of Arsenic and Boron From Spent Geothermal Water(Elsevier, 2021) Jarma, Yakubu A.; Karaoğlu, Aslı; Tekin, Özge; Baba, Alper; Ökten, H.Eser; Tomaszewska, Barbara; Kabay, NalanOne of the factors that determine agricultural crops’ yield is the quality of water used during irrigation. In this study, we assessed the usability of spent geothermal water for agricultural irrigation after membrane treatment. Preliminary membrane tests were conducted on a laboratory-scale set up followed by mini-pilot scale tests in a geothermal heating center. In part I, three commercially available membranes (XLE BWRO, NF90, and Osmonics CK- NF) were tested using a cross-flow flat-sheet membrane testing unit (Sepa CF II, GE-Osmonics) under constant applied pressure of 20 bar. In part II, different spiral wound membranes (TR-NE90-NF, TR-BE-BW, and BW30) other than the ones used in laboratory tests were employed for the mini-pilot scale studies in a continuous mode. Water recovery and applied pressure were maintained constant at 60% and 12 bar, respectively. Performances of the membranes were assessed in terms of the permeate flux, boron and arsenic removals. In laboratory tests, the permeate fluxes were measured as 94.3, 87.9, and 64.3 L m?2 h?1 for XLE BWRO, CK-NF and NF90 membranes, respectively. The arsenic removals were found as 99.0%, 87.5% and 83.6% while the boron removals were 56.8%, 54.2%, and 26.1% for XLE BWRO, NF90 and CK-NF membranes, respectively. In field tests, permeate fluxes were 49.9, 26.8 and 24.0 L m?2 h?1 for TR-NE90-NF, BW30-RO and TR-BE-BW membranes, respectively. Boron removals were calculated as 49.9%, 44.1% and 40.7% for TR-BE-BW, TR-NE90-NF and BW30-RO membranes, respectively. Removal efficiencies of arsenic in mini-pilot scale membrane tests were all over 90%. Quality of the permeate water produced was suitable for irrigation in terms of the electrical conductivity (EC) and the total dissolved solids (TDS) for all tested membranes with respect to guidelines set by the Turkish Ministry of Environment and Urbanisation (TMEU). However, XLE BWRO, CK-NF and NF90 membranes failed to meet the required limits for irrigation in terms of boron and arsenic concentrations in the product water. The permeate streams of TR-BE-BW, TR-NE90-NF and BW30-RO membranes complied with the irrigation water standards in terms of EC, TDS and arsenic concentration while boron concentration remained above the allowable limit. © 2020 Elsevier B.V.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.