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The present study found that ~80 million people in India, ~60 million people in Pakistan, ~70 million people in Bangladesh, and ~3 million people in Nepal are exposed to arsenic groundwater contamination above 10 µg/L, while Sri Lanka remains moderately affected. In the case of fluoride contamination, >120 million in India, .2 million in Pakistan, and ~0.5 million in Sri Lanka are exposed to the risk of fluoride above 1.5 mg/L, while Bangladesh and Nepal are mildly affected. The hazard quotient (HQ) for arsenic varied from 0 to 822 in India, 0 to 33 in Pakistan, 0 to 1,051 in Bangladesh, 0 to 582 in Nepal, and 0 to 89 in Sri Lanka. The cancer risk of arsenic varied from 0 to 1.64× 1-1 in India, 0 to 1.07 × 10-1 in Pakistan, 0 to 2.10 × 10-1 in Bangladesh, 0 to 1.16 × 10-1 in Nepal, and 0 to 1.78 × 10-2 in Sri Lanka. In the case of fluoride, the HQ ranged from 0 to 21 in India, 0 to 33 in Pakistan, 0 to 18 in Bangladesh, 0 to 10 in Nepal, and 0 to 10 in Sri Lanka. Arsenic and fluoride have adverse effects on animals, resulting in chemical poisoning and skeletal fluorosis. Adsorption and membrane filtration have demonstrated outstanding treatment outcomes. [ABSTRACT FROM AUTHOR]

Purpose: Water pollution is a concern that harms aquatic ecosystems and has economic and social consequences. Over the years, industrial, agricultural, and municipal activities have contributed to the deterioration of water quality, raising concerns among researchers about its impact on society. The River Kabul in Pakistan faces pollution challenges, including Fluoride contamination. However, more is needed to know about how this affects tourism in the area. Therefore, this study aims to contribute to existing knowledge by examining the influence of contamination on tourism activities in the River Kabul region. Aquatic fluoride contamination is currently an issue with toxicological implications. Methods: A mix method Approach was applied to gather information to know the water quality and its impact on local fishermen livelihood and tourism, before that water samples were collected to identify the level fluoride selective sampling techniques is outlined. The respondents were selected from tourist spots along the river Kabul for interviews. Results: The study uncovered findings and outcomes. Firstly it revealed that water pollution in River Kabul had a effect on domestic tourism activities in Pakistan. Tourists were discouraged from participating in water related activities like swimming and boating due to the water containing high levels of fluoride. Conclusions: The research findings have shown that the river is facing problems, with water pollution and high levels of fluoride. These issues are having an impact on tourism as the poor water quality, caused by pollutants like heavy metals organic matter and microbial contamination is leading to a decrease in the number of tourists visiting the region. This decline in tourism is causing losses for the area. Moreover the presence of pollution not affects tourists but also poses health risks to local residents making it even more discouraging for people to engage in tourism activities. [ABSTRACT FROM AUTHOR]

Consumption of high fluoride (F−) and nitrate (NO3−) containing water may pose serious health hazards. One hundred sixty-one groundwater samples were collected from drinking wells in Khushab district, Punjab Province, Pakistan, to determine the causes of elevated F− and NO3− concentrations, and to estimate the human health risks posed by groundwater contamination. The results showed pH of the groundwater samples ranged from slightly neutral to alkaline, and Na+ and HCO3− ions dominated the groundwater. Piper diagram and bivariate plots indicated that the key factors regulating groundwater hydrochemistry were weathering of silicates, dissolution of evaporates, evaporation, cation exchange, and anthropogenic activities. The F− content of groundwater ranged from 0.06 to 7.9 mg/L, and 25.46% of groundwater samples contained high-level fluoride concentration (F− > 1.5 mg/L), which exceeds the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines of drinking-water quality. Inverse geochemical modeling indicates that weathering and dissolution of fluoride-rich minerals were the primary causes of F− in groundwater. High F− can be attributed to low concentration of calcium-containing minerals along the flow path. The concentrations of NO3− in groundwater varied from 0.1 to 70 mg/L; some samples are slightly exceeding the (WHO Guidelines for drinking-water quality: incorporating the first and second addenda, WHO, Geneva, 2022) guidelines for drinking-water quality. Elevated NO3− content was attributed to the anthropogenic activities revealed by PCA analysis. The high levels of nitrates found in the study region are a result of various human-caused factors, including leaks from septic systems, the use of nitrogen-rich fertilizers, and waste from households, farming operations, and livestock. The hazard quotient (HQ) and total hazard index (THI) of F− and NO3− showed high non-carcinogenic risk (> 1) via groundwater consumption, demonstrating a high potential risk to the local population. This study is significant because it is the most comprehensive examination of water quality, groundwater hydrogeochemistry, and health risk assessment in the Khushab district to date, and it will serve as a baseline for future studies. Some sustainable measures are urgent to reduce the F− and NO3− content in the groundwater. [ABSTRACT FROM AUTHOR]

This study presents a comparison among different-bottled drinking water commercially available in Lahore Pakistan. For that, five locally produced drinking water brands and four national brands were selected. Different physical, chemical and microbiological parameters like EC, pH, salinity, TDS, Na+, K+, Ca2+, Mg2+, Cl−, F−, Fe3+, SO42-, NO3-, PO43-, Arsenic (As), total coliforms and faecal coliforms/Escherichia coli were analysed. Results showed that there was a remarkable difference in the quality. Analysed data exposed that EC range was 141–298.3 μS/cm, pH 7.35–7.95, Salinity 0.1 ± 0.02 ppt, turbidity 2.13–2.45 NTU, TDS 85–182 mg/L, sodium 12–71.2 mg/L, potassium 0.1–2.4 mg/L, calcium 16–40 mg/L, mag- 30 magnesium 2.5–35 mg/L, chloride 35–95 mg/L, fluoride 0.29–0.94 mg/L,Iron below detectable limits to 0.17 mg/L, sulphate s 22–120 mg/L, phosphates 0.023–0.17 mg/L, nitrates 0.9–3.6 mg/L and arsenic were 0.0005–0.01 mg/L in these brands of drinking water. The analysed data was compared with the PSQCA, US–EPA and WHO standards. In only one brand of water, the concentration of sodium (71.2 mg/L) and arsenic (0.01 mg/L) was higher than permissible limits. For microbiological contamination brand E (80 colonies/100 mL sample), C (25 colonies/100 mL sample), S (100 colonies/100 mL sample) and K (15 colonies/100 mL sample) were.Some of these water brands examined were deficient in essential minerals like S brand in which Magnesium was only 2.5 mg/L and K and G brands in which calcium was 16 mg/L and 20 mg/L, respectively It was observed that treatment plants having raw water of low TDS 60 or those whose process based on 50% mineral dosing and 50% blending were cost-effective. Data presented in this study are important because it can be considered as baseline data for future. [ABSTRACT FROM AUTHOR]

Arsenic (As), and fluoride (F−) are potent contaminants with established carcinogenic and non-carcinogenic impacts on the exposed populations globally. Despite elevated groundwater As and F− levels being reported from various regions of Pakistan no biomonitoring study has been reported yet to address the co-exposure impact of As and F− among school children. We aimed to investigate the effects of these two contaminants on dental fluorosis and intelligence quotient (IQ) along with the induction of oxidative stress in rural children under co-exposed conditions. A total of 148 children (5 to 16 years old) from the exposed and control group were recruited in the current study from endemic rural areas of Lahore and Kasur districts, Pakistan having elevated As and F− levels in drinking water than permissible limits. We monitored malondialdehyde and its probable association with antioxidants activity (SOD, CAT, and GR) as a biomarker of oxidative stress. GSTM1/T1 polymorphisms were measured to find the impact of As on health parameters. Mean urinary concentrations of As (2.70 vs. 0.016 µg/L, P < 0.000) and F− (3.27 vs. 0.24 mg/L, P < 0.000) as well as the frequency of dental fluorosis were found elevated among the exposed group. The cases of children with lower IQ were observed high in the exposed group. Additionally, lower concentrations of antioxidants (SOD, CAT, and GR) were found suggesting high susceptibility to F− toxicity. The findings suggest that F− accounted for high variations in health parameters of children under the co-exposure conditions with As. [ABSTRACT FROM AUTHOR]

The aim of the work was to determine the role of bacteria to mitigate the effect of fluoride on the growth, gas exchange characteristics, and productivity of the two wheat varieties (Galaxy-13, Chakwal-50). Experiment was conducted in the Botanical Garden (University of the Punjab, Lahore Pakistan) according to the Design Expert software 11. Four concentrations of NaF (0 ppm, 150 ppm, 250 ppm, and 350 ppm) and three bacterial strains (ss5a, ss5b, and ss10a) were used. Growth parameters, gas exchange characteristics, fresh and dry weight of root and shoot, and productivity were measured. The results observed were less harmful in case of plants treated in combination with NaF+bacteria as compared to plants treated with NaF alone. Fluoride affected various parameters, chlorosis, leaf tip burn, leaf necrosis, growth, and productivity of the wheat plants. Galaxy-13 was least influenced by F compared to the Chakwal-50 variety. It was concluded that growth was increased with the application of beneficial fluoride resistant bacteria and proved helpful in minimizing the harmful effects of fluoride salt on wheat varieties. [ABSTRACT FROM AUTHOR]

An excess of the fluoride ion (F-) above the recommended upper limit, such as the WHO recommended upper limit of 1.5 mgL-1, may cause fluorosis in humans, as reported in several countries, e.g. Pakistan, China, and India. Various commercial adsorbents has been used for F-removal from water but there is still a desire for an environmentally friendly and economic adsorbent. Therefore, a novel adsorbent, i.e. Dodonaea bark biochar (DBBC) was prepared, from Dodonaea viscosa under pyrolysis at 750 °C in an inert atmosphere, to remove excessive F-from water and studied with batch experiments involving a number of parameters: pH (2-10), contact-time (5-145 minutes), dosage of adsorbent (1-7 g/50 mL), and initial F-concentration (2-10 mgL-1). The biochar showed 90% F-removal in the acidic range and 60% removal at neutral pH under optimized conditions. In conclusion, the adsorbent DBBC is recommended as an inexpensive sorbent material for F-contaminated water. [ABSTRACT FROM AUTHOR]

Using bibliometrics enables the identification of hotspots in the literature and the discovery of patterns in science. The study was carried out to systematically analyze the published articles on fluoride (F) research from September 2011 to 2020 via the Scopus database, which turned out 1,006 records of research articles after specifying the search parameters. Bibexcel and VOS viewer was used to examine and illustrate the data. A total of 46 countries were highlighted which published the highest number of articles; among them, India was on the top with 193 research articles, followed by China (89), the USA (26), Pakistan (43), and Iran (31). The unexpected overall expansion in the distribution of F-related research from 2015 to 2020 is evident proof of the rising issue of worldwide F tainting. Southeast Asian countries, viz India, Pakistan, Bangladesh, and Iran, seem more prone to fluoride contamination in drinking water. A potential reason for the increase is an increasing number of cases of dental and skeletal fluorosis. [ABSTRACT FROM AUTHOR]

Litho-geochemical characteristics of low and high fluoride (F−) groundwater along with hydrological processes were investigated to delineate its genesis and enrichment mechanism in a watershed sedimentary basin. In this study, groundwater F− concentration ranged from 0 to 20 mg/L with a mean and standard deviation of 2.8 and ± 3.7 mg/L, respectively. Out of N = 87, 63% of samples exceeded the World Health Organization (WHO) limit of 1.5 mg/L. The order of cationic and anionic dominance in groundwater samples with mean was found in decreasing order as Na+ > Mg2+ > Ca2+ > K+ and HCO3− > SO42− > Cl− > PO43− > NO3− measured in milligrams per liter. Groundwater chemistry changed from Ca-HCO3 to Na-HCO3 type and low to high fluoride as we moved from mountain foot towards the synclinal basin. Low fluoride groundwater reflected weathering, recharge, and reverse ion exchange processes with Ca–HCO3– and Ca–Mg–Cl–type water while high fluoride groundwater revealed base ion exchange, mixing, and desorption as dominant hydrological processes with Na-HCO3 and Na-Cl types of water. Gibb's diagram showed rock weathering and mineral dissolution as the major geochemical processes controlling water chemistry with an insignificant role of evaporation in the semi-arid area. Fluoride was undersaturated with mineral fluorite, indicating fluoride in groundwater is released by secondary minerals. However, due to complex geological features, groundwater fluoride enrichment was affected by a broad-scale process across a wide area such as depth, residence time, and most important geomorphological units hosting the aquifer. [ABSTRACT FROM AUTHOR]

The main objective of this study was to estimate the drinking water quality and public health assessment due to nitrate, nitrite and fluoride contaminations in Ahmadpur East, Punjab, Pakistan. Thirty-six drinking water samples were collected in the study area. Concentrations of geo-chemical parameters (pH, TDS and EC), nitrate, nitrite and fluoride were examined. The mean values of concentrations of nitrate, nitrite and fluoride were found 0.4197, 0.006 and 0.67 mg/L, respectively. Mean values of potential of hydrogen (pH), total dissolved solid (TDS) and electrical conductivity (EC) were found 7.28, 630 ppm and 1257 μS/cm, respectively. Health risk assessment was estimated by chronic daily intake (CDI), hazard quotient (HQ) and Total Health Index (THI) due to fluoride, nitrate and nitrite for infants, children, teenagers and adults. The CDI and HQ of fluoride estimated greater permissible limit in different age groups than nitrite and nitrate in urban region of the study area. THI in infant and children determined higher than other age groups in the urban region. The infant and children suffer higher health risk than other age groups due to fluoride, nitrate and nitrite. There is need to monitor the drinking water quality on repetitive and habitual basis. Reverse osmosis membrane filtration and adsorption technique should be adopted on domestic level to reduce the contaminations of drinking water. [ABSTRACT FROM AUTHOR]

The high concentration of fluorides, nitrates, and nitrites in water causes methemoglobinemia and gastrointestinal cancer. The purpose of this research is to investigate the physiochemical analysis and concentration of fluoride, nitrate, and nitrite with interconnected health hazards due to potable water. The potable water samples were collected from 48 different rural and urban areas of district Vehari, Pakistan. The concentration of fluoride, nitrate, and nitrite are 0.29–0.86, 0–14.086, and 0–0.005 mg/L, respectively. Nitrate at one place is reported 14.086 mg/L which is much higher than other area reports. The findings of this study indicate that concentrations of fluoride, nitrate, and nitrites are less than WHO guidelines. The chronic daily intake (mg/kg/day) and hazard quotient calculated by concentration are also in safe limits, so this region is on the safe side concerning health hazards. [ABSTRACT FROM AUTHOR]

Fluoride is used both systemically and topically to prevent and treat dental caries but has the potential to cause adverse health effects. Knowing the amount of fluoride in toothpaste is important for estimating risk. The aim of the present study was to examine the labelling of toothpastes, both fluoridated and non-fluoridated, in the market in the North West Region of Pakistan with respect to availability, country of origin, fluoride content, and recommendations for use. Twenty-four toothpastes were identified of which 6 (25%) were recommended for use in children, 3 (12.5%) were for use in both children and adults, and 15 (62.5%) did not specify which age group they were intended for. One toothpaste was labelled with the statement that children below age of seven should use a very small portion of the toothpaste. Almost half of the toothpastes are portrayed as being a remedy for tooth and gum related problems such as tooth decay, tooth sensitivity, tooth whitening, and stain removal including stains due to smoking. Sixteen (66.6%) toothpastes were imported and eight (33.3%) were made in Pakistan. Seventeen (71%) of the toothpastes contained fluoride (sodium monofluorophosphate: 9, sodium fluoride: 5, stannous fluoride: 2, and unspecified: 1). The fluoride concentration was given as a percentage in 10, as mg/g in 1, and not given in 6. It was observed that the toothpastes did not have uniformity or complete information in their labelling and that the responsible authorities should take action to ensure proper labelling. [ABSTRACT FROM AUTHOR]

This study investigated the levels of fluoride (F) and nitrate (NO 3) and their associated potential health implications via the consumption of drinking water from different sources across various provinces of Pakistan. A dataset comprising mean values of F and NO 3 based over the past 20 years (2002−2022) published were collected from Willey, ResearchGate, Springer, Mendeley, Science Direct, Google Scholar, etc. The data was plotted on their locations using spatial distribution maps, which showed high variations in concentrations of F and NO 3. Results revealed that the highest F contents were noted in the Sindh province and NO 3 levels in the Punjab province. These results indicated that excessive and inadequate F concentrations pose potential health risks. Similarly, elevated NO 3 levels in Punjab and Sindh provinces could pose health hazards like blue-baby syndrome and various other diseases. The nitrate pollution index (NPI) revealed diverse patterns, signifying distinct pollution sources across Pakistan. According to NPI results, the Baluchistan and Punjab provinces exhibited very high NO 3 pollution (NPI > 3) compared to others. The non-carcinogenic hazard quotient (HQ) for F and NO 3 was higher than 1 for children in the Sindh and Punjab provinces, respectively. In contrast, the lowest of 0.1 was noted for adults in the Gilgit-Baltistan province due to F intake. The results revealed that children were considered more vulnerable to F and NO 3 than adults in the country. The current study recommended the proper mitigation strategies for each province, especially in the Punjab and Sindh provinces, emphasizing the need for interdisciplinary studies to bridge knowledge gaps and ensure sustainable water management practices. [Display omitted] • Fluoride and nitrate data for years 2002–2022 were compared at provincial level. • Results revealed that highest fluoride contents and associated risk in Sindh province • Results revealed that the highest nitrate levels and associated risk in Punjab province • Nitrate showed higher risk than fluoride via drinking water consumption in Pakistan. • This study identified knowledge gaps that ensure sustainable water management. [ABSTRACT FROM AUTHOR]

Groundwater of the Thar Desert in Sindh province of Pakistan is known to have high fluoride concentration whose use for drinking purpose has led to a catastrophic prevalence of dental and skeletal fluorosis. Therefore, as a remedial measure to this problem, with an aim to bring fluoride levels in drinking water below the WHO limit of 1.5 mg/L, adsorption experiments have been carried out in this study in the batch and column modes and extended to the pilot scale investigations using alumina as the adsorbent. The batch mode experiments helped optimize the adsorption parameters such as adsorption time, adsorbent dose, and pH and the values were found to be 50 min, 2.0 g, and 6-7, respectively. Batch adsorption data further showed greater compatibility with Freundlich adsorption isotherm as well as pseudo-second-order model. The thermodynamic experiments revealed that the process is endothermic and spontaneous with Gibb's free energy ranging from -7.56 to -8.13 kJ/mol. A percentage removal of almost 95% in the batch mode was encouraging to carry the study to the column mode which represents a more pragmatic approach. Column experiments were carried out in a column of 33 cm length and 3.4 cm of the internal diameter which resulted in the breakthrough adsorption capacity of 4.98 mg/g at an initial fluoride concentration of 10 mg/L. Thomas and Yoon-Nelson adsorption models fitted well with the data with high values of determination coefficients. The maximum adsorption capacity Qm and the rate constant KTH obtained via Thomas model were found to be 8.82 mg/g and 0.0012 L/min mg, respectively, and the values of KYN and τ from Yoon-Nelson model were found to be 0.0128 min-1 and 426.83 min, respectively. The column containing 5.0 g of alumina reached exhaustion after passing 7.1 L of 10.3 mg/L fluoride solution. It was subsequently regenerated with 1% NaOH with a desorption efficiency of 92%. Based on these results, a pilot plant was designed that contained 60 kg bed of alumina in a vessel of 13 inch internal diameter and 60 inch height. Experiments with pilot plant revealed that the plant can serve around 20,000 L of fluoride-safe drinking water if the initial fluoride concentration of the water is approximately 10 mg/L. The plant was successfully used up to the third cycle with decreasing efficiency of fluoride removal. These results are highly encouraging and pragmatic which will be helpful in engineering a real-time plant for the people of Thar desert to provide them with a fluoride-safe drinking water and overcome the menace of the fluorosis completely from the area. [ABSTRACT FROM AUTHOR]

Current studies were performed to evaluate the physico-chemical characteristics and therapeutic potential of Chutrun thermal springs located in the North-west of Shigar Valley, Gilgit-Baltistan (Pakistan). Thermal springs with different mineral contents have been used by people for bathing and health purposes since old timings. The mineral water of these springs contains elements like sodium, potassium, calcium, magnesium as chlorides, fluorides, sulphates, phosphates and bicarbonates which may be responsible for cure of various diseases. Chutrun hot springs have 7.21–7.8 pH, 40–42° C Temperature, 300–310 ppm TDS, 3.1–6.7 ppm DO, 278–285 ppm hardness, 1.62–2.42 ppm turbidity, 250–260 ppm alkalinity, 500–516 ppm conductivity, 12–18 ppm sodium, 3.8–4.1 ppm potassium, 80–82 ppm calcium, 20 ppm magnesium, 9.6–12 ppm chlorides, 3.4–3.9 fluorides, 260–282 bicarbonates and 80–85 ppm sulphates. Absence of E.Coli and faecal coliforms indicated that waters from thermal springs are free from organic wastes contaminations. Water from thermal springs of Chutrun was unsuitable for drinking purposes due to the presence of high fluoride content and also small amount of total coliforms which may be due to the presence of environmental bacteria and non-protective measures during sampling but it was found suitable for bathing and other body contact activities. [ABSTRACT FROM AUTHOR]

Removal of fluorides from water is essential for humans and animals because it causes dental and bone deficiency. The maximum permissible limit of fluoride is 1.5 mg/L, according to the World Health Organization. Recently it became known that countries like Pakistan, India, Sri Lanka, China, Argentina, etc. have high fluoride concentration in groundwater. In the present work, calcium peroxide nanoparticles adsorption behaviour and its fluoride removal efficiency from an aqueous phase was studied. Adsorption technique was used to concentrate fluoride on the adsorbent. The advantage of using adsorption is that it is a technique which is easy to implement and relatively cheap. To characterise the structure, size and morphology of adsorbent nanoparticles, Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy with energy dispersion X-ray spectroscopy, and Raman spectroscopy were applied. In batch adsorption experiments, the process parameters varied were: pH (2–12); contact time (5–60 min); adsorbent dosage (0.05–1 g); concentration (10–100 mg/L), and temperature (5–60°C). The kinetic study has shown that the experimental data are consistent with pseudo second order model with the regression coefficient of 0.99. The adsorption equilibrium is best describable by Langmuir isotherm model with adsorption capacity of 89.6 mg/g. The process thermodynamic was also studied to confirm the proposed mechanism of fluoride adsorption on the adsorbent. The isothermal multistage adsorption was investigated to understand the mechanism of calcium peroxide nanoparticle adsorption for fluoride removal. The maximum fluoride adsorption capacity calculated for CaO2 was 89 mg/g, with 90% defluoridation efficiency. The results suggested that calcium peroxide nanoparticles can be considered as a promising adsorbent for fluoride removal. [ABSTRACT FROM AUTHOR]

Fluoride is present naturally in the environment and may reach levels that impair the bio-physiological processes in plants. The aim of the present study was to examine the effect of sodium fluoride (NaF) stress on the yield of Solanum melongena L., (aubergine, brinjal, eggplant), a member of the Solanaceae family with edible properties. In a pot experiment, lasting from August to October 2017, NaF was applied twice weekly as a soil drench and a foliar spray in concentrations of 100, 200, 300, 400, 500, and 600 ppm. The yield of S. melongena was severely affected by the NaF in a doserelated manner with the maximum yield reduction observed at 600 ppm NaF. The soil drench affected the plants more than the foliar spray application. The results showed that S. melongena is a salt sensitive crop. [ABSTRACT FROM AUTHOR]

The interaction between plants and fluoride occurs due to the contamination by fluoride of air, soil, and ground water. Fluoride pollution is worldwide and may cause serious damage to plants and consequently affect both livestock and human beings. Air pollution by fluoride is widespread in Pakistan and affects crop production. The aim of the present study was to examine the impact in maize (Zea mays L.) of 15 days treatment with sodium fluoride (NaF), in concentrations of 0 (control), 10, 20, and 50 mg/L, on germination percentage, root and shoot length, vigor index, total chlorophyll content, and total protein content. The group size was 50 seeds for each analysis. Increasing concentrations of NaF resulted in reductions in the germination percentage, root and shoot length, vigor index, and total protein content. Our finding that the total chlorophyll content increased with a peak at 20 mg/L NaF and a value at 50 mg/L still above the control value was anomalous compared to the literature. It was concluded that fluoride had a negative effect on the crop productivity of Zea mays L. and that soil contamination by fluoride should be prevented. [ABSTRACT FROM AUTHOR]

Fluoride is a naturally accruing element which harms our environment. Accumulation of excess fluoride in the environment poses a serious threat to plants. It causes various changes in the biophysiological processes of plants. The present study was conducted to determine the effect of NaF on Solanum melongena L. (brinjal, bengun, aubergine, eggplant). S. melongena belongs to the family Solanaceae and is an important edible plant. It was grown during the crop season (August-October, 2017) in pots. Different concentrations of NaF, i.e., 100, 200, 300, 400, 500, and 600 ppm, were applied, along with a control, as a soil drench and foliar spray twice a week. The parameters examined to determine the effect of the stress of NaF on the plant growth were the shoot and root length and the number and the area of the leaves. There was a dose-related reduction in growth with the NaF treatment. In general, the soil drench affected growth more than the foliar spray. The results show that Solanum melongena L. is a salt sensitive crop. [ABSTRACT FROM AUTHOR]

Hydrogeochemical methods were integrated to delineate the geochemical factors controlling fluoride (F-) contamination in groundwater at four sites in the districts of Lahore (Samada) and Kasur (Sari Chimba, Kot Maiga, and Chah Fatehwala) in Panjab province of Pakistan. Hydrochemical data and stoichiometric ratios indicate Na–Cl and Na–HCO3 as the dominant water types with silicate weathering influencing overall hydrogeochemistry of the study area. The groundwater F- concentrations ranged between 0.54 mg/L and 17.5 mg/L, with more than 70% samples having F- concentrations above the World Health Organization (WHO) provisional drinking water guideline (1.5 mg/L). Saturation indices determined that 100% samples were saturated with respect to calcite and 96% samples were undersaturated with respect to fluorite, indicating the influence of calcite precipitation on fluoride enrichment. A positive correlation was observed between fluoride with pH, Na+, and HCO3−, confirming that high fluoride concentrations were the result of weathering of silicate minerals and the exchange of OH- on clay surface under the alkaline pH conditions. The isotopic values of δ18O and δ2H in groundwater ranged from 9.14 to − 5.51‰ and 56.57 to − 39.5‰, respectively. The stable isotope data indicated the meteoric origin of groundwater with some evaporative effect, which is partly influencing groundwater quality such as high pH and salinity, as a result facilitating anion exchange (OH- for F-) on clays surface. The research indicates that the groundwater quality of the study area is not recommendable for drinking due to its high total dissolved solids (TDS) and elevated fluoride concentrations. [ABSTRACT FROM AUTHOR]

A cross-sectional study was undertaken to determine the level of urinary fluoride and dental fluorosis in brick kiln workers (n=100) and a control group (n=20) in Balochistan, Pakistan. The fluoride level was also assessed in groundwater samples (n=30). The results showed the urinary fluoride level was significantly greater (p<0.05) in the brick kiln workers (0.17-0.30 mg/L) than in the control individuals (0.003 mg/L). Dental fluorosis was prevalent in both the brick kiln workers and the control group and the Community Fluoride Index (CFI) values were less than 0.42. The range of the groundwater fluoride levels was 0.87 to 1.59 mg/L with the upper part of the range being above upper limit recommended by the WHO (1.5 mg/L). Significant positive correlations (r=0.98, 0.90, 0.96) were determined between groundwater fluoride, urinary fluoride, and dental fluorosis. Consequently, it is assumed that the level of urinary fluoride and dental fluorosis could increase due to fluoride emissions from brick kilns and groundwater fluoride. The results of the current study suggest urinary fluoride and dental fluorosis are effective biomarkers for the monitoring of short-term and prolonged exposure to fluoride, although dental fluorosis is an indicator of fluoride exposure only while the teeth are developing up until the age of approximately 8 years. In order to avoid the long-term health-related consequences of fluoride exposure, regular monitoring of fluoride levels in the vicinity of brick kilns is recommended. [ABSTRACT FROM AUTHOR]

In this study, an examination was made of the size, fresh weight, and dry weight of turnip, Brassica rapa L., at 70 days after sowing (DAS) when different concentrations of sodium fluoride (NaF) (0 [control], 50 [NaF-50], 100, 150, 200, and 300 [NaF-300] ppm) were applied. The size of the turnip was maximal in the control plants, 20.82 cm2. In the plants given NaF-50, as both a soil drench and as a foliar spray, the sizes were 16.32 cm2 and 18.08 cm2, respectively. The size of the turnip gradually decreased as the NaF stress was increased and was at a minimum with NaF-300 for both methods of application (soil drench: 2.47 cm², foliar spray 4.35 cm²). At 70 DAS, the fresh weight was greatest, 66.60 g, in the control plants, followed by 43.06 g, in the plants given NaF-50 by foliar spray. The fresh weight successively declined as the concentration of NaF increased and at NaF-300 and it reached a minimum for both the soil drench, 1.36 g, and the foliar spray, 2.43 g. The dry weight was recorded by oven drying the fresh turnip at 70 DAS, and found to be at a maximum in the control plants, 6.60 g. When a fluoride stress was applied with NaF-50, as a soil drench and a foliar spray, the dry weight decreased to 4.30 g and 5.06 g, respectively. As the concentration of NaF increased, the dry weights decreased in a manner similar to that found with the fresh weights and the lowest values were found with NaF-300 (soil drench: 0.556 g, foliar spray: 1.20 g). In conclusion, NaF applied as both a soil drench and a foliar spray, at concentrations of 50-300 ppm, reduced the size, fresh weight, and dry weight of turnip compared to a control group with 0 ppm NaF. The application of the NaF by soil drench caused a greater degree of stress to the turnip than did the application by foliar spray. [ABSTRACT FROM AUTHOR]

The production of bricks by baking in kilns has occurred since ancient times in South Asia. The growth of modern urbanization has resulted in more kilns being required for brick production. Kilns are a source of fluoride emissions which cause damage to plants growing nearby. The aim of the present study was to study the effect of fluoride emissions from brick kilns on winter wheat being cultivated in the surrounding fields. The study (i) assessed the damage caused by fluoride to the wheat plants, (ii) determined the concentration levels of fluoride in the leaves, and (iii) measured the plant health index. The fluoride concentration was measured with a fluoride ion meter and the plant health was assessed using a raster calculator in ArcGIS 10.2v. The results revealed that great damage occurred, with visible foliar injury, to the wheat plants located within 100 m of the brick kilns. [ABSTRACT FROM AUTHOR]

The influence of sodium fluoride on two cultivars of okra (Nirali and Arka Anamika) was evaluated during the seedling and growth stages, by applying different concentrations of NaF (50, 100, 150, 200, 250, and 300 ppm). All the parameters studied showed a greater reduction with the higher concentrations of sodium fluoride (250 and 300 ppm) than with the lower concentrations (50 and 100 ppm). In cultivar Nirali, the plants treated with 300 ppm NaF showed reduction percentages in the shoot and root fresh weight, of 84% and 90%, respectively, while the corresponding reductions in Arka Anamika were 82% and 91%. Increased concentrations of fluoride can significantly decrease plant pigment levels (chlorophyll a & b, total chlorophyll, and total carotenoids), the total soluble sugar, and the protein content. In contrast, increasing concentrations of sodium fluoride, increased the proline content significantly. [ABSTRACT FROM AUTHOR]

The present study aims to investigate the spatial distribution and associated various geochemical mechanisms responsible for fluoride (F⁻) contamination in groundwater of unconfined aquifer system along major rivers in Sindh and Punjab, Pakistan. The concentration of F⁻ in groundwater samples ranged from 0.1 to 3.9 mg/L (mean = 1.0 mg/L) in Sindh and 0.1–10.3 mg/L (mean = 1.0 mg/L) in Punjab, respectively with 28.9% and 26.6% of samples exhibited F⁻ contamination beyond WHO permissible limit value (1.5 mg/L). The geochemical processes regulated F⁻ concentration in unconfined aquifer mainly in Sindh and Punjab were categorized as follows: 1) minerals weathering that observed as the key process to control groundwater chemistry in the study areas, 2) the strong correlation between F⁻ and alkaline pH, which provided favorable environmental conditions to promote F⁻ leaching through desperation or by ion exchange process, 3) the 72.6% of samples from Sindh and Punjab were dominated by Na⁺- Cl⁻ type of water, confirmed that the halite dissolution process was the major contributor for F⁻ enrichment in groundwater, 4) dolomite dissolution was main process frequently observed in Sindh, compared with Punjab, 5) the arid climatic conditions promote evaporation process or dissolution of evaporites or both were contributing to the formation of saline groundwater in the study area, 6) the positive correlation observed between elevated F⁻ and fluorite also suggested that the fluorite dissolution also played significant role for leaching of F⁻ in groundwater from sediments, and 7) calcite controlled Ca2⁺ level and enhanced the dissolution of F-bearing minerals and drive F⁻ concentration in groundwater. In a nut shell, this study revealed the worst scenarios of F⁻ contamination via various possible geochemical mechanisms in groundwater along major rivers in Sindh and Punjab, Pakistan, which need immediate attention of regulatory authorities to avoid future hazardous implications. Image 1 • Elevated F⁻ concentrations were reported in groundwater samples from major riverine systems in Sindh and Punjab, Pakistan. • Geochemical processes regulated F⁻ concentration in unconfined aquifer of Sindh and Punjab, Pakistan. • Alkaline environmental conditions to promote F⁻ leaching through desperation/ion exchange process. • Halite dissolution process is the major contributor for F⁻ enrichment in groundwater. • Calcite controlled Ca2⁺ level and enhanced the dissolution of F-bearing minerals drive F⁻ concentration in groundwater. [ABSTRACT FROM AUTHOR]

Fluoride (F-), and arsenic (As) in the groundwater cause health problems in developing countries, including Pakistan. We evaluated the occurrence, distribution, sources apportionment, and health hazards of F-, and As in the groundwater of Mardan, Pakistan. Therefore, groundwater samples (n = 130) were collected and then analyzed for F-, and As by ion-chromatography (IC) and Inductively-coupled plasma mass-spectrometry (ICP-MS). The F-, and As concentrations in groundwater were 0.7–14.4 mg/L and 0.5–11.2 µg/L. Relatively elevated F-, and As coexists with higher pH, Na+, HCO 3 -, SO 4 −2, and depleted Ca+2 due to fluoride, sulfide-bearing minerals, and anthropogenic inputs. Both F-, and/or As are transported in subsurface water through adsorption and desorption processes. Groundwater samples 45%, and 14.2% exceeded the WHO guidelines of 1.5 mg/L and 10 µg/L. Water quality indexing (WQI-model) declared that 35.7% samples are unfit for household purposes. Saturation and undersaturation of minerals showed precipitation and mineral dissolution. Groundwater contamination by PCA-MLR and PMF-model interpreted five factors. The fitting results and R2 values of PMF (0.52–0.99)>PCA-MLR (0.50–0.95) showed high accuracy of PMF-model. Human health risk assessment (HHRA-model) revealed high non-carcinogenic and carcinogenic risk for children than adults. The percentile recovery of F- and As was recorded 98%, and 95% with reproducibility ± 5% error. [Display omitted] • Groundwater of Mardan, Pakistan was analyzed for F-, and As concentrations. • 45% and 14.2% of samples exceeded the WHO limit of F- 1.5 mg/L, and As 10 µg/L. • 10% of groundwater samples favor F- and As cooccurrence due to alkaline conditions. • Groundwater apportionment was better explained by the PMF model than PCAMLR. • Dental and skeletal fluorosis in Mardan Pakistan is evident in the local resident. [ABSTRACT FROM AUTHOR]

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 (24–40 m), mid-depth (48–65 m) and deep (85–120 m) aquifers, and then analysed using an ion-selective electrode. The lowest F − concentration (0.7 mg/L) was recorded in the deep-aquifer groundwater, while the highest (6.4 mg/L) was recorded in shallow groundwater. Most groundwater samples (62.2%) exceeded the guideline (1.5 mg/L) set by the World Health Organization (WHO); while for individual sources, 73% of shallow-groundwater samples (F − concentration up to 6.4 mg/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 3 − the major anion. The anionic and cationic concentrations across the entire study area increased in the following order: HCO 3 > SO 4 > Cl > NO 3 > F > PO 4 and Na > Ca > Mg > K, respectively. Relatively higher F − toxicity levels were associated with the NaHCO 3 water type, and the chemical facies were found to change from the CaHCO 3 to (Na HCO 3 ) 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. [ABSTRACT FROM AUTHOR]

Efficacy of fluoride as a cariostatic agent is a well-established fact. Last few decades have seen a dramatic decline in dental decay throughout the world. As a systematic approach, fluoride is added to the drinking water to prevent dental decay but topical application using toothpaste has been more effective against dental caries, therefore fluoride is added to toothpaste in the form of sodium fluoride and sodium monofluorophosphate. Based on the fact that excessive exposure to fluoride causes dental fluorosis and lower amount makes toothpaste ineffective against dental caries, so the amount of fluoride in the toothpaste must be regulated. Therefore, in the present study, toothpastes including local and imported brands sold in Karachi have been collected and analyzed for their fluoride contents. In a total of 55 samples, amount of fluoride ranged from 10 to 1,674 ppm in local samples and in imported brands it ranged from 426 to 1,444 ppm. Eighty-two percent of the local brands fell short of 1,000 ppm fluoride which is the lower limit of fluoride in toothpaste as recommended by WHO. A large amount of variations has been observed in acclaimed fluoride levels and analyzed fluoride level; furthermore, 70% of the local samples have not even mentioned the content of fluoride in their brands. In the context of increasing number of cases of dental decay in Karachi, these results provide baseline data to the authorities concerned to regulate the fluoride levels in toothpaste. [ABSTRACT FROM AUTHOR]

Drinking fluoride (F−)-contaminated water (>1.5 mg L−1) causes severe dental and skeletal disorders. In the central province of Pakistan, ∼20 times higher levels of F− in the drinking groundwater (compared with the 1.5 mg L−1 permissible limit of the World Health Organization) are triggering bone abnormalities in teenagers. In this study, we demonstrated the potential of pinecone-derived biochar (pristine) impregnated with Fe- and Al-salts (engineered) to defluoridate water. Batch mode adsorption experiments were carried out under variable conditions of solution pH, F− initial concentration, adsorbent dose, and contact time. The engineered biochars resulted in greater adsorption than that of pristine biochar. Specifically, the AlCl 3 -modified biochar exhibited a maximum adsorption capacity of 14.07 mg g−1 in spiked water and 13.07 mg g−1 in in-situ groundwater. The equilibrium isothermal and kinetic models predicted monolayer, cooperative, and chemisorption types of the adsorption process. The chemical interaction and outer-sphere complexation of F− with Al, Na, and H elements were further confirmed by the post-adsorption analysis of the AlCl 3 -modified biochar by FTIR and XRD. The AlCl 3 -modified biochar resulted in 87.13% removal of F− from the in-situ F−-contaminated groundwater, even in the presence of naturally occurring competing ions (such as Cl−, HCO 3 −, SO 4 2−, and NO 3 −). We conclude that the AlCl 3 -modified biochar derived from pinecone could be a promising cost-effective adsorbent for the defluoridation of water. • The AlCl 3 -modified biochar exhibited great potential of water defluoridation. • The biochar also showed reasonable regeneration potential. • The biochar was equally effective to the in-situ F−-contaminated groundwater. • It performed with same efficiency even in the presence of competing ions. [ABSTRACT FROM AUTHOR]

Groundwater samples (n = 152) were collected in the Thar Desert of the Umarkot Sub-District, Pakistan to evaluate the geochemical controls on the occurrence of high fluoride (F − ) levels within the study area. Fluoride concentrations range from 0.06 to 44.4 mg/L, with mean and median values of 5.22 and 4.09 mg/L, respectively; and roughly 84% of the samples contain fluoride concentrations that exceed the 1.5 mg/L drinking water standard set by WHO. The overall groundwater quality reflects the influences of silicate mineral weathering and evaporation. Fluoride originates from the weathering of minerals derived from Type-A granite and possibly anion exchange (OH − for F − ) on clays and weathered micas under high pH conditions. High fluoride levels are associated with Na–HCO 3 type water produced by calcite precipitation and/or base ion exchange. Depleted calcium levels in groundwater allow higher fluoride concentrations to occur before the solubility limit for fluorite is reached. [ABSTRACT FROM AUTHOR]

In the current study, the chemistry of fresh and stored rainwater of Thar Desert, Pakistan, was estimated during two consecutive monsoon periods. The present research deals with the variation in physicochemical parameters, total arsenic (As), inorganic arsenic species (As, As, As), and fluoride (F) in stored rainwater (SRW) at different time intervals (1 week to 3 months). The pH of fresh rainwater (FRW) samples showed slightly acidic to neutral in nature (6.08-7.06) which were inconsistent with the reference pH value (5.6) of rainwater. The resulted data indicated that As and F levels in SRW were enhanced with time duration. The levels of As and F in SRW after different time intervals were found in the range of 194-683 μg/L and 10-35.4 mg/L, respectively. The values of As and F were 20-70 and 7-24 times higher than those of WHO permissible limits, 10 μg/L and 1.5 mg/L, respectively. The As was dominant species in SRW, which corresponds to >60 % of As. The characteristics of the SRW revealed an unacceptable quality to consume for drinking and agricultural purposes in the studied area. [ABSTRACT FROM AUTHOR]

Increased urbanisation throughout South Asia has increased the number and output of the brick kilns that typically surround major cities, but the environmental and health impacts of their atmospheric emissions are poorly understood in Pakistan. We report the negative effects of hydrogen fluoride (HF) emissions from brick kilns near Peshawar, Pakistan on mung bean (Vigna radiata cv. MN 92) and maize (Zea mays cv. Azam). HF air concentrations, and fluoride concentrations of mung bean and maize grains, were greater close to brick kilns than at more distant sites. The 100-grain weight of mung bean and maize close to brick kilns was significantly lower, by about 30% and 45% respectively, than at control sites. These findings, added to evidence of major impacts on local fruit orchards in this area, suggest that fluoride emissions from brick kilns may have a significant impact on peri-urban agriculture in South Asia. [ABSTRACT FROM AUTHOR]

Abstract: Factors regulating the occurrence of high fluoride (F−) concentrations in groundwater near Nagar Parkar Town, SE corner of Pakistan have been investigated considering lithological influences. F− ion concentrations in groundwater range up to 7.85 with mean value of 3.33mgL−1. Plots of major elements and their normative mineral composition reflect granitic composition of the rocks in the study area. Modal mineralogical analysis show high perthite, plagioclase feldspars and quartz, while micas, amphiboles and pyroxenes occur in minor quantities. Water–rock interactions, based on dissolved ions of F−, SiO2, Na+, K+, Mg2+, Li+ and Sr2+ suggest that fluoriferous groundwater originates from granitic rocks, typically from albite, biotite, hornblende and pyroxene and its alteration products such as kaolin and soil. The Log TDS, Na/Na+Ca ratio, Mg/Ca+Mg and Cl/Σ anions are significant to review the impact of weathering processes which promote the availability of F− ions in the groundwater of study area. Principal component analysis (PCA) also renders close association among F− ions and other elements in the rocks and groundwater. Studies on F− estimation in the granite rock, china clay, soil and sand samples also indicate the presence of high F− concentration in these materials and average values have been found to be 1939, 710, 254 and 16mgkg−1, respectively. [Copyright &y& Elsevier]

Abstract: Fluoride in drinking water above permissible level is responsible for human being affected by skeletal fluorosis. In this study, Amberlite XAD-4™ has been modified by introducing amino group onto the aromatic ring for its application in fluoride remediation. Characterization of the modified resin was made by, FT-IR and elemental analysis (CHNS) techniques. The pH 9 was optimum value for quantitative sorption of fluoride in both batch and column experiments. The desorption of fluoride was achieved by using 10% HCl. The batch and column sorption studies of fluoride with modified resin were carried out to evaluate sorption isotherms too. Thus equation isotherms such as Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) were successfully used to model the experimental data. The sorption capacity of modified Amberlite XAD-4 resin was found as 5.04×10−3 molg−1. From the D–R isotherm parameters, it has been evaluated that the uptake of fluoride by modified resin occurs through ion exchange adsorption mechanism. The study will contribute toward the removal of fluoride from the aqueous environment as well as in the field of analytical and environmental chemistry. [Copyright &y& Elsevier]

Abstract: Fluoride concentrations in groundwater near Nagar Parkar in the Thar Desert of southeastern Pakistan range from 1.13 to 7.85mg/l, and roughly 78% of the samples contain fluoride in concentrations that exceed the drinking water standard of 1.5mg/l set by WHO. The groundwater is alkaline (pH 7.1–8.4), brackish (TDS 449–15,933mg/l), and classified as Na–Cl type water. This prevailing chemical character reflects the influence of saltwater intrusion, high evaporation rates, and ion exchange. Groundwater is also supersaturated with respect to calcite, which promotes the removal of Ca2+ and HCO3 − from solution. As a result, groundwater is generally undersaturated with respect to fluorite, the mineral that typically controls the upper limit of fluoride concentrations. This study examines a number of geochemical parameters in an effort to discover the controls on fluoride concentrations in groundwater. High fluoride concentrations are associated with high TDS, high pH, high Na concentrations, and high sodium absorption ratios (SAR). This suggests that elevated fluoride levels are the result of enhanced fluorite solubility due to Ca depletion and high ionic strength and the release of fluoride from colloid surfaces under high pH conditions. Contrary to what has been found in other studies, sample depth and water temperature do not appear to have a significant role in the distribution of fluoride within the groundwater. [Copyright &y& Elsevier]

Groundwater samples were collected from various localities of Mithi sub-district of the Thar Desert of Pakistan and analysed for fluoride ion along with other chemical parameters. The area is mainly covered by sand dunes and kaolin/granite at variable depths. Results showed that collected water samples were severely contaminated by the presence of fluoride ion and most of the samples have higher concentration than prescribed WHO standards (1.5 mg/l) for drinking water. Fluoride ion concentrations ranged between 0.09 and 11.63 mg/l with mean and median values of 3.64 and 3.44 mg/l, respectively, in this area whereas, distribution pattern showed high concentrations in the vicinity of Islamkot and Mithi towns. The content of F− has also been correlated with other major ions found in the groundwater of the study area. The positive correlation of F− with Na+ and HCO3 − showed that the water with high Na+ and HCO3 − stabilizes F− ions in the groundwater of the Thar Desert. The pH versus F− plots signifies high fluoride concentration at higher pH values, implying that alkaline environment favours the replacement of exchangeable OH− with F− in the groundwater of Mithi area. The saturation indices (SI) of fluorite (CaF2) and calcite (CaCO3) in the groundwater samples showed that most of the samples are oversaturated with respect to calcite whereas majority of samples have been found under saturated with respect to fluorite. The log TDS and Na/Na+Ca ratio reflected supremacy of weathering of rocks, which promotes the availability of fluoride ions in the groundwater. Piper diagram has been used to classify the hydrofacies. In the cation triangle, all samples are Na-type, while the anion triangle reflects major dominance of Cl-type with a minor influence of HCO3 − and SO4 −. [ABSTRACT FROM AUTHOR]

The ground and municipal water supply samples of Karachi city were analyzed for their fluoride contents. The fluoride contents in water samples collected from the subsurface and river sources were found below the WHO recommended value for the general health of the people. However, in some industrial areas the groundwater sample showed higher level of fluoride concentration. Continuous monitoring of water resources and cautious fluoridation is suggested to maintain proper status of fluoride concentration in the drinking water. [ABSTRACT FROM AUTHOR]

The drinking water of Naranji village and surrounding areas of the NorthWest Frontier Province (NWFP), Pakistan, was analyzed for its fluoride content. The fluoride content of water samples from the springs in the Naranji village goes up to 13.52 mg kg-1, which exceeds the permissible limit (1.5 mg kg-1) set by the World Health Organization (WHO). This study explores the source of fluoride contamination and attributes it to the alkaline rocks of the Ambela granitic complex and the Koga complex. The low-lying areas towards the south have a fluoride content within the permissible limit. The Naranji area therefore needs urgent remedial measures. [ABSTRACT FROM AUTHOR]

The present study aimed at exploring the sources of salinity and the link it shares with the enrichment of As (arsenic) and F- (fluoride) in the groundwater of Rachna Doab. Total Dissolved Solids (TDS) were used as the measure of salinity to classify samples into three groups: TDS <1000 mg/L (freshwater), 1000–3000 mg/L (slightly saline) and 3000–10,000 mg/L (moderately saline). The stable isotope analysis (δ2H and δ18O relative to VSMOW) were used to explore the sources of salinity and a conceptual model, based on secondary data was used for comparing the current and past scenarios of groundwater salinization sources. Groundwater ion chemistry and geochemical modeling (PHREEQC) were used to develop a link between the occurrence of salinity and enrichment patterns of As and F- in the groundwater of study area. TDS, As and F- concentrations in groundwater ranged from 234 to 4557 mg/L, below detection limit to 240 μg/L and below detection limit to 3.9 mg/L, respectively. Mineral dissolution, ion exchange processes, and partial input of evaporation were identified as the factors affecting groundwater salinity in the region in accordance with the conceptual model developed based on secondary data. Groundwater salinity accounts as one of the factors that positively influence the enrichment of F- in groundwater, whereas As shows no clear relationship with saline groundwaters. Image 1 • Salinity is due to ion exchange, mineral dissolution, and partial input of evaporation. • Arsenic showed no clear relationship with salinity in groundwater of study area. • Saline ground waters had relatively oxidizing conditions that restricted As enrichment. • Groundwater salinity is one of the factors which influences the enrichment of F−. [ABSTRACT FROM AUTHOR]

Oral diseases caused by various microorganisms are common around the world. Scientific research has now been focusing on novel medicines to overcome bacterial resistance and antibiotics side effects; therefore, the current study was designed to assess the efficacy of certain antibiotics, toothpaste, and medicinal plant extracts (Ajuga bracteosa and Curcuma longa) versus the bacterial pathogens isolated from the human oral cavity. A total of 130 samples were collected from Khyber Teaching Hospital Peshawar, Pakistan, among those 27 species isolated, and eight bacterial species were identified from the samples. Among all the bacterial species, Staphylococcus aureus (29.62%) and Proteus mirabilis (22.2%) were found to be more prevalent oral pathogens. In comparison, the least pervasive microbes were Proteus vulgaris, Shigella sonnei, Escherichia coli and Aeromonas hydrophila. The study also suggested that dental problems were more prevalent in males (41-50 years of age) than females. Among the eight antibiotics used in the study, the most promising results were shown by Foxicillin against A. hydrophila. The survey of TP1 revealed that it showed more potent antagonist activity against Proteus vulgaris as compared TP2 and TP3 that might be due to the high content of fluoride. The Curcuma longa showed more significant activity than Ajuga bracteosa (Stem, leaves and root) extracts. The data obtained through this study revealed that antibiotics were more effective for oral bacterial pathogens than toothpaste and plant extracts which showed moderate and low activity, respectively. Therefore, it is suggested that the active compounds in individual medicinal plants like Curcuma longa and Ajuga bracteosa could replace the antibiotics when used in daily routine as tooth cleansers or mouth rinses.

The present study examined the hydrogeochemical profile of higher fluoride (F─) in groundwater of mixed industrial and mining areas of Dargai, northern Pakistan. Groundwater samples (n = 75) were collected from three hydrogeochemical environments. The mean concentrations of pH, EC, TDS, Depth and Temperature were (7.6, 1081 μS/cm, 590 mg/L, 75 m, 28.03 °C), for chemical ions viz. NO 3 , PO 4 , SO 4 , Cl, HCO 3 , Na, K, Ca and Mg were (18.5, 2.7, 161, 107, 330, 150, 9.76, 33, 52) mg/L respectively. Whereas, the mean concentration of F─ was 2.0 mg/L. Therefore, 51% groundwater samples exceeded the WHO guideline of F─ 1.5 mg/L. Additionally, we measured the mean F─ concentration in rocks, coal and wastewater, which were (670, 98) mg/Kg and 2.3 mg/L respectively. The principal component analysis multilinear regression (PCA─MLR) extracted five significant factors which shows natural, mixed and anthropogenic pollution. Thus, fluorite is the primary source of F─ contamination in groundwater. While apatite, biotite and muscovite minerals are the secondary sources which occurs in association with quartzite, granite rocks. Under alkaline conditions, F─ contamination is supported by higher Na+, HCO 3 ─ and lower Ca++ concentrations. The accuracy and reproducibility of the measurement of fluoride was assessed by adopting a standard method of water. The percentage recovery of F─ was 97% and reproducibility was within ±5% error limit. Lastly, a health risk community fluorosis index (CFI) was calculated through Dean's formula which shows unsuitability of groundwater sources conceiving community fluorosis in the entire study area. • Groundwater of Dargai region, Pakistan was analyzed for fluoride concentrations. • 51% of groundwater samples exceeded the WHO guideline value of 1.5 mg/L of F─. • F─ occurrence in water is linked to ion exchange, weathering and mining actions. • PCA-MLR results of groundwater shows 64% contamination was due to geogenic source. • CaHCO 3 (49%), NaHCO 3 and NaCl (51%) are the major water type of the study area. [ABSTRACT FROM AUTHOR]

In low concentration, fluoride is considered a necessary compound for human health. Exposure to high concentrations of fluoride is the reason for a serious disease called fluorosis. Fluorosis is categorized as Skeletal and Dental fluorosis. Several Asian countries, such as India, face contamination of water resources with fluoride. In this study, a comprehensive overview on fluoride contamination in Asian water resources has been presented. Since water contamination with fluoride in India is higher than other Asian countries, a separate section was dedicated to review published articles on fluoride contamination in this country. The status of health effects in Asian countries was another topic that was reviewed in this study. The effects of fluoride on human organs/systems such as urinary, renal, endocrine, gastrointestinal, cardiovascular, brain, and reproductive systems were another topic that was reviewed in this study. Different methods to remove fluoride from water such as reverse osmosis, electrocoagulation, nanofiltration, adsorption, ion-exchange and precipitation/coagulation were introduced in this study. Although several studies have been carried out on contamination of water resources with fluoride, the situation of water contamination with fluoride and newly developed technology to remove fluoride from water in Asian countries has not been reviewed. Therefore, this review is focused on these issues: 1) The status of fluoride contamination in Asian countries, 2) health effects of fluoride contamination in drinking water in Asia, and 3) the existing current technologies for defluoridation in Asia. Image 1 • The status of fluoride contamination in groundwater of Asian countries is reviewed. • India, Pakistan and China are critically affected by fluoride contamination. • Dental fluorosis is major adverse effect due to fluoride contamination in water. • Various defluoridation techniques have been discussed. • More research on fluoride decontamination is suggested. [ABSTRACT FROM AUTHOR]

Consumption of groundwater with elevated levels of the fluoride ion (F-) for drinking purpose is a major F- exposure pathway for humans. Groundwater samples (n=100) were collected from 25 villages of district Mardan of the Khyber Pakhtunkhwa (KP) province and analyzed for anions including F-, chloride (Cl-), bromide (Br-), phosphate (PO43-) and sulfate (SO42-) through ion chromatography. The concentrations of F- in the groundwater samples ranged between 0.05 mg/L and 10.8 mg/L. The measured concentrations were within the permissible limits of the National Environmental Quality Standards (NEQS) of Pakistan for drinking water in 92% of the samples. The groundwater samples of three villages exhibited a Fconcentration greater than the permissible level of 1.5 mg/L. F- has shown a positive correlation with electrical conductivity (EC), total dissolved solids (TDS), Br-, PO43- and SO42-. To safeguard public health this study suggests further research in the area for possible sources and mitigation measures of F- contamination. [ABSTRACT FROM AUTHOR]

The increasing consumption of soft drinks, juices, and other beverages as a replacement for water have made the fluoride content in beverages an important issue. Fluoride intake greater than a certain limit may increase the risk for and development of dental fluorosis. This study was designed to evaluate the fluoride content in some commonly used brands of industrialized beverages consumed in Rawalpindi, a highly populated city of Pakistan. All the samples were chosen on the basis of their high public demand. an ion selective electrode (ISE) was used for the determination of the fluoride contents in juice and soft drink samples. The concentration of fluoride observed in all the analyzed samples ranged between 0.002 mg/L and 0.2 mg/L. The concentration of fluoride in most of the examined beverages was below 0.1 mg/L and lay within the values provided by the USDA database on the fluoride content of particular beverages. Therefore, it was concluded that ingestion of these beverages where concentration was below 0.1 mg/L at moderate level may not increase the human exposure to fluoride. However, a few brands were identified with greater concentrations of fluoride that may affect the teeth and skeleton. [ABSTRACT FROM AUTHOR]