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Öğe Ecological and health risk assessment and quantitative source apportionment of dissolved metals in ponds used for drinking and irrigation purposes(Springer Heidelberg, 2023) Tokatli, Cem; Varol, Memet; Ustaoglu, FikretIn this study, dissolved metal levels of 10 different ponds used as irrigation and drinking water sources in the north of Saros Bay (Turkiye) were evaluated using multivariate statistical methods, contamination and ecological risk indices, and absolute principal component score-multiple linear regression (APCS-MLR). The mean levels of metals in the ponds ranged from 0.045 mu g/L (Cd) to 127 mu g/L (Mn). Pond 7 used for drinking water source had the lowest total metal level. Only Mn levels in two ponds (P1 and P2) slightly exceeded the critical value set by EU Drinking Water Directive. However, the levels of all metals in all ponds were lower than the critical values set for irrigation water and aquatic life. According to the heavy metal pollution index (HPI), five ponds showed low metal pollution in terms of drinking water quality, four ponds showed moderate metal pollution, and one pond (P1) showed moderate to heavy pollution. According to the Nemerow pollution index (NPI) values (0.26-1.82), ponds P1 and P2 showed slight metal pollution, while other ponds showed insignificant metal pollution. Contamination degree (CD) values of ponds varied between 0.95 and 3.33, indicating that all ponds showed low pollution. In terms of irrigation water quality, all ponds showed low or insignificant metal pollution according to the HPI, NPI, and CD values. According to the ecological risk index (ERI) values, metals in all ponds posed low ecological risks for both drinking and irrigation purposes. Factor analysis identified two potential sources: mixed sources and natural sources. The APCS-MLR model results revealed that mixed sources and natural sources contributed 78.99% and 21.01% to dissolved metals in the ponds, respectively. Health risk assessment results indicated that both individual and combined metals in the ponds would not cause non-carcinogenic risks to both adults and children. Similarly, it was found that Cr and As would not cause carcinogenic risks to the residents of the region.Öğe Ecological Risk Assessment of Metals in Sediments from Three Stagnant Water Bodies in Northern Turkey(Springer Heidelberg, 2022) Varol, Memet; Ustaoglu, Fikret; Tokatli, CemPurpose of Review In recent years, anthropogenic activities have caused metal pollution in the sediments of stagnant water bodies, and thus threatening aquatic ecosystems and human health. Therefore, determining the potential ecological risks, contamination degree, and possible sources of metals in sediment of stagnant water bodies is essential for effective management of metal pollution. In this study, we used contamination and risk assessment indices together with multivariate statistics to determine ecological risks and contamination degree of 14 metals in sediments of three important stagnant water bodies (Ladik Lake and Yedikir and Degirmendere dam lakes) in northern Turkey. In addition, the effects of organic matter (OM) and pH on metal accumulation in the sediments were also investigated. Recent Findings The mean contents of Al, V, Mn, Fe, Cu, Zn, and Pb did not differ significantly among the water bodies studied (p > 0.05). The Ladik Lake sediments had significantly lower pH level and higher OM content (p < 0.05). Contamination indices indicated that there was no significant metal contamination in the sediments of all water bodies. Similarly, ecological risk indices indicated that metals posed low ecological risks in the water bodies. According to the sediment quality guidelines, metals would not cause harm to benthic organisms. The accumulation of most metals in the Yedikir Dam Lake was controlled by OM, while the distribution of some metals was affected by both OM and pH in the Degirmendere Dam Lake. According to the factor analysis, all metals in the sediments of the water bodies studied mainly originated from natural sources. The results of this study revealed that sediment contamination indices, ecological risk assessment methods, sediment quality guidelines, and multivariate statistics can be used as effective approaches in determining the environmental and ecological risks and pollution sources of metals in the sediments of stagnant water bodies. Thus, this study can provide important information for the ecological risk assessment and management of metals in the sediments of stagnant water bodies.Öğe Evaluation of the water quality of a highly polluted stream with water quality indices and health risk assessment methods(Pergamon-Elsevier Science Ltd, 2023) Varol, Memet; Tokatli, CemThe water quality of corlu Stream, located in the Thrace region of Turkiye, and exposed to intense industrial pressure, was evaluated by monitoring 10 toxic metals and 13 other water quality variables in the dry and wet seasons of 2021. Seven different water quality indices were applied to determine the pollution level at the sampling stations in the stream. In addition, human health risks from exposure to toxic metals in stream water via ingestion and dermal contact were evaluated. The results showed that the water quality at stations S2 and S3 of corlu Stream receiving domestic and industrial discharges are seriously polluted by NH4-N, PO4-P, COD, BOD5 and suspended solids according to surface water quality standards. In addition, these stations were highly polluted and had poor water quality according to the results of the water quality indices. The average Cr level at station S3 exceeded the permissible levels set for the protection of aquatic life due to effluent discharges from the leather factories. Considering the results of the health risk assessment methods, non-carcinogenic risks from ingestion of combined metals in stream water can be expected at station S3 for both children and adults and at station S2 for children. Also, it was estimated that Cr and As at station S3 may cause carcinogenic health risks for residents.Öğe Metal pollution, eco-health risks and source apportionment in coastal sediments of Samsun, Türkiye: A receiving zone for the Kızılırmak and Yesilırmak rivers(Academic Press Inc Elsevier Science, 2025) Varol, Memet; Ustaoglu, Fikret; Tokatli, CemThis research examined the levels, sources, ecological risks, and health impacts of metal contamination in the coastal sediments of Samsun province, impacted by the Yes,il & imath;rmak and K & imath;z & imath;l & imath;rmak rivers. Surface sediment samples collected from 18 sites representing various land-use types were analyzed for 13 metals (Ba, Cr, Mn, Ni, Co, Sr, Cu, Fe, Zn, Cd, Pb, As and Hg) using inductively coupled plasma mass spectrometry. Spatial assessment results revealed high Cr and Ni concentrations across all sites, primarily due to natural geological formations, while Cd, Pb, Cu, and Hg showed anthropogenic enrichment, particularly at sites near industrial and agricultural areas. Pollution and ecological risk indices as well as sediment quality guidelines (SQGs) were utilized to determine the contamination levels and ecological hazards associated with the metals. Pollution indices (EF, CF, PLI, NPI and MPI) indicated moderate to high pollution levels, mainly driven by Cr and Ni. Ecological risk indices (Er, RI and NRI) showed that Cd posed a moderate risk in sites influenced by industrial and agricultural activities. SQGs-based indices (mERM-Q, TRI and HQc) revealed that some sites exhibited toxic risk potential due to elevated Ni and Cr contents. Health risk assessments highlighted ingestion as the primary exposure pathway and indicated that children were more vulnerable thand adults. The Absolute Principal Component Score-Multiple Linear Regression model discovered three primary sources for metals: natural weathering (21.56 %), anthropogenic activities (32.35 %), and mixed sources (46.09 %). The findings emphasize the importance of determining local background values and sediment quality standards and reinforce the necessity for integrated management strategies to preserve coastal ecosystem health and public safety.Öğe Metals and phosphorus in the sediments of streams emptying into the Çanakkale strait (Dardanelles): Spatial distribution, pollution status, risk assessment and source identification(Academic Press Inc Elsevier Science, 2024) Varol, Memet; Tokatli, CemThe & Ccedil;anakkale Strait is exposed to various pollutants due to its strategic location. It is thought that stream inputs may contribute significantly to metal and phosphorus (P) accumulation in the strait. In this study, the spatial distribution, pollution status, ecological risks and possible sources of twelve metals and P in the sediments of seven important streams emptying into the strait were analyzed. The results showed that Zn (226 mg/kg), Ba (67.2 mg/kg) and Pb (10.4 mg/kg) concentrations were higher in the Umurbey Stream due to mining activities, while P concentration (295 mg/kg) was higher in the & Ccedil;anakkale Stream due to both agricultural activities and domestic wastewater discharges. Modified hazard quotient (mHQ), enrichment factor (EF) and contamination factor (Cf) values revealed that Zn and Pb showed high and moderate contamination in the US3 and US4 sampling sites of the Umurbey Stream, respectively. Similarly, P showed moderate contamination in the & Ccedil;S3 site of the & Ccedil;anakkale Stream. Nemerow pollution index (NPI) showed that the US3 (2.41) and US4 (4.28) sites of the Umurbey Stream were slightly and moderately polluted, respectively. Toxic risk index (TRI) values demonstrated that the sediments in only the US4 site (5.17) of the Umurbey Stream may pose a low toxic risk due to high Zn content. Similarly, based on comparison results with sediment quality guidelines (SQGs), it was found that high Zn content may lead to adverse effects on sediment-dwelling organisms in the US4 site. In addition, the PECquotient value in the US4 site exceeded 0.5, confirming the finding that the sediments in this site could be toxic to benthic organisms. Finally, correlation, cluster and factor analyzes were used to determine possible sources of elements. Mining activities, natural sources and mixed sources (agricultural activities and natural sources) were identified as the main sources of elements in the sediments of the streams. This study can provide an important reference for evaluating stream sediment pollution and managing marine pollution.Öğe Quality Assessment in Terms of Agricultural Water Supply and Macro Element Contents in Water of Çorlu Stream (Thrace Region, Türkiye)(Springer Nature, 2023) Tokatli, Cem; Varol, MemetFreshwater contamination by macro elements because of agrogenic—domestic discharges and threatening almost all the aquatic habitats is a significant global problem today. Çorlu Stream is one of the main components of the Ergene River Basin (sub-basin of Meriç River Watershed). It is also the fluvial ecosystem known to be exposed to the most anthropogenic pressure in the Thrace Region of Türkiye, where has a significant agricultural production potential. In this study, levels of Na, Mg, Ca and K in the water of upstream (Ç1), midstream (Ç2) and downstream (Ç3) of Çorlu Stream were investigated and water qualities were assessed in terms of agricultural use by using Magnesium Rate (MR), Sodium Absorption Rate (SAR), Kelly Index (KI) and Sodium Percentage (Na%). The results indicated that the mean accumulation order of investigated macro elements in water of Çorlu Stream were as follows: Na (183.53 ppm) > K (8.35 ppm) > Mg (6.99 ppm) > Ca (6.13 ppm). The results also showed that the order of locations in terms of irrigation water qualities were as follows: Ç1 > Ç2 > Ç3. The results of applied indices indicated that all of the locations selected on Çorlu Stream were recorded as not suitable for agricultural use. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.Öğe Seasonal dynamics of potentially toxic and essential elements in water of rivers feeding the Çanakkale Strait: a strategic gateway to the Aegean Sea(Springer, 2025) Tokatli, Cem; Ustaoglu, Fikret; Varol, MemetThis study investigated inorganic contamination and associated ecotoxicological, irrigational and health risks in eight fluvial habitats discharging into the & Ccedil;anakkale Strait (& Ccedil;S), analysing twelve potentially toxic (PTEs) and essential (EEs) elements in seasonal surface water samples (2021-2022). Comprehensive water quality (WQI, HPI, NPI, CD, ERI), irrigational suitability (SAR, Na%, MH, KR), and non-carcinogenic/carcinogenic health threats were assessed. Furthermore, multivariate statistical techniques (PCI, PCA, and CA) enabled the identification of probable pollution sources and the classification of potamics. Spatially, Biga Peninsula (BP) streams had higher levels of PTEs, while Gelibolu Peninsula (GP) streams had more EEs. Temporally, dry season concentrations were generally higher. Ecotoxicological and irrigational indices mostly indicated acceptable to moderate contaminated conditions. However, arsenic exposure at Kepez, Hamaml & imath;k and K & uuml;& ccedil;& uuml;k Menderes streams poses both non-carcinogenic and carcinogenic health risks, with CR values far exceeding the safety threshold. PCA identified three distinct pollution sources-geological, industrial, and agricultural-explaining over 81% of the total variance in water quality parameters. CA categorized the region into high, moderate, and low contamination zones, underscoring spatial heterogeneity in water quality.
