Fluoride prevalence in groundwater around a fluorite mining area in the flood plain of the River Swat, Pakistan

Abstract

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.

Evaluation of the Swat River, Northern Pakistan, water quality using multivariate statistical techniques and water quality index (WQI) model

“…Among HM, Pb is one of the most toxic and carcinogenic metals that enter into water bodies from various anthropogenic sources via household, paint, vehicles, and industrial emission (Arain et al 2009). Pb has potential geogenic mafic and ultramafic sources already assessed by many researchers in the study area (Khan et al 2018;Liu et al 2020;Rashid et al 2018). Its toxicity can be seen in a little amount in humans causing disorders in the human nervous system and affecting the digestive as well as the skeletal system.…”

Mapping Groundwater Potential for Irrigation, by Geographical Information System and Remote Sensing Techniques: A Case Study of District Lower Dir, Pakistan

“…Interrelationship of different influencing factors were established (Figure 3) [43], and relative strength, ranks, and weights were assigned [36,44,45]. These parameters were put into GIS platform and score ARC Map 10.2.2 software (Figure 2), and were processed to assigned relative weightage and score, by utilizing multi influencing factor (MIF) techniques, to ensure uniformity [41,46] (Table 1). Seven influential input factors (drainage density (DD), geology (G), land cover, lineament density (LD), rainfall (R), soil type (ST), and topography (slope, TG)) were selected to identify groundwater potential zones.…”

“…It is surrounded by Upper Dir district on the North, Bajaur Agency, and Afghanistan on the West, Malakand Protected Areas towards the South, and the East by Swat district and Upper Dir District (Figure 1). A major river flowing through the study area is Panjkora; however, the most of population use groundwater for agriculture, drinking, and domestic purposes [41].…”

Hydrochemical composition and potentially toxic elements in the Kyrgyzstan portion of the transboundary Chu-Talas river basin, Central Asia

“…and sodium percentage (Na%) 49,55,56 was used for assessing the irrigation suitability of river waters. Piper diagrams [57][58][59] , Gibbs diagrams [60][61][62][63][64] , and mixing diagrams [65][66][67] were used to determine influences of the river hydrochemistry. By using the software Phreeqc Interactive 3.6.2 with database file (minteq.v4.dat) 68 , chemical speciation modeling was conducted with major ions and the whole potentially toxic elements.…”