Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 1Citation - Scopus: 1Airborne and Dust-Bound PBDEs Indoors and Outdoors in Izmir, Türkiye: A Multi-Route Exposure - Risk Assessment(Elsevier Sci Ltd, 2025) Genisoglu, Mesut; Edebali, Ozge; Sofuoglu, Aysun; Turgut, Cafer; Sofuoglu, Sait C.Phased-out flame retardants, e.g., polybrominated diphenyl ethers (PBDEs), persist in environmental media due to their resistance to degradation and ongoing emissions from PBDE containing materials and industrial activities. This study addresses a notable data gap in a unique setting, i.e., & Idot;zmir, T & uuml;rkiye, by investigating PBDE levels at homes, schools, and caf & eacute;/bar/restaurants, and assessing exposure and associated health risks. Indoor and outdoor air and dust samples were collected from rural, suburban, and urban areas. Exposure through ingestion, dermal absorption, and inhalation routes, and associated chronic-toxic and carcinogenic risks were estimated with Monte Carlo Simulation. Despite having been phase-out, house-dust Sigma BDE concentrations remained prevalent with average levels of >2000 ng/g in schools and homes, while outdoors they were <500 ng/g. BDE-209 was the predominant congener with an indoor air concentration of 486 pg/m(3) in schools and 56.7 pg/m(3) in homes. BDE-209 contributed 83.5-90.4 % of the indoor air Sigma BDE concentration in schools, while in homes this contribution ranged from 70.8 to 75.8 %. Aggregate exposure estimates show the predominant PBDE congener, BDE-209, was primarily exposed by accidental ingestion (58.6 %) followed by dermal absorption (21.9 %) and inhalation (19.5 %). Chronic-toxic risk (CTR, for BDE-47, BDE-99, BDE-153, and BDE-209) and carcinogenic risk (CR, for BDE-209) for the ingestion and dermal absorption routes indicated that house-dust and indoor-air PBDE exposures are not found to be considerable for human health. However, the contribution of inhalation route to the aggregate exposure of BDE-28, BDE-47, BDE-100, BDE-99 (87.0 %, 60.5 %, 54.3 %, and 57.3 %, respectively) may indicate the evermore PBDE exposure by inhalation for lower brominated congeners as they become more significant through environmental debromination of the predominant BDE-209.Article Enhanced Catalytic Performance of Rhizomucor Miehei Lipase on Di-N and Diethylhexyl Phthalates: Insights Into Substrate Specificity and Immobilization Strategy(Taylor & Francis Ltd, 2025) Balci, Esin; Rosales, Emilio; Curras, Marta Pazos; Sofuoglu, Aysun; Sanroman, M. A.Di-n-butyl (DnBP) and Diethylhexyl Phthalates (DEHP), known as potential endocrine disruptors, are priority pollutants categorized by many regulatory agencies. Enzymatic degradation is a green and efficient approach to remove PEs in the environment. In this study, the DnBP and DEHP degradation performance of Rhizomucor miehei lipase (palatase) in free and immobilized forms on Halloysite nanoclays (HNCs) in an aqueous system was investigated. Upon enzyme immobilization, the alterations in the palatase's secondary structure were examined using the circular dichroism (CD) analysis. The binding affinity of DnBP and DEHP to palatase was evaluated with molecular docking approaches. The enzyme's immobilization efficiency and relative activity were found to be 80.3% and 87.8%, respectively. CD results revealed that palatase retained its secondary structure to a significant extent. HNCs-palatase (HNCs-P) exhibited a high stability, as the structural integrity of palatase was mostly preserved. Both free palatase (FP) and HNCs-P fully degraded DnBP and DEHP (100 mg/L) to phthalic acid and a degradation pathway of DnBP and DEHP was suggested. Immobilization prevented the enzyme inhibition caused by the accumulation of metabolites. After seven consecutive uses, HNCs-P was still able to degrade DnBP (63.3%) and DEHP (72.8%). Molecular docking results showed that DEHP had a higher affinity for palatase than DnBP. This study suggests that enzyme immobilization onto HNCs can increase their stability and catalytic performance. FP and HNCs-P effectively hydrolyse ester bonds responsible for phthalate toxicity. Considering their high efficiency, FP and HNCs-P can be used as potential phthalate degraders in various environmental remediation processes.Article Citation - WoS: 6Citation - Scopus: 9The Effect of Military Conflict Zone in the Middle East on Atmospheric Persistent Organic Pollutant Contamination in Its North(Elsevier, 2023) Ayrı, İlknur; Genişoğlu, Mesut; Sofuoğlu, Aysun; Kurt Karakuş, Perihan B.; Birgül, Askın; Sofuoğlu, Sait CemilThis study aimed to investigate long-range atmospheric transport of selected POPs released due to the effects of mili-tary conflicts in regions to the south of Turkey's borders. Ten locations were selected to deploy passive air samplers at varying distances to the border on a southeast-west transect of the country, proximity-grouped as close, middle, and far. Sampling campaign included winter and transition months when desert dust transport events occur. Hypothesis of the study was that a decreasing trend would be observed with increasing distance to the border. Group comparisons based on statistical testing showed that PBDE-183, E45PCB, and dieldrin in winter; PBDE-28, PBDE-99, PBDE-154, p,p '-DDE, E14PBDE, and E25OCP in the transition period; and PBDE-28, PBDE-85, PBDE-99, PBDE-154, PBDE-190, PCB-52, E45PCB, p,p '-DDE, and E25OCP over the whole campaign had a decreasing trend on the transect. An analysis of concen-tration ratio to the background showed that long-range atmospheric transport impacted the study sites, especially those of close group in comparison to the local sources. Back-trajectory analyses indicated that there was transport from the conflict areas to sites in the close-proximity group, while farther sampling locations mostly received air masses from Europe, Russia, and former Soviet Union countries, followed by North Africa, rather than the military con-flict areas. In consequence, decrease in concentrations with distance and its relation to molecular weight through pro-portions, diagnostic ratios, analysis of concentration ratio to the background, and back-trajectory analyses support the effect of transport from the military-conflict area to its north.Article Citation - WoS: 15Citation - Scopus: 19Immobilization of Esterase From Bacillus Subtilis on Halloysite Nanotubes and Applications on Dibutyl Phthalate Degradation(Elsevier, 2023) Rosales, Emilio; Pazos, Marta; Sanroman, Maria Angeles; Balcı, Esin; Sofuoğlu, AysunDibutyl phthalate (DBP) is one of the listed phthalic acid esters (PAEs) known as the priority toxicants which exhibit carcinogenic and teratogenic properties and is responsible for endocrine disruption. Therefore, its removal has become a matter to tackle with. In this work, the feasibility of DBP degradation by esterase and lipase enzymes obtained from various microorganisms and the immobilization of the most effective in a clayey material were investigated. Esterase from Bacillus subtilis exhibited the highest degradation efficiency reaching a complete degradation. Its immobilization onto halloysite nanotubes (HNTs) by adsorption method was studied by response surface methodology using a central composite design face-centered. The four selected factors that affect the HNT-enzyme composite generation were: pH, adsorption time, enzyme/HNT (E/H) ratio, and adsorption temperature, and the optimal conditions were determined (pH 7, time 360 min, E/H ratio 0.2, temperature 30oC). Consequently, the activity did not significantly decrease by immobilization, and the adsorption efficiency and relative activity were determined to be 73.15% and 82.7%, respectively. Besides, the immobilization enhanced thermal and storage stability. As for enzyme reusability, after 7 continuous cycles, the composite maintained almost 75% of its initial activity. Both the free enzyme (1 mg/mL) and the composite degraded 100 mg/L DBP with 100% efficiency and several byproducts were detected. Moreover, the composite could be reused for 7 cycles keeping a remarkable catalytic activity. Overall, this study indicated that the HNT-enzyme composite may be used as an effective candidate for remediation of the environmental media contaminated with DBP and other PAEs.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Article Citation - WoS: 4Citation - Scopus: 5Continuous Treatment of Diethyl Hexyl and Dibutyl Phthalates by Fixed-Bed Reactor: Comparison of Two Esterase Bionanocomposites(Elsevier, 2022) Sanroman, Maria Angeles; Balcı, Esin; Rosales, Emilio; Pazos, Marta; Sofuoğlu, AysunThe removal of Diethyl hexyl phthalate (DEHP) and Dibutyl phthalate (DBP) is of great importance due to their potential adverse effects on the environment and human health. In this study, two bionanocomposites prepared by immobilization of Bacillus subtilis esterase by crosslinking to halloysite and supported in chitosan and alginate beads were studied and proposed as a green approach. The esterase immobilization was confirmed by physical-chemical characterization. Bionanocomposite using chitosan showed the best degradation levels in batch tests attaining complete degradation of DBP and around 90% of DEHP. To determine the operational stability and efficiency of the system, two fixed bed reactors filled with both bionanocomposites were carried out operating in continuous mode. Chitosan based bionanocomposite showed the best performance being able to completely remove DBP and more than 85% of DEHP at the different flowrates. These results proved the potential of these synthesized bionanocomposites to effectively remove Phthalic Acid Esters.Article Citation - Scopus: 22Multi‑purpose Reverse Logistics Network Design for Medical Waste Management in a Megacity: Istanbul, Turkey(Springer, 2022) Balcı, Esin; Balcı, Sezin; Sofuoğlu, AysunIn the study, a multi-purpose reverse logistics network has been designed to create effectual management of medical waste (MW) generated in 39 districts of Istanbul, a heavily populated city, during the COVID-19 pandemic as well as that to be generated in the next decade. With the model, the medical waste management system in Istanbul is analyzed during the pandemic and for the next 10 years. The model attempts to integrate economic, environmental, and social objectives within the sustainable development goals. It aims to maximize the number of personnel and government earnings for the estimated MW of a megacity while minimizing the total fixed cost and the cost of carbon emissions and transportation. The results indicated that the existing facilities are sufficient for the treatment and disposal of MW generated even under pandemic conditions. However, the capacity of the sterilization facility could be insufficient to treat the estimated amount of MW in the next decade. Opening a sterilization facility near the sanitary landfill in Komurcuoda with a total management cost of 62,450,332 €/year would be an optimum solution for Istanbul MW. In comparison to the single-purpose model results, the multi-purpose model resulted in approximately 42,000 € more in total cost. Sensitivity analyses show that the amount of MW has the most significant effect on the total cost. This simple model created an effective MW management proposal for Istanbul, which can be a model for megacities.Book Part The Role of Polyurethane Foam Indoors in the Fate of Flame Retardants and Other Semivolatile Organic Compounds(American Chemical Society, 2021) Genişoğlu, Mesut; Sofuoğlu, Sait Cemil; Sofuoğlu, AysunFlame retardant chemicals are added to polyurethane foams (PUFs) during production. These chemicals are released to the environment during the use of PUF containing furniture or building materials. In contrast, organic pollutants such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons, synthetic musk compounds, and volatile organic compounds could be sorbed by PUF depending on the concentration gradient, ambient temperature, and the physicochemical properties. Most of these substances tend to accumulate by adhering to organic matter in dust, particles, and surfaces, as they do not degrade for long periods of time. Sorption-emission cycles of PUF-associated organic compounds prolong their presence in indoor environments, which could increase human exposure. Since these organic compounds might have carcinogenic or chronic-toxic health effects on living organisms, it is important to understand the role of PUF in exposure to these substances in indoor environments. This chapter reviews the literature on the relationship of organic substances with PUF in indoor environments.Article Citation - WoS: 21Citation - Scopus: 24Phytoremediation of Olive Mill Wastewater With Vetiveria Zizanioides (l.) Nash and Cyperus Alternifolius L.(Elsevier, 2021) Gören, Ayşegül Yağmur; Yücel, Arzu; Sofuoğlu, Sait Cemil; Sofuoğlu, AysunOlive Mill Wastewater (OMW) contains high concentrations of contaminants, including organic, nitrogen, and phenolic compounds that are extremely harmful to the environment and human health. The key purpose of this study was to remove total organic carbon (TOC), total nitrogen (TN), and phenolic compounds (TP) from OMW using floating wetland planted with Vetiveria zizanioides (L.) Nash (vetiver) and Cyperus alternifolius L. (umbrella palm) species. A total of eighteen floating wetlands were constructed. Twelve tanks were planted with vetiver and umbrella palm while another six tanks were maintained as unplanted controls. Experiments were conducted with wastewater volume of 56 L for 67 days using 5% (OMW-5) and 15% (OMW-15) treatments of OMW in a greenhouse. The highest TOC, TN, and TP removal efficiencies were found to be 95.3 ± 0.01, 82.7 ± 2.55, and 98.8 ± 0.07% in umbrella palm planted OMW-5, while the removal efficiencies were 84.9 ± 0.38, 92.7 ± 0.37, and 38.9 ± 1.97% in vetiver planted OMW-5. Similarly, the TOC, TN, and TP removal efficiencies in OMW-15 were 89.3 ± 0.28, 40.86 ± 1.73, and 96.8 ± 0.18% with umbrella palm and 89.1 ± 0.70, 23.7 ± 1.27, and 92.1 ± 0.41% with vetiver. The plants accumulated trace elements, especially in the roots, with the order of Fe > Mn > Cu > Zn > B > Pb > Cr > Ni > Co > Cd for umbrella palm. The umbrella palm shoot phenol content was found to be 2358 ± 201 and 1421 ± 198 mg/kg in OMW-5 and OMW-15, respectively. Overall, this study revealed that floating wetlands planted with vetiver and umbrella palm species have the potential to be used as a green treatment method to treat diluted high strength OMW.Article Citation - WoS: 20Citation - Scopus: 21Long Term Stability of Biodegradable Polymers on Building Limestone(Elsevier Ltd., 2019) Kaplan, Zişan; Böke, Hasan; Sofuoğlu, Aysun; İpekoğlu, BaşakSynthetic polymers can be replaced by biodegradable ones as adhesives, water repellents and consolidants on the stone surfaces and facades of the historic buildings in their conservation to minimize future deterioration. In this study, the long-term stability of two biodegradable polymers, polyhydroxybutyrate (PHB) and poly-L-lactide (PLA), and an acrylic polymer (Paraloid B72) which is commonly used in conservation works of artefacts, were evaluated on limestone using a UV lamp-weathering chamber (up to 104 days) for future protection studies. Chemical and morphological changes induced by an accelerated weathering test were examined by Fourier Transform Infrared spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) analyses. Protection efficiency of the polymers was determined by the changes in color, capillary water absorption, static contact angle on limestone. Paraloid B72, PHB, and PLA coatings significantly increased hydrophobicity while decreasing capillarity water absorption and caused negligible change in the color of the limestone. Protection efficiencies of PLA and PHB polymers were almost the same as that of Paraloid B72, a widely used acrylic polymer. However, PLA and PHB seemed to be favorable polymers as protective agents due to their reversibility and biodegradability, low chromatic changes, good hydrophobic behavior and good stability to weathering in reducing the effects of outdoor exposure on limestone surfaces.Article Citation - WoS: 64Citation - Scopus: 78Utilization of Municipal Plastic and Wood Waste in Industrial Manufacturing of Wood Plastic Composites(Springer Verlag, 2020) Başalp, Dildare; Tıhmınlıoğlu, Funda; Sofuoğlu, Sait Cemil; İnal, Fikret; Sofuoğlu, AysunIn this study, Wood Plastic Composites (WPCs) were produced from post-consumer bulky wastes of recycled plastic and wood in order to minimize waste, decrease environmental effects of plastics, reserve natural resources, and support circular economy for sustainable production and consumption. Five different types of polypropylene (PP) or polyethylene (PE) based recycled plastics and wood obtained from urban household bulky wastes were used in the production of recycled WPC composites, r-WPCs. Virgin WPC (v-WPC) and r-WPC compounds were prepared with wood flour (WF) and maleic anhydride grafted compatibilizer (MAPP or MAPE) to evaluate the effect of recycled polymer type and compatibilizer on the mechanical properties. It was found that tensile strength properties of r-WPCs produced from recycled PP (r-PP) were higher than that of the r-WPCs produced from mixed polyolefins and recycled PE. r-WPCs containing anti-oxidants, UV stabilizers, and compatibilizer with different WF compositions were produced from only recycled garden fraction PP (PPFGF) to determine the optimum composition and processing temperature for pilot scale manufacturing of r-WPCs. Based on tensile, impact, flexural, and water sorption properties of r-WPC compounds with different formulations, the optimum conditions of r-WPC compounds for industrial manufacturing process were determined. Surface morphology of fractured surfaces as well as tensile, flexural and density results of r-WPC compounds revealed the enhancement effect of MAPP on interfacial adhesion in r-WPCs. r-WPC products (crates and table/chair legs) based on bulky wastes were produced using an injection molding process at industrial scale by using 30 wt% WF-filled r-WPC compound. This study demonstrated that r-WPC compounds from recycled bulky plastic and wood wastes can be used as a potential raw material in plastic as well as WPC industry, contributing to circular economy. Graphic