RESUMO
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.
RESUMO
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.
