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Groundwater is one of the most important sources of drinking and irrigation water in arid and semi-arid areas. This study aimed to investigate the chemical quality of groundwater for drinking and irrigation, assess the non-carcinogenic risk factors resulting from the concentration of fluoride and nitrate ions, and analyze the sensitivity among children, teenagers, and adults using Monte Carlo method. A total of 171 samples were obtained from confined groundwater in Arsanjan. Among other hydrological parameters of water, EC had the highest average (1135.97). TDS ranged from 67.90 to 1878.30 mg/L, with the lowest and highest total hardness values being 2.90 and 680.8, respectively. The water quality index (WQI) results indicated that 33% of the samples were at the poor water level and the irrigation (IWQI) was less than 25 in 96.36% of the samples, which were categorized as excellent. Thus, the majority of the samples were suitable for irrigation purposes. Additionally, the oral and dermal health risks of fluoride and nitrate were less than 1 in all age groups. Concentration factor was the main indicator in the assessment of the non-carcinogenic risk factors of nitrate and fluoride. The results of sensitivity analysis revealed a reverse relationship with body weight. Further, the results of principal component analysis (PCA) showed a negative relationship between fluoride concentration and pH. Hierarchical cluster analysis also showed that the study variables belonged to three main clusters. Some elements in C1 were also found in the first factor in PCA. The elements in C2 were among the dominant compounds of the groundwater resources of the study area, which may be caused by earth cations or human activities. C3 variables may also be one of the consequences of fertilizer use in areas around groundwater sources., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Nowadays, the presence of humic acid (HA) in water sources is highly regarded due to the production of extremely harmful byproducts such as trihalomethanes. In this study, the effectiveness of an Ag 3 PO 4 /TiO 2 catalyst produced by in situ precipitation as a heterogeneous catalyst for the degradation of humic acid in the existence of visible and solar light was evaluated. The Ag 3 PO 4 /TiO 2 catalyst's structure was characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS), after which the catalyst dosage, HA concentration, and pH parameters were adjusted. After a 20-min reaction, the highest HA degradation of 88.2% and 85.9% in presence of solar light and visible light were attained at the ideal operating conditions of 0.2 g/L catalyst, 5 mg/L HA, and pH 3, respectively. It was discovered that, based on kinetic models, the degradation of HA matched both Langmuir-Hinshelwood and pseudo -first-order kinetics at concentrations of 5 to 30 mg/L (R 2  > 0.8). The Langmuir-Hinshelwood model had surface reaction rate constants ( K c ) of 0.729 mg/L.min and adsorption equilibrium constants ( K L-H ) of 0.036 L/mg. Eventually, a real-water investigation into the process' effectiveness revealed that, under ideal circumstances, the catalyst had a reasonable HA removal efficiency of 56%., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Published by Elsevier Ltd.)