Appraisal of heavy metal contents, spatial-temporal variation, toxic metal pollution, and health risk in water and sediment of Uluabat Lake (Ramsar Site, Turkey).

Uluabat Lake holds a significant status as one of our country's essential Ramsar areas. Nevertheless, the lake faces considerable pressure from environmental pollutants. This study employed GIS-based index methods to examine the heavy metal pollution and water quality in Uluabat Lake. To achieve this, sediment and water samples were collected from 19 different locations during various seasons. The concentrations of As, Ni, Cr, Zn, Cu, Cd, Pb, Hg, Al, Fe, and Mn in these samples were analyzed. The average contents of the investigated heavy metals in the lake waters were found to be in the following order: Al > Fe > Mn > As > Zn > Ni > Pb > Cu > Cr > Hg > Cd. The As content in the lake waters exceeded the limit value of 10 µg/L, as defined by TS-266 (2005) and WHO (2017) guidelines. Consequently, the lake waters were deemed unsuitable for drinking. The health risk assessments revealed that consuming the lake waters could lead to both carcinogenic and non-carcinogenic health problems. However, all other metal concentrations were measured below the specified limit values. Based on index calculations, the heavy metal pollution index value indicated that the lake water samples were suitable for drinking water use. Additionally, all samples fell into the "low pollution" category according to the heavy metal evaluation index, and degree of contamination values. However, geoaccumulation index values indicated that As was moderately contaminated. Moreover, enrichment factors of As, Cr, Ni, Pb, and Cd exhibited significant enrichment in lake sediments, with pollution load index values of all sediment samples indicating the impact of anthropogenic pollutants and a decline in sediment quality. Considering all the obtained results together, it can be concluded that environmental pollutants, especially heavy metal pollution, primarily enter the lake water through stream transports, leading to pollution in Uluabat Lake.

Assessment of heavy metal pollution and quality in lake water and sediment by various index methods and GIS: A case study in Beysehir Lake, Turkey.

Beysehir Lake, Turkey's largest freshwater lake, is also a "Drinking Water Reserve". In the study, heavy metal (As, Cr, Cu, Ni, Zn, Pb, Cd, Hg, Fe, Al, Mn) concentrations of seasonal lake water and bottom sediment samples were determined to evaluate the heavy metal pollution. Several index methods were applied, and pollution assessments were made using the obtained analysis results of lake water and sediment samples. The average concentrations of the heavy metals in the lake waters are observed as Fe > Al > Mn > As>Zn > Ni > Pb > Cr > Cu > Hg > Cd. When the lake waters were compared with the TS 266 (2005) and WHO (2017) limit values, it was determined that lake waters are below the limit values in terms of the heavy metals. According to index results, all of the lake samples are suitable for use as drinking water in accordance with the heavy metal pollution index (HPI) value, all of the samples are in the "low pollution" class in accordance with the heavy metal evaluation index (HEI) and degree of contamination (Cd) values. In addition, the water average concentrations of the heavy metals in the lake sediments are observed as Fe > Al > Mn > Cr > Ni > Zn > Cu > As>Pb > Cd > Hg. The contamination factor (CF) and enrichment factor (EF) revealed that sediments were considerably and moderately polluted by As, Cr, Cu, Ni, Cd, Fe and Mn and low polluted and/or unpolluted by other metals. The calculated pollution load index (PLI) and Igeo values indicate that lake sediments do not carry a risk of heavy metal contamination.

Appraisal of groundwater quality with WQI and human health risk assessment in Karamik wetland and surroundings (Afyonkarahisar/Turkey).

Groundwater in Karamik wetland and surroundings, which is one of the important wetlands in Turkey, was examined and the chemical properties and quality of groundwater were determined in the present study. In addition, the possible risks to human health as a result of groundwater usage were investigated along with spatial analyses carried out using Geographic Information Systems (GIS). Physicochemical analyses were carried out on 25 samples taken from groundwater. The dominant ions in the study area are Ca, Mg, and HCO3. When the results are compared with the limit values in the valid drinking water guidelines such as TSI-266 (Standards for drinking waters, 2005) and WHO (Guidelines for drinking-water quality, 2011), the groundwaters were not suitable for use as drinking water in terms of NO3, Fe, Pb and As. The analysis results were evaluated together with GIS and Water Quality Index (WQI) methods. In the evaluations with the WQI method, 76% of the samples were in the "poor water" class. The groundwater in the study area is polluted by both geogenic and anthropogenic sources. For this reason, health risk assessment was performed due to the use of groundwater in the region by the local people in different areas, especially as drinking water, and the negative effects of water quality. Accordingly, there are non-carcinogenic negative effects on health in terms of NO3, As, Pb and Fe parameters from the use of groundwater by children. In addition, Pb and As concentrations are at carcinogenic levels for both children and adults in all groundwater samples collected from the study area. Therefore, it is not recommended to use groundwater as drinking water without treatment.

Appraisal of groundwater pollution risk by combining the fuzzy AHP and DRASTIC method in the Burdur Saline Lake Basin, SW Turkey.

To ensure sustainable groundwater management, water resources must be protected in terms of quantity and quality. In this context, it is important to reveal the potential of existing groundwater resources to be affected by environmental and/or geogenic pollutants. In the present study, groundwater vulnerability assessment was performed using DRASTIC model by fuzzy AHP and GIS integration for Burdur Saline Lake basin, SW Turkey. In addition, validation and sensitivity analyses were performed in the study. Weight and rating values assigned for DRASTIC parameters and sub-parameters were determined by fuzzy AHP method, and these values were used in GIS analyses. In the validation analysis of the obtained groundwater vulnerability map, NO3 ion was considered since the agricultural activities are intense in the study area. In addition, sensitivity analyses were performed to determine the most effective parameter. According to the obtained results, 26.43% of the study area was determined as the highly vulnerable areas, while 11.44 and 62.13% were moderate vulnerable and low vulnerable, respectively. Impact of the vadose zone, depth to water table, and net recharge parameters were determined as more effective than other parameters. The nitrate concentrations of the groundwater in the region confirm the vulnerability map obtained by the study. Therefore, it is recommended to take realistic and urgent protection measures aimed at sustainable use of groundwater in highly vulnerable areas.

Assessment of groundwater quality and human health risk related to arsenic using index methods and GIS: A case of Suhut Plain (Afyonkarahisar/Turkey).

In this study the spatial variation of groundwater quality and the potential health risk situation arising were evaluated determining Water Quality Index (WQI and IWQI) for drinking and irrigation water in Suhut Plain (Afyonkarahisar, Turkey). A total of 27 groundwater samples were collected from wells in May-2019 and physicochemical analysis results were evaluated. According to analysis results of the water samples, the orders of anion and cations are HCO3>SO4-2>Cl- > CO3-2 and Ca+2 > Mg+2 > Na+>K+, respectively. It has been determined that groundwater samples are generally in "excellent" and "good" water class according to the WQI and IWQI assessment. At the same time, groundwater in the study area is suitable for agricultural irrigation water. However, many water samples cannot be used as drinking water in terms of TDS, Mg, NO3 and AsT according to limit values of TSI-266 (2005) and WHO (2011). Health risk assessment indicate that, the risk of developing cancer due to arsenic exposure in healthy adults or children is very low. But, arsenic has a high non-carcinogenic and carcinogenic potentially harmful effect.

Assessment of groundwater quality and usability of Salda Lake Basin (Burdur/Turkey) and health risk related to arsenic pollution.

PURPOSE: In this study the aim was to analyze the seasonal concentration, groundwater quality, usage areas and arsenic-related health risk of major ions and heavy metals in groundwater samples collected from the Salda Lake basin. METHODS: In this study, 42 groundwater samples were collected from springs and wells in dry and wet seasons in 2015. Hydrogeochemical evaluations were made using different diagrams such as Piper and Gibbs diagrams. Groundwater quality was determined by the water quality index method (WQI) and different diagrams. Finally, health risk assessments related to arsenic were performed. RESULTS: The dominant water types are Mg-Ca-HCO3 and Mg-HCO3 in the wet season and Mg-HCO3 and Mg-HCO3-CO3 in the dry season. According to calculated WQI values ranged from 24.14 to 56.93 in the wet season ranged from 25.27 to 145.87 in dry season. This situation indicates that the quality of water samples is mostly good both seasons. AsT concentrations were between 2.1-6.3 µg/L in the dry season and 2.9-10.5 µg/L in the wet season. The risk of developing cancer due to arsenic exposure in healthy adults or children is very low. But arsenic has high non-carcinogenic and carcinogenic potentially harmful effect in the study area. In addition, water samples are not appropriate for use as drinking water in terms of fertilizers and trace element concentrations. Also, MH will be an important problem in waters that will be used as irrigation water. The use of some samples is not recommended as it may cause crusting on metal surfaces in industrial areas. CONCLUSIONS: According to the results obtained, the quality of groundwater in the study area should be monitored and the usage areas should be determined accordingly.

Evaluation of sustainable groundwater utilization using index methods (WQI and IWQI), multivariate analysis, and GIS: the case of Aksehir District (Konya/Turkey).

Aksehir district is one of the regions where significant agricultural production and industrial activities are carried out. Groundwater is the most important water resource in this region used for different purposes, especially for drinking and irrigation water. In order to ensure sustainable water management in the study area, it is necessary to reveal the drinking and irrigation water quality of groundwater and to take precautions and determine the management plans. In the present study, groundwater quality was evaluated using water quality index methods (WQI and IWQI) and statistical analyses to determine the sustainable and most appropriate usage of groundwater. In addition, spatial distribution maps were prepared using GIS for drinking and irrigation WQI assessments of the groundwater. A total of 31 groundwater samples were collected from wells in October 2018 and physicochemical analysis results were evaluated. According to the results obtained with the WQI method, all groundwater samples in the study area are definitely not suitable for use as drinking water. According to the results obtained by the IWQI method, samples S23, S24, S25, S27, S28, S29, and S31 especially are not suitable for use as irrigation water. Statistical evaluations support the results obtained from WQI and IWQI methods. Also, factor analysis indicates that anthropogenic pollution, especially agricultural applications, is effective on the chemical and quality characteristics of groundwater samples in addition to the geological properties. As seen in the spatial distribution maps for WQI and IWQI results, while the quality of groundwaters around Dogruözü and Erdogdu is not suitable for drinking water, the groundwater quality in the north-east of the study area is also unusable for irrigation water. Consequently, the use of groundwater in the region as drinking water can be dangerous for human health and alternative drinking water resources should be investigated. In addition, in order to ensure the sustainable use of groundwater, it is necessary to control agricultural activities in the region, to monitor the use of pesticides and fertilizers, and to encourage organic farming practices in the region.

Hydro-chemical and microbiological pollution assessment of irrigation water in Kizilirmak Delta (Turkey).

The Kizilirmak Delta is one of the most important agricultural production regions and it was included as part of the Ramsar Convention in 1998. The water used in agricultural irrigation is mostly supplied from drainage channels. In the present study, 120 water samples were collected from drainage channels and analyzed to characterize the groundwater chemistry and microbiological contamination. Sea water interface, discharge of sewage, wastewater from agricultural activities and livestock and uncontrolled solid waste landfills were identified as the most important pollutant sources in the delta. Serious microbiological pollution was detected in channel water samples. These results indicate that sewage waters mix with the channel waters in the delta. Also, the correlations of parameters such as EC, TDS, DO, Cl- and SO42- indicate that channel waters contain high dissolved minerals. It was concluded that especially agricultural pollution and waste water affects water resources negatively in the region.

Assessment of water quality and hydrogeochemical processes of Salda alkaline lake (Burdur, Turkey).

Salda Lake is one of the rare alkaline lakes in the world. In this study, the major and trace element contents of the Salda Lake water were analysed in two periods. Lake water samples were taken at the surface, at 10 m and 20 m depths. The pH and EC values of the lake water varied from 9.08 to 9.34 and from 1690 to 2124 µS/cm, respectively. The dominant water type of the lake water was Mg-CO3-HCO3. The high Mg content in the lake water originated from the weathering of ultramafic rocks which were located in the lake basin. All of the Ca, Cl and SO4 contents were high in surface samples in the dry period. The CO3 and HCO3 contents of the lake water did not show a change with depth and were constant in the wet period. The Mg, Na and K contents of the lake water increased depending on the depth in both periods, while CO3 and HCO3 contents showed depth-dependent increases only in the dry period. Weathering processes and anthropogenic inputs are the largest dissolution mechanisms that control the chemical structure of the lake water. The Salda Lake water is generally classified as class I in terms of T, DO, oxygen saturation, NH4 and NO2 parameters according to the SWQR and USEPA regulations. But, the water is in classes II, III, IV and V with respect to pH, EC, NO3, biochemical oxygen demand (BOD), oxygen saturation, As and Cr in the different periods. The increase in the As and Cr concentrations is geogenic in origin and is related to the lithological units that interact with the bottom and surroundings of the lake.

Assessment of groundwater quality and health risk in drinking water basin using GIS.

Egirdir Lake basin was selected as the study area because the lake is the second largest freshwater lake in Turkey and groundwater in the basin is used as drinking water. In the present study, 29 groundwater samples were collected and analyzed for physico-chemical parameters to determine the hydrochemical characteristics, groundwater quality, and human health risk in the study area. The dominant ions are Ca2+, Mg2+, HCO32-, and SO42. According to Gibbs plot, the predominant samples fall in the rock-water interaction field. A groundwater quality index (WQI) reveals that the majority of the samples falls under good to excellent category of water, suggesting that the groundwater is suitable for drinking and other domestic uses. The Ca-Mg-HCO3, Ca-HCO3, Ca-SO4-HCO3, and Ca-Mg-HCO3-SO4 water types are the dominant water types depending on the water-rock interaction in the investigation area. Risk of metals to human health was then evaluated using hazard quotients (HQ) by ingestion and dermal pathways for adults and children. It was indicated that As with HQ ingestion >1 was the most important pollutant leading to non-carcinogenic concerns. It can be concluded that the highest contributors to chronic risks were As and Cr for both adults and children.

Evaluation of water quality using water quality index (WQI) method and GIS in Aksu River (SW-Turkey).

The aim of this study is evaluate water quality of the Aksu River, the main river recharging the Karacaören-1 Dam Lake and flowing approximately 145km from Isparta province to Mediterranean. Due to plan for obtaining drinking water from the Karacaören-1 Dam Lake for Antalya Province, this study has great importance. In this study, physical and chemical analyses of water samples taken from 21 locations (in October 2011 and May 2012, two periods) through flow path of the river were investigated. The analysis results were compared with maximum permissible limit values recommended by World Health Organization and Turkish drinking water standards. The water quality for drinking purpose was evaluated using the water quality index (WQI) method. The computed WQI values are between 35.6133 and 337.5198 in the study. The prepared WQI map shows that Karacaören-1 Dam Lake generally has good water quality. However, water quality is poor and very poor in the north and south of the river basin. The effects of punctual and diffuse pollutants dominate the water quality in these regions. Furthermore, the most effective water quality parameters are COD and Mg on the determination of WQI for the present study.

Determination of canal orifice co-ordinates and MB2 incidence of maxillary first molars in a Turkish sub-population.

OBJECTIVES: To measure the co-ordinates of the root canal orifices and to determine the incidence of mesiobuccal-2 (MB2) in maxillary first molars in a Turkish sub-population. MATERIALS AND METHODS: Standard digital photographs were taken under a stereomicroscope from the occlusal aspect of each tooth (n = 176) before and after crown removal. Canal orifices were negotiated under moderate magnification using dental loupes. The coordinates of the orifices and the distances of each from the central fossa were measured by using geographic software. Intensity maps of the orifice locations were created by using the co-ordinates of all canal orifices. A representative map was drawn using the mean values of orifice locations and access projection area. RESULTS: In the right maxillary first molars, the mean values for the (X, Y) co-ordinates were (0.67, 2.68) for mesiobuccal-1 (MB1), (0.81, 0.84) for MB2, (-1.12, 1.26) for distobuccal-1 (D1), (-0.89, 0.23) for distobuccal-2 (D2) and (0, -2.50) for palatinal (P); the corresponding mean values in the left maxillary first molars were (-0.78, 2.56), (-0.98, 0.90), (0.99, 1.18), (0.69, 0.78) and (0.00, -2.53), respectively. The average MB1-MB2 distance was 1.97 mm. Distobuccalcanal orifices were localized at the distal side of the center in 98.3% of teeth. The incidence of MB2 was 46.02%. CONCLUSIONS: The distobuccal canal orifice is mostly located on the distal side of the central fossa. Thus, it should be considered that the access cavity of the maxillary molars may not be always limited mesially. The incidence of MB2 in this sub-population was 46.02%, which is of great importance clinically.

Solid waste disposal site selection with GIS and AHP methodology: a case study in Senirkent-Uluborlu (Isparta) Basin, Turkey.

The appropriate site selection for waste disposal is one of the major problems in waste management. Also, many environmental, economical, and political considerations must be adhered to. In this study, landfill site selection is performed using the Geographic Information System (GIS), the Analytical Hierarchy Process (AHP), and the remote sensing methods for the Senirkent-Uluborlu Basin. The basin is located in the Egirdir Lake catchment area, which is one of the most important fresh water in Turkey. So, waste management must be regulated in the basin. For this aim, ten different criteria (lithology, surface water, aquifer, groundwater depth, land use, lineaments, aspect, elevation, slope, and distance to roads) are examined in relation to landfill site selection. Each criterion was identified and weighted using AHP. Then, each criterion is mapped using the GIS technique, and a suitability map is prepared by overlay analyses. The results indicate that 96.3% of the area in the basin is unsuitable; 1.6%, moderately suitable; and 2.1%, most suitable. Finally, suitable regions in the basin are determined for solid waste landfill disposal and checked in the field. The selected and investigated regions are considered to be suitable for the landfill.

Combining AHP with GIS for landfill site selection: a case study in the Lake Beysehir catchment area (Konya, Turkey).

Landfills are the most common method for the disposal of municipal solid waste (MSW) in Turkey. However, determining the location of landfill sites is a difficult and complex process because it must combine social, environmental and technical parameters. Additionally, it depends on several criteria and regulations. The main objective of this study was to select of a landfill site for the Lake Beysehir catchment area. The Beysehir Lake is the largest freshwater lake and drinking water reservoir in Turkey, but there is no controlled landfill site in the region. Therefore, the landfill site should be determined such that the lake is protected. To determine the most suitable landfill site, an analytical hierarchy process (AHP) was combined with a geographic information system (GIS) to examine several criteria, such as geology/hydrogeology, land use, slope, height, aspect and distance from settlements, surface waters, roads, and protected areas (ecologic, scientific or historic). Each criterion was evaluated with the aid of AHP and mapped by GIS. Data were assorted into four suitability classes within the study area, i.e., high, moderate, low and very low suitability areas, which represented 3.24%, 7.55%, 12.70% and 2.81%, of the study area, respectively. Additionally, 73.70% was determined to be completely unsuitable for a landfill site. As a result, two candidate landfill sites are suggested and discussed. The final decision for landfill site selection will require more detailed field studies.