This study investigated the fluoride (F) concentrations and physicochemical parameters of the groundwater in a fluorite mining area of the flood plain region of the River Swat, with particular emphasis on the fate and distribution of F and the hydrogeochemistry. To better understand the groundwater hydrochemical profile and F enrichment, groundwater samples (n=53) were collected from shallow (24-40m), mid-depth (48-65m) and deep (85-120m) aquifers, and then analysed using an ion-selective electrode. The lowest F concentration (0.7mg/L) was recorded in the deep-aquifer groundwater, while the highest (6.4mg/L) was recorded in shallow groundwater. Most groundwater samples (62.2%) exceeded the guideline (1.5mg/L) set by the World Health Organization (WHO); while for individual sources, 73% of shallow-groundwater samples (F concentration up to 6.4mg/L), 42% of mid-depth-groundwater samples, and 17% of deep-groundwater samples had F concentrations that exceeded this permissible limit. Assessment of the overall quality of the groundwater revealed influences of the weathering of granite and gneisses rocks, along with silicate minerals and ion exchange processes. Hydrogeochemical analysis of the groundwater showed that Na is the dominant cation and HCO the major anion. The anionic and cationic concentrations across the entire study area increased in the following order: HCO>SO>Cl>NO>F>PO and Na>Ca>Mg>K, respectively. Relatively higher F toxicity levels were associated with the NaHCO water type, and the chemical facies were found to change from the CaHCO to (NaHCO) type in calcium-poor aquifers. Thermodynamic considerations of saturation indices indicated that fluorite minerals play a vital role in the prevalence of fluorosis, while under-saturation revealed that - besides fluorite minerals - other F minerals that are also present in the region further increase the F concentrations in the groundwater. Finally, a health risk assessment via Dean's classification method identified that the groundwater with relatively higher F concentrations is unfit for drinking purposes.

This study evaluates the characteristics of water along the Swat River, Northern Pakistan. For this purpose, water samples (n = 30) were collected and analyzed for physicochemical parameters including heavy metals (HM). The mean concentrations of physicochemical parameters and HM were within the drinking water guideline values set by the World Health Organization (WHO 2011) except 34%, 60%, and 56% of copper (Cu), nickel (Ni), and lead (Pb), respectively. Pollution sources were identified by various multivariate statistical techniques including correlation analysis (CA) and principal component analysis (PCA) indicating different origins both naturally and anthropogenically. Results of the water quality index (WQI) ranged from 13.58 to 209 with an average value of 77 suggesting poor water quality for drinking and domestic purposes. The poor water quality was mainly related to high sodium (alkalinity) and salinity hazards showing > 27% and 20% water samples have poor alkalinity and salinity hazards, respectively. Hazard quotient (HQ) and hazard index (HI) were used to determine the health risk of HM in the study area. For water-related health risk, HQingestion, HQdermal, and HI values were > 1, indicating noncarcinogenic health risk (NCR) posed by these HM to the exposed population.

Purpose The current study was carried out in Gadoon Amazai industrial estate and surrounding areas in order to investigate environmental pollution resulted from various industries. The industries flush their effluents in the surrounding areas without treatment, which can contribute toxic elements and compounds to the soil and also to groundwater of nearby areas. The toxic metals have high potential ecological risk to surrounding environment. Materials and methods A continuous field survey was conducted to find out flow of industrial effluent in surrounding area. For determining major and toxic metals in soil, a random sampling technique was followed to collect representative samples. A total of 45 samples were collected with 25 soil samples from target areas and 20 samples from the reference areas. For the toxic and heavy metals, 1 g powder soils (−200 mesh size) was treated with hydrofluoric acid (10 ml), aqua regia (20 ml), and HCl (20 ml). For the major elements, 0.5 g samples was treated with hydrofluoric acid (10 ml) and perchloric acid (4 and 2 ml with 2-h interval). All these soil samples were analyzed for 13 major and toxic metals using Perkin Elmer atomic absorption spectrophotometer (AAS-700) equipped with graphite furnace (GF). Results and discussion The results showed that the mean concentrations (mg/kg) of toxic, heavy, and major elements in target area are

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