Fluoridation Research Articles

Assessment of Fluoride Level in Drinking Water Sources of Jumla, Nepal

Introduction: Dental caries is one of the most prevalent chronic diseases. Though, preventable recent trend shows an increase in the prevalence of dental caries in developing country like Nepal. Optimal level of Fluoride in drinking water has a proven effect of preventing dental caries. Objective: The objective of this study was to estimate the amount of fluoride in drinking water of Jumla, Nepal. Methods: This study was an observational cross-sectional study conducted from August to September 2022 during which 78 drinking water samples were collected from different randomly selected wards of one municipality and seven rural municipality of Jumla district using simple random sampling technique. The drinking water sample for fluoride level of different area was analyzed and interpreted using SPADNS colorimetric method which is set as standard by American Public Health Association. Results: A total of 78 samples were collected from distinctive drinking water sources of randomly selected wards of 7 rural municipality and a municipality. Out of 78 samples collected, only 5 samples (6.41%) had a fluoride concentration of more than 0.5mg/L. The highest fluoride concentration was 1.31mg/L. The overall mean (±SD) fluoride concentration of Jumla district was 0.20(±0.24). The median (Q1-Q3) concentration of fluoride in drinking water of Jumla district was estimated to be 0.11mg/L (0.05-0.29). Conclusions: This study estimated the fluoride level in drinking water of Jumla district to be below the optimal level and shows the importance of water fluoridation in order to prevent dental caries.

Awareness Survey on Community Water Fluoridation by Region

Awareness Survey on Community Water Fluoridation by Region

Use of calcined camel bones for water fluoridation of five boreholes in the Maradi region, Niger

Use of calcined camel bones for water fluoridation of five boreholes in the Maradi region, Niger

Use of calcined camel bones for water fluoridation of five boreholes in the Maradi region, Niger

The presence of fluorides in drinking water has become a major concern worldwide due to their chronic carcinogenic behavior for humans. The development of easily accessible and environmentally friendly disposal strategies is therefore a challenge for scientists. Camel bones calcined at different temperatures and then activated with HCl at different concentrations were used for the removal of fluorides ions from an aqueous solution. The effect of activate concentration, initial adsorbate concentration, contact time and adsorption process were studied. In addition to these previous parameters, the influence of co-existing ions on the adsorption capacity of fluorides ions was investigated. The optimal dose on calcined and activated camel bones is 16g / L with a maximum adsorption capacity of 0.63 mg / g. After optimization of this parameter an application on natural waters was realized. The study showed that the calcined and activated dromedary or camel bone is a promising adsorbent for the removal of fluorides ions from fluoridated or contaminated or drinking water.

Influences of Synthetic Parameters on Morphology and Growth of High Entropy Oxide Nanotube Arrays

Nanoscale and nanostructured materials have drawn great attention owing to their outstanding and unique properties. Enlightened by the study of “entropy-stabilized oxides”, nanotubes consisting of multi-component mixed metal oxides are developed, which formed on equi-atomic TiZrHfNbTa high-entropy alloy (HEA). However, the growth mechanism and how the oxidation conditions influence the nanotube growth and morphology remains unknown. In the present study, by controlling the anodization parameters (applied voltages and time) and bath compositions (fluoride concentration and water content), scanning electron microscope and transmission electron microscopy are conducted to reveal the morphological evolution. The present work uncovers how the synthetic parameters influence the tube growth and morphology formed on equi-atomic TiZrHfNbTa HEA, therefore gaining insight into the growth mechanism and the feasibility of controlling the morphology of multi-component oxide nanotubes.

Epidemiology of dental caries in permanent dentition: evidence from a population-based survey in Egypt

BackgroundIn recognition of the risk factors common between oral diseases and various chronic conditions and the intersection between oral health and some sustainable development goals, the current cross-sectional study was designed to quantify the burden of dental caries and identify factors associated with its occurrence in permanent teeth.MethodsUsing data from Egypt's population-based survey (2013–2014), two individual-level outcomes; past caries experience (DMFT > 0) and presence of untreated carious lesions (DT > 0) were assessed using the WHO basic methods for oral health surveys. Information on potential explanatory variables including sociodemographic characteristics, exposure to fluoridated water, dental attendance, and dental anxiety was gathered using a structured questionnaire. Stratified multistage cluster random sampling was used to recruit survey participants. Multivariable logistic regression was performed to identify significant potential risk factors for caries in the permanent dentition of Egyptians.FindingsA total of 9,457 participants were included of which 70.3% had at least one untreated carious lesion. After adjusting for all covariates, analphabetic Egyptians were found to have significantly higher odds of caries experience in permanent dentition DMFT > 0 (OR 1.54, 95% CI [1.20–1.98]), DT > 0 (OR 1.62, 95% CI [1.32–2.00]). Males, however, had significantly lower caries risk DMFT > 0 (OR 0.75, 95% CI [0.67–0.85]), DT > 0 (OR 0.81, 95% CI [0.73–0.89]) when compared to females. Regarding age, mean DMFT scores were significantly lower in age groups (6–15 years) (OR 0.03, 95% CI [0.014; 0.082]), (16– 20 years) (OR 0.09, 95% CI [0.037; 0.23]), and (21–35 years) (OR 0.22, 95% CI [0.09; 0.53]) than among people ≥ 60 years. ConclusionAddressing individual-level caries risk factors should be complemented by addressing upstream factors to reduce burden of untreated dental caries among Egyptians.

Do missing teeth cause early-onset cognitive impairment? Re-examining the evidence using a quasi-natural experiment

PurposeMultiple studies have reported a positive association between missing teeth and cognitive impairment. While some authors have postulated causal mechanisms, existing designs preclude assessing this.MethodsWe sought evidence of a causal effect of missing teeth on early-onset cognitive impairment in a natural experiment, using differential exposure to fluoridated water during critical childhood years (ages 5–20 years) in England as the instrument. We coded missing teeth from 0 (≤ 12 missing) to 3 (all missing) and measured the association with cognitive impairment in the English Longitudinal Study of Ageing data (2014–5), covering 4958 persons aged 50–70 years.ResultsWe first replicated previous evidence of the strongly positive association of missing teeth with cognitive impairment (β = 0.25 [0.11, 0.39]), after adjusting for socio-demographic covariates, such as age, gender, education, and wealth. Using an instrumental variable design, we found that childhood exposure to water fluoridation was strongly associated with fewer missing teeth, with being exposed to fluoridated water during childhood (16 years) associated with a 0.96 reduction in the missing teeth scale (β = − 0.06 [− 0.10, − 0.02]). However, when using the instrumented measure of missing teeth, predicted by probability of fluoride exposure, we found that missing teeth no longer had an association with cognitive impairment (β = 1.48 [− 1.22, 4.17]), suggesting that previous oral health-cognitive impairment associations had unobserved confounding.ConclusionsOur findings are consistent with the possibility that unobserved confounding leads to the oft-observed association between missing teeth and early-onset cognitive impairment, suggesting that the relationship is spurious rather than causal.

Vitamin D deficiency in patients with diabetes and its correlation with water fluoride levels.

Chronic exposure to fluoride through drinking water has been linked to insulin resistance and resulting type 2 diabetes mellitus (T2DM). Here, we aim to study the impact of water fluoride levels on blood glucose and vitamin D levels. A hospital-based study was conducted on diabetic patients (n = 303) at All India Institute of Medical Sciences (AIIMS), Raebareli outstation patient department (OPD). The relationship between vitamin D or fasting blood glucose levels (BGLs) with water fluoride levels was estimated through Spearman's rank correlation. We found a significant negative correlation between water fluoride and vitamin D levels [rs = -0.777, p-value < 0.001] and a positive correlation between water fluoride and fasting BGLs [rs = 0.178, p-value <0.05]. The participants residing in fluoride-endemic areas (F > 1.5 mg/L) had higher odds of severe vitamin D deficiency (odds ratio: 5.07, 95% CI: 1.9-13.2, p-value = 0.0009). The results demonstrate that vitamin D deficiency and fasting BGLs are significantly associated with water fluoride levels. This study signifies the role of fluoride toxicity in poor glycemic control and derived vitamin D deficiency. Vitamin D supplementation and the application of standard household water purification devices are recommended to tackle vitamin D deficiency in fluoride-endemic areas.

Aesthetic problem in the appearance of permanent teeth in children and adolescents - dental fluorosis.

Introduction: Dental fluorosis is a disease caused by excessive consumption of fluoride and its deposition in the enamel during odontogenesis. The result of this process is the appearance on the surface of permanent teeth of unsightly stains of various colors depending on the intensity of damage to the enamel. Deterioration of dental aesthetics can significantly affect the quality of life of patients affected by dental fluorosis.Aim of the study: The purpose of this study is to present contemporary knowledge on the cause, diagnosis and treatment of dental fluorosis.Materials and methods: Medical databases of the National Center for Biotechnology Information/PubMed and Google Scholar were analyzed by typing the following keywords: dental fluorosis, fluoride poisoning, amelogenesis, enamel. When analyzing the literature, data from 25 scientific articles from the last five years (2017-2022) were used.Results: In most of the articles, the authors emphasize the significant association between consumption of fluoridated water and fluorosis of permanent teeth. The literature is unanimous regarding the choice of minimally invasive treatment procedures when dental fluorosis needs to be treated.Conclusions: Dental fluorosis is a significant aesthetic and functional problem among affected children. Education about the etiology of dental fluorosis and ways to avoid it should be constantly disseminated among children's caregivers. Patients affected by this problem should be under the constant care of a dentist.

A single exposure to cancer misinformation may not significantly affect related behavioural intentions

Background: In recent years, rates of online cancer misinformation have grown, with many concerned that this could lead patients to alter their daily behaviours or forego conventional treatment. However, no published study has investigated whether exposure to cancer misinformation can affect health behaviours or behavioural intentions. Method: In this preregistered study, participants (N = 774) were exposed to cancer misinformation in the form of news stories before rating their intentions to engage in related behaviours. Each participant was randomly presented with two of four possible false cancer headlines such as “Drinking fluoridated water shown to increase cancer risk by a factor of 3”, before rating their intentions to engage in certain behaviours (such as avoiding fluoridated water). Participants were also randomly assigned to either an accuracy-nudge intervention intended to reduce susceptibility to misinformation or a control condition with no intervention. Results: Viewing the fake cancer headlines did not significantly affect participants’ behavioural intentions – e.g., those who saw the headline regarding fluoridated water were not more likely to report intentions to reduce their fluoridated water intake. The accuracy-nudge intervention did not affect behavioural intentions. Conclusion: Although cancer misinformation is considered a threat to public health, we conclude that once-off exposures to cancer misinformation may not be sufficient to significantly alter behavioural intentions. We note that claims about the effects of cancer misinformation on behaviour have not been adequately researched and we therefore call for more research into the behavioural effects of cancer misinformation exposure, particularly repeated exposure or information passed from trusted sources.

Rare metals recycling from spent NCM cathode materials and simultaneous dehydrofluorination of polyvinylidene fluoride (PVDF) in subcritical water

Several studies have examined the recovery of lithium (Li), nickel (Ni), cobalt (Co), and manganese (Mn) from used lithium-ion batteries (LIBs). However, the environmentally friendly and cost-effective leaching and efficient separation of rare metals from the active cathode material of LIBs remains a challenge. In this study, we present a novel route for the extraction of high-value metals from the NCM cathode material of spent LIBs using subcritical water-containing polyvinylidene fluoride (PVDF). The experimental parameters such as reaction temperature, time, liquid–solid and mass ratios, were carefully investigated. The raw cathode material and the solid residues before and after leaching were characterized using ICP-OES, XRD, FT-IR and SEM-EDS analyses. Results showed that the maximum extraction efficiencies of Li, Ni, Co, and Mn of (98.69, 98.24, 97.52, and 99.04) %, respectively, were achieved under the optimized conditions of 350 °C, 2 h, 1:3 mass ratio, and 60:1 mL/g liquid–solid ratio. Meanwhile, the experimental results of leaching kinetics revealed that the reaction in the system was controlled by the surface chemical reaction model with the linear fitting degree of (R2 = 0.97–0.99) and the calculated activation energies of 63.72 kJ/mol (for Li), 73.55 kJ/mol (for Ni), 74.99 kJ/mol (for Co), and 71.88 kJ/mol (for Mn). The overall findings of this research concluded that the PVDF-assisted subcritical water extraction process is a beneficial and a promising alternative to other existing methods.

Synthesis and structural characterization of copper nanoparticles doped activated carbon derived from coconut coir for drinking water purification

Modifying and functionalizing activated carbon using metal nanoparticles have received great scientific attention in recent decades as a method to improve its inherent properties. The synergistic effects between the dopant and the activated carbon could lead to advanced properties in the hybrid material compared to individual counterparts. In this study, copper-doped activated carbon from coconut coir (Cu-ACC) is synthesized by an in-situ reduction method. The successful doping of zerovalent copper nanoparticles (Cu np) into the activated carbon matrix was confirmed using several characterization techniques. Peaks related to zerovalent Cu np in the X-ray diffractogram confirmed the successful formation of zerovalent Cu np. The dopant-matrix interactions were confirmed through peak shifts in the Fourier Transform Infrared Spectroscopy and D and G band changes in the Raman spectrum of Cu-ACC. The Cu 2p band in XPS of the Cu-ACC showed a sharp doublet at 932.7 eV, confirming the presence of metallic Cu. As indicated in the TEM/SEM images, Cu np demonstrated a spherical morphology with an average diameter of 5 nm. It was further observed that the Cu-ACC nanohybrid material could remove fluoride (63%) and hardness (69%) in synthetic water. Cu-ACC further demonstrates an enhanced antimicrobial activity against three commonly found water pathogens; E. coli, S. typhi, and S. flexneri. The material is expected to be used in next-generation domestic water filters formulated as single-use sachet bags.

Defluoridation potential of indigenous thirst-quenching herbal products commonly used in Kerala, India

Background: Drinking fluoride-contaminated water is a severe health hazard problem. Fluorosis -both skeletal and dental- is an important clinical and public health problem in about 24 countries including India. The best method to overcome the problem of excess fluoride in drinking water is defluoridation. Adsorption methods are simple, economical, and globally pursued techniques. Thirst-quenching herbal products locally called ‘Dahashamini’ are plant parts that are used during boiling drinking water. Possessing a defluoridation potential is an added benefit. Methods: Two grams of each of dried and ground Zingiber officinale, Elettaria cardamomum, Eugenia caryophyllus, Coriandrum sativum, Acacia catechu, Caesalpinia sapans, Vetiveria zizanioides, Cuminum cyminum, and Hemidesmus indicus, were added to 100 millilitres of fluoridated water of baseline concentrations of 5 and 10 ppm, boiled till its boiling point, and cooled. The samples were then filtered and analyzed for fluoride content using fluoride ion specific electrode method. Statistical analysis was done using one-way ANOVA, followed by Tukey’s post hoc test for pair-wise comparison. Results: Caesalpinia sapans, Vetiveria zizanioides, Acacia catechu, Eugenia caryophyllus, and Coriandrum sativum, had a significant ability to adsorb fluoride from fluoridated water, with an efficiency ranging from 12% to 56% (at a baseline concentration of 10 ppm) and 19% to 82% (at a baseline concentration of 5 ppm). Conclusion: The study indicates the possibility of the use of five ingredients in developing a cost-effective and acceptable method of defluoridation based on the adsorption method.

Mapping the evidence for monitoring fluoride exposure in community prevention programmes for oral health using nail clippings and spot urine samples: a scoping review.

There is an increased interest in identifying practical and accurate biomarkers for fluoride exposure. Due to the narrow 'dose-gap' between the benefit of caries reduction and the risk of dental fluorosis, monitoring of fluoride exposure is vital when introducing any fluoridation programme for the prevention of dental caries. This scoping review aimed to ascertain the nature and extent of the available evidence on how spot urine and nail clippings are used to measure fluoride intake/exposure, by using a unique approach of mapping the studies according to population, setting, type of study design, methodology and analytical approach in community prevention programmes. Multiple relevant databases were searched up to July 2021 for any study designs, including randomised controlled studies, quasi-experimental studies, surveys, retrospective and prospective cohort studies, case studies, phenomenological studies, and expert opinions. The search retrieved 9,222 studies of which 155 met the inclusion criteria. A high proportion of the studies (25.2%) originated from Latin America and the Caribbean continent subregion. However, per country, China recorded the highest number, followed by India and Mexico. The majority (62.6%) employed a cross-sectional study design, and 65.8% combined participants from different age groups. Of the included studies, 82.6% used spot urine samples as a biomarker for assessing fluoride intake/exposure. Water fluoride concentration was reported in 66.5% of the studies with 46.6% of all included studies reporting a water fluoride concentration of > 1.2mg/L. The methods used in assessing oral hygiene and dietary intake were not reported in 72.3% and 71.0% of the included studies, respectively. Only 35.5% of the included studies assessed the relationship between fluoride exposure and excretion. This review revealed a large variability in the way in which spot urine samples and/or nail clippings are used to measure fluoride exposure in different settings and situations. Particularly, there are inconsistencies in the methodologies and the analytical approaches used in assessing fluoride exposure. Therefore, there is a need for more rigorous primary research studies using standardised approaches to determine the suitability of spot urine samples and nail clipping as biomarkers for monitoring fluoride exposure.

Plaster board waste (PBW) – A potential fluoride leaching source in soil/water environments and, fluoride immobilization studies using soils

Plaster board waste generated from industries, usually contains major proportion of calcium as calcium sulfate. In addition, fluoride is remarkably one among the constituents of this waste material which leaches off into the soil and aquatic environments and causes fluoride pollution. In order to simulate how the dumping of PBW causes fluoride contamination in soil and water sources, shaking and stirring based batch-mode leaching studies were conducted. These studies explored the leaching of fluoride as a function of particle size, agitation time, pH of the leaching solvent (distilled water), L/S (water: PBW) ratio, temperature and electrolytes. It was explored that 1 g of plaster board waste contains18.54 mg F per gram of PBP. High leaching of 3.72 mg F per liter was studied at pH 6.02 with Ca2+ and TDS contents of 1050 mg L−1 and1640 mg L−1 respectively. The influence of sodium electrolytes such as chloride, nitrate, hydrogen carbonate, carbonate, sulfate, borate, phosphate and acetate on the leaching of fluoride from PBW was studied. The influence of fluoride leaching by sodium phosphate recorded a high value of 12.75 mg L−1 with no detectable amount of calcium ions. The influence of eight electrolytic mixtures each containing five sodium electrolytes on fluoride leaching corroborated the highest leaching in mixtures containing phosphate followed by hydrogen carbonate/carbonate. Solutions of calcium and aluminium chloride and their mixture were used to measure the rate of leachable fluoride in solution. Furthermore, the fluoride leaching at different temperatures and acids was studied. Naturally occurring soils when blended with PBW were observed to immobilize fluoride and lessened the amount of leaching fluoride in water. Various characterization studies such as FTIR, Raman, FESEM (with EDS), XRD and XPS were carried out for PBW and its treated samples using different electrolytes. Fluoride leaching proportionate to the precipitation of carbonate and phosphate was recorded in the case of appropriate electrolyte and mixtures.

BFS welcomes Ministerial intention to proceed with Community Water Fluoridation

BFS welcomes Ministerial intention to proceed with Community Water Fluoridation

α-Lipoic Acid Alleviated Fluoride-Induced Hepatocyte Injury via Inhibiting Ferroptosis.

Fluoride is widely used in agricultural production and food packaging. Excessive fluoride in water and food is a serious threat to liver health. α-Lipoic acid, a natural free radical scavenger, has hepatoprotective properties. However, the protective effect of α-lipoic acid on fluorohepatotoxicity is uncertain. The aim of this study was to investigate the mechanism of ferroptosis in α-lipoic acid preventing fluoride-induced hepatotoxicity. Five-week-old ICR mice were treated with sodium fluoride (100 mg/L) and/or α-lipoic acid (200 mg/kg) for 9 weeks. The results showed that α-lipoic acid attenuated fluoride-induced damage to liver morphology and ultrastructure. Moreover, α-lipoic acid alleviated fluoride-induced iron accumulation, increased oxidative stress, and elevated lipid peroxidation in the liver. In addition, the mechanism study found that α-lipoic acid prevented fluoride-induced ferroptosis through the System Xc-/GPX4 axis, lipid peroxidation axis, and iron metabolism axis, but it was interestingly not regulated by mitochondrial free radical axis in the hepatocytes. Altogether, this study indicated that α-lipoic acid prevents fluoride-induced liver injury by inhibiting ferroptosis, which has potential implications for the prevention and treatment of fluoride-induced liver injury.

Who are the 10%? Characteristics of the populations and communities receiving fluoridated water in England.

In England, around 10% of the population receive optimally fluoridated water. This coverage has evolved through a combination of historical local decision-making and natural geography, rather than being strategically targeted at the national level. It is important to understand if the current distribution is equitable according to indicators of oral health need and to identify any population-level differences in socio-demographic characteristics that could introduce bias to studies evaluating the effectiveness of water fluoridation. Descriptive analysis comparing the census characteristics of populations that received optimally fluoridated (=/⟩ 0.7 mg F/L) and non-fluoridated water (⟨0.7 mg F/L) between 2009 and 2020. Populations receiving fluoridated water between 2009-2020 were on average slightly younger, more urban, more deprived, with lower education levels, higher unemployment and lower car and home ownership than the populations who received non-fluoridated water. They are more ethnically diverse, with a higher proportion of Asian ethnicity and a lower proportion of White ethnicity, compared to the non-fluoridated population. This descriptive analysis provides evidence that water fluoridation coverage within England is targeted reasonably equitably in relation to population-level indicators of need. It also confirms the need to consider the impact of underlying differences in age, deprivation, rurality, and ethnicity when evaluating the impact of water fluoridation on health outcomes in England.

Removal of fluoride from aqueous solutions through Fe(III) modified water treatment residues

The extensive presence of fluoride (F−) in ground and surface water poses a potential threat to human health. Water treatment residues (WTR) are potential absorbents that can remove F−, but this removal capacity needs to be enhanced further for its optimal utilization. In this study, we have proposed a method of Fe-modified WTR (Fe-WTR) to ameliorate removal efficiency and investigated the associated mechanism. The physicochemical properties of Fe-WTR were characterized using X-ray fluorescence spectrometry (XRF), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The maximum adsorption capacities of WTR and Fe-WTR for F− reached 6.09 and 16.09 mg/g under natural pH (pH = 6.5). The F− adsorption kinetics most suitable model was the pseudo-second-order model, indicating that the chemical adsorption may play a primary role in the F− removal process. A probable mechanism for F− adsorption by Fe-WTR was proposed, where the complexation reaction of F− with Al3+ and Fe3+ and ion exchange of F− with OH− were the main processes. The excellent resistance to interference from coexisting anions and the change in pH value clearly demonstrates that Fe-WTR can be efficiently applied for various environments. To conclude, owing to its high adsorption capacity, economy, and environmental friendliness, Fe-WTR is a potentially efficient adsorbent for F− removal from polluted waters. Moreover, this study presents a deeper understanding of the mechanism of F- removal by WTR, which may pave way for future appropriate modifications of WTR for future applications.

BFS welcomes Ministerial intention to proceed with community water fluoridation

BFS welcomes Ministerial intention to proceed with community water fluoridation