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Öğe A Critical Review of Contaminants of Emerging Concern in Reclaimed Wastewater: Implications for Agricultural Irrigation(Springernature, 2025) Yakamercan, Elif; Obijianya, Christian C.; Jayakrishnan, U.; Aygun, Ahmet; Velluru, Sridevi; Karimi, Mahmoud; Simsek, HalisThis critical review examines contaminants of emerging concern (CECs) in reclaimed wastewater used for agricultural irrigation, with a focus on their implications for environmental sustainability, food safety, and human and ecosystem health. Increasing water scarcity and climate change have intensified reliance on reclaimed wastewater, making a clear understanding of CEC behavior essential. Drivers of its use include technological advances, while barriers remain in the form of CEC occurrence, regulatory gaps, and public perception. The fate and transport of CECs in soil, water, and air determine their environmental risks. However, concentrations in treated wastewater from municipal/industrial wastewater treatment plants, desalination plant effluents, and others are typically low, with varying composition among similar wastewater. The incomplete removal causes leakage of CECs into reclaimed wastewater, thereby exhibiting persistence, bioaccumulation, and toxicity that can affect soil quality, plant physiology, and food safety. Plant uptake and long-term impacts depend on contaminant properties, irrigation practices, and crop species. Ecological risk assessments suggest moderate to high risks to aquatic organisms, while human health risks are generally low but may rise under worst-case exposure scenarios. Advanced treatment technologies, controlled irrigation, and soil management strategies can mitigate these risks by reducing bioavailability and enabling better monitoring. This review concludes with recommendations for researchers, practitioners, and policymakers to improve the safe and sustainable use of reclaimed wastewater in agriculture.Öğe Antibiotic ciprofloxacin removal from aqueous solutions by electrochemically activated persulfate process: Optimization, degradation pathways, and toxicology assessment(Science Press, 2024) Yakamercan, Elif; Aygun, Ahmet; Simsek, HalisCiprofloxacin (CIP) is a commonly used antibiotic in the fluoroquinolone group and is widely used in medical and veterinary medicine disciplines to treat bacterial infections. When CIP is discharged into the sewage system, it cannot be removed by a conventional wastewater treatment plant because of its recalcitrant characteristics. In this study, boron-doped diamond anode and persulfate were used to degrade CIP in an aquatic solution by creating an electrochemically activated persulfate (EAP) process. Iron was added to the system as a coactivator and the process was called EAP + Fe. The effects of independent variables, including pH, Fe2 + , persulfate concentration, and electrolysis time on the system were optimized using the response surface methodology. The results showed that the EAP + Fe process removed 94% of CIP under the following optimum conditions: A pH of 3, persulfate/Fe2 + concentration of 0.4 mmol/L, initial CIP concentration 30 mg/L, and electrolysis time of 12.64 min. CIP removal efficiency was increased from 65.10% to 94.35% by adding Fe2 + as a transition metal. CIP degradation products, 7 pathways, and 78 intermediates of CIP were studied, and three of those intermediates ( m/z 298, 498, and 505) were reported. The toxicological analysis based on toxicity estimation software results indicated that some degradation products of CIP were toxic to targeted animals, including fathead minnow, Daphnia magna , Tetrahymena pyriformis , and rats. The optimum operation costs were similar in EAP and EAP + Fe processes, approximately 0.54 euro/m3 . (c) 2024 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.Öğe Comprehensive understanding of electrochemical treatment systems combined with biological processes for wastewater remediation(Elsevier Sci Ltd, 2023) Yakamercan, Elif; Bhatt, Pankaj; Aygun, Ahmet; Adesope, Adedolapo W.; Simsek, HalisThe presence of toxic pollutants in wastewater discharge can affect the environment negatively due to presence of the organic and inorganic contaminants. The application of the electrochemical process in wastewater treatment is promising, specifically in treating these harmful pollutants from the aquatic environment. This review focused on recent applications of the electrochemical process for the remediation of such harmful pol-lutants from aquatic environments. Furthermore, the process conditions that affect the electrochemical process performance are evaluated, and the appropriate treatment processes are suggested according to the presence of organic and inorganic contaminants. Electrocoagulation, electrooxidation, and electro-Fenton applications in wastewater have shown effective performance with high removal rates. The disadvantages of these processes are the formation of toxic intermediate metabolites, high energy consumption, and sludge generation. To overcome such disadvantages combined ecotechnologies can be applied in large-scale wastewater pollutants removal. The combination of electrochemical and biological treatment has gained importance, increased removal performance remarkably, and decreased operational costs. The critical discussion with depth information in this review could be beneficial for wastewater treatment plant operators throughout the world.Öğe Health risk assessment of metal(loid)s for land application of domestic sewage sludge in city of Bursa, Turkiye(Springer, 2023) Yakamercan, Elif; Aygun, AhmetThis study aims to determine the potential health risks (Carcinogenic and non-carcinogenic) of metal(loid)s in sewage sludge samples for agricultural purposes. For this purpose, sewage sludge was collected annually from a domestic wastewater treatment plant, and metal(loid)s were determined by ICP-MS. Metal(loid)s concentration in sludge samples was within the legal standards. No statically significant seasonal variation of metal(loid)s were observed. The total cancer risk and the hazard index (HI) of metal(loid)s through ingestion, dermal, and inhalation exposure from sewage sludge samples were estimated. The main risk contributor to metal(loid)s were Pb, Zn, and Ni. The average HI values were 0.75 (child) and 0.09 (adult). The total carcinogenic risk (TCR) for child and adult was found to be 3.43 x 10(-5) and 2.31 x 10(-5), respectively. EPA risk assessment model and Monte Carlo Simulation were used to estimate probability and sensitivity distributions for carcinogenic and non-carcinogenic risks. Sensitivity analysis showed that metal(loid)s concentration, exposure duration, exposure frequency, and body weight significantly affect total health risk. The sewage sludge can be applied safely in agriculture due to no important carcinogenic and non-carcinogenic risk for child and adult.Öğe Improving microalgae harvesting efficiency: electrochemical techniques and parameter optimization(Royal Soc Chemistry, 2025) Yakamercan, Elif; Guleria, Samriti; Karimi, Mahmoud; Aygun, Ahmet; Bhasin, Aparajita; Simsek, HalisThe harvesting microalgae is a challenging process that requires innovative and efficient technologies to make large-scale cultivation economically viable. This study investigated the effectiveness of electrochemical methods for harvesting microalgae Chlorella vulgaris. The operational parameters, such as electrolysis time, electrical current, and pH, were optimized using the response surface methodology based on the Box-Behnken design. The boron-doped diamond (BDD), aluminum (Al), and iron (Fe) electrodes were tested and compared. BDD-Al showed 99.3% of harvesting efficiency (time: 20 min, current: 100 mA, pH: 9), which is the highest value and a pH of 9. The physicochemical properties of the harvested algae, including lipids, proteins, carbohydrates, total suspended solids, and chlorophyll-a content, were examined. The content of harvested algae was found as 41.07-46.63% for protein, 5.5-16.9% for lipid, and 9.02-12.08% for carbohydrates (sugar). The chlorophyll-a concentrations varied from 6.7 to 8.36 mu g mL-1. Optimized operating conditions for electrolysis time, pH, and current were determined, and harvesting efficiency was achieved at more than 99%. Energy consumptions for the highest harvesting efficiencies were found to be 0.2, 0.35, and 0.4 kWh kg-1 for BDD-Al, Al-Al, and Al-BDD electrode pairs, respectively. These values were lower than those of conventional algae harvesting methods. The results showed that the electrochemical harvesting techniques are promising alternatives with a high harvesting efficiency and low energy consumption.Öğe Kozmetik sanayi atıksularının boron doped diamond, pla tin ve metal oksit elektrotlar i le elektrooksidasyon prosesinde arıtılması(2024) Can, Orhan Taner; İlhan, Hilal; Keyikoglu, Ramazan; Elibol, Pınar Sevim; Aygun, Ahmet; Isleyen, MehmetBu çalışmada, yüksek kirlilik içeriğine sahip kozmetik atıksuyunun elektroooksidasyon prosesi ile arıtılabilirliği 3 farklı anot kullanılarak araştırılmıştır. Bu amaçla BDD (Boron Doped Diamond), Pt ve RuO2-IrO2 metal-oksit elektrotları kullanılmıştır. Her bir elektrodun toplam organik karbon (TOK) giderim verimleri tespit edilmiştir ve elde edilen veriler karşılaştırılmıştır. 120 dk.’lık deney süresi sonunda TOK giderim verimleri 0.5, 1 ve 1.5 amper akımlar için sırasıyla BDD anot için %31.6, %57.8 ve %68; Pt anot için %25, %36.5 ve %48; RuO2-IrO2 metal-oksit anot için %22.6, %29.8 ve %42.6 olarak elde edilmiştir. Tüm elektrotlar için deney süresi boyunca TOK giderim verimlerinin zamanla arttığı belirlenmiştir. Deney setleri arasında BDD elektrotun en iyi giderim verimini sağladığı ve bu verimin zamanla arttığı görülmüştür. 120 dk.’lık deney süresi sonunda 1.5 amper için, BDD, Pt ve RuO2-IrO2 metal-oksit elektrotlarının en iyi TOK giderim verimleri sırasıyla %68, %48 ve %42.6 idi.Öğe Optimizing electrochemical methods for fish wastewater treatment in recirculating aquaculture systems(Elsevier, 2024) Yakamercan, Elif; Turco, Ronald F.; Nas, Bilgehan; Hussain, Aya S.; Aygun, Ahmet; Meador, Leland; Simsek, HalisAquaculture operations generate substantial wastewater containing organic matter, total dissolved solids, emerging contaminants, and uneaten food pellets, leading to significant environmental issues. In this study, electrooxidation (EO) treatment methods using a boron-doped diamond (BDD) electrode was employed to remove soluble chemical oxygen demand (sCOD), ammonia (NH3-N), nitrate (NO3--N), nitrite (NO2--N), total dissolved phosphorus (TDP), and total dissolved nitrogen (TDN) from aquaculture wastewater. Response surface methodology (RSM) was used to design experiments and optimize operating parameters. The experiments were tested as follows; pH of 6-8, current density of 30-50 mA/cm(2), and electrolysis time of 20-60 min. The results showed that >93 % removal of NH3-N, NO3--N, NO2--N, TDN, and 86.85 % of sCOD were achieved. TDP removal rate was lower than compared to other pollutants and was found to be 79.41 %. The model estimation values and experimental values agreed with an average coefficient of determination (R-2) of >0.98, and all models were found significant (p < 0.05). The optimized treatment conditions were a pH of 6.97, a current density of 42.36 mA/cm(2), and an electrolysis time of 60 min. Under these conditions, responses were achieved at 87.86, 96.52, 99.18, 94.71, 94.78, and 77.78 % for sCOD, NO2--N, NH3-N, NO3--N, TDN, and TDP. In addition, the kinetic model results confirmed that the operating parameters provided a significant reduction of parameters in the EO process. The results indicated that the EO process can efficiently treat the aquaculture effluent.Öğe Treatment of cosmetic industry wastewater with boron doped diamond, platinum and metal oxide electrodes in electrooxidation process(Pamukkale Univ, 2024) Can, Orhan Taner; Gundogdu, Hilal; Keyikoglu, Ramazan; Elibol, Pinar Sevim; Aygun, Ahmet; Isleyen, MehmetIn this study, treatability of cosmetic wastewater consist high pollution by electrooxidation process was investigated using three different anodes. For this purpose, BDD (Boron Doped Diamond), Pt and RuO2- IrO2 metal -oxide electrodes were used. The total organic carbon (TOC) removal efficiency of each electrode was determined and results were compared. After 120 min of operating time, the TOC removal efficiencies of BDD anode were obtained as 31.6%, 57.8% and 68%; Pt anode were obtained as 25%, 36.5% and 48%; RuO2-IrO2 metal -oxide anode were obtained as 22.6%, 29.8% and 42.6% respectively for 0.5, 1 and 1.5 ampere currents. It is observed that TOC removal efficiency increases with time for all electrodes throughout the operation time. The results showed that BDD electrode provided the best removal efficiency and this efficiency increased by the time of progress. After 120 min of operating time, the best TOC removal efficiencies of BDD, Pt and RuO2-IrO2 metaloxides electrodes were 68%, 48% and 42.6% respectively for 1.5 ampere.
