Fluoride Concentration In Samples Research Articles

Fluoride intake via watermelon consumption and risk assessment

Natural fruit beverages are popular drinks worldwide. In particular, watermelon juice is highly consumed in the Middle East because the geographical conditions are suitable for its cultivation. However, the innocuity of these beverages is poorly studied in the region. In this study, the fluoride concentration in natural watermelon juice from 3 different provinces of Iran was determined. The toxicological risk of fluoride for watermelon consumers with an age range of 4-65 years old was also determined. The fluoride content in 30 watermelon samples was analyzed. The mean values of triplicate fluoride measurements were reported in this study. The health risk assessment was evaluated by using the hazard quotient (HQ). Overall, the mean fluoride content in natural watermelon juice was 0.007 mg/L. The mean fluoride concentration in samples from Fars province (with the highest value of 0.037 mg/L) was statistically higher than that from Khuzestan and Isfahan provinces. The hazard quotient value in all age groups was <1 and indicated no significant risk for watermelon consumers of the different age groups. Although watermelon alone may not present an apparent health risk, fluoride intake by consuming other sources of drinks and food should be considered to provide a comprehensive fluoride risk assessment.

Fluoride removal in drinking water using activated carbon prepared from palmyrah (Borassus flabellifer) nut shells

Fluoride is a useful ion for human health and fluoride related health problems can occur due to the deficiency or excess intake. Human intake of fluoride is consumed mainly from drinking water. The removal of fluoride ions from its aqueous solutions and water samples using activated carbon, was conducted in this study. For the preparation of activated carbon dried palmyrah (Borassus flabellifer) nut shells were used as a low cost adsorbent. Activation of dried palmyrah nut shell charcoal was done with concentrated H3PO4 and 25% NaOH separately as activating agents. Characterization of the non-activated carbon (NAC), phosphoric acid activated carbon (PAC) and sodium hydroxide activated carbon (SHAC) was conducted using different parameters. Fluoride removal efficiency of PAC was investigated for a synthesized fluoride solution which was prepared using NaF and deionized water in four different conditions such as contact time, adsorbent dosage, initial fluoride concentration and temperature. Fluoride concentration in samples was measured by SPADNS method. Then seven different field water samples were collected from Nochchiyagama area, Anuradhapura district which is a major fluoride contaminated ground water containing area in Sri Lanka. The physicochemical characteristics of PAC was found to be high compared to NAC and SHAC.Optimum conditions for the highest fluoride removal efficiency of PAC were observed as 45 ​min contact time, 0.2g adsorbent dosage, 1 ​mg/L initial fluoride concentration at 30 ​°C temperature with 61% adsorption efficiency. The pseudo-first order and pseudo second order kinetic models were applied in this experiment. The pseudo second order exhibited the best fit for the kinetics studies that indicates the chemisorption process. The experimental isotherm data were analysed by different models; the adsorption follows the Freundlich model providing better fit for the equilibrium data. PAC from palmyrah nut shells would make an alternative source of activated carbon and low cost adsorbent for the fluoride ions.

FLUORIDE CONCENTRATION AND OTHER ELEMENTS IN TOOTH STRUCTURE AND ITS EFFECT ON DENTAL CARIES IN KIRKUK, IRAQ

The study involved the determination of fluoride and other elements like Mn, Na, Mg, Si, K, Ca, Fe, Al, Cl and some trace elements (Cr, Cd, Ni, Zn, Pb, Sr, As, Co, Cu, Mo and Se) in 220 teeth samples with age group ranging from 6–45 year. The average concentration of fluoride in samples were less than the global average, and the total contents of fluoride in the children deciduous teeth are relatively higher than that of permanent teeth. The infection rate of dental caries in children seen in age between 6–11 years and increasing after the age of 12 due to certain environmental factors, age, water and food quality, so there is a strong relationship between the rising amount of fluoride concentration in the area and reducing the rate of dental caries. The study also determines the different limits and importantly the optimum value of fluoride concentration in drinking water of Kirkuk City which is done by correlation with the mean value of the maximum daily temperature of the city over the last five years, and also taking in consideration that human gets the fluoride from a different source such as food, air and tooth paste, so we correlate our finding with the rate of fluoride taken from other sources which not greater than 6mg/day, according to World Health Organization (WHO), in order to avoid the hyper fluorosis (excess fluoride).

Geochemistry of high concentrations of fluoride in groundwater at Oued Rmel aquifer (North-eastern Tunisia), and risks to human health from exposure through drinking water

The Oued Rmel aquifer, in Zaghouan city in north-eastern Tunisia, extends geographically between 36°18′ and 36°26′ North, and between 10°06′ and 10°24′ East. The groundwater of the Oued Rmel aquifer is exploited for drinking and irrigation purposes. To monitor the chemical water quality, and especially to identify the occurrence and behaviour of fluoride, 23 water samples were collected in January 2013, and analysed for chemicals parameters such as Na+, Ca2+, Mg2+, K+, Cl−, SO42−, HCO3− and F−. This study applied conventional techniques such as hydrochemical compositions, multivariate statistical methods, Geochemical Modeling and Geographical Information Systems (GIS). Concentrations of fluoride in samples from the Oued Rmel aquifer ranged from 4 to 22 mg/L. The highest values were observed in the surroundings of hydrothermal sources, especially from Hammam Zriba and Hammam Djedidi. Compared with international and national guidelines, all analysed samples exceeded the maximum permissible concentration, in drinking water, of WHO and Tunisian Standards (NT.09.14), which are 1.5 and 1.2 mg/L, respectively. Consequently, up to 75% of the population in the region who use groundwater as a source of drinking water are at risk of developing dental or skeletal fluorosis. Thus, the treatment of fluoridated water through methods such as precipitation, ion exchange, electrodialysis, and reverse osmosis is essential.

Fluoride concentration in Peruvian salts determined with specific electrode by the direct method

According to the Peruvian legislation, salt for human consumption should contain 200-250 mg F/kg, but there is limited data showing whether this requirement is being accomplished. Aim: In this pilot study, we evaluated the fluoride concentration in samples of salt marketed in Lima, Peru, using a standardized protocol with ion-specific electrode by direct method (ISE). Methods: Seven 1 kg salt packages of four brands were purchased in two supermarkets of Lima. Six aliquots of each package were weighed and dissolved in the proportion of 0.025 g/mL of water. Duplicates of 1.0 mL of these solutions were mixed with 1.0 mL of TISAB II and fluoride concentration was determined with ISE calibrated with standards fluoride solutions ranging from 0.25 to 16.0 µg F/mL. The ionic strength of the standards was adjusted with p.a NaCL (25 mg/mL). In addition, triplicates of 15 g of each salt package were fractionated in a set of sieves (0.590 to 0.177 mm) to determine the homogeneity of fluoride concentration in salt. Results: In four packages the mean fluoride (mean±SD,n=6) concentration (mg F/kg) was in agreement to the Peruvian regulation (214.5±10.4; 221.8±14.3; 226.9±19.1 and 237.2±52.0 mg F/kg), but in 3 packages it was lower (145.2±7.9; 145.7±23.3 and 158.4±20.6 mg F/kg). Variability in fluoride concentration was observed within the same brand and among brands. Also, the fluoride concentration was not homogeneous in none of the salt samples, ranging from 72.0 to 1449.7 mg F/kg. Conclusion: The findings suggest that the manufacturing and sanitary surveillance of fluoridated salt in Peru should be improved.

Investigation of Fluoride Level in Drinking Water Supplies of Qaemshahr City (North of IRAN) from 2006 to 2012

Background and purpose: Fluoride is one of the fundamental and required components in human body. The current study intends to survey the status of fluoride in drinking water supplies (underground water source and drinking water) in Qaemshahr city from 2006 (march/21) to 2012(march/19) and comparison with universal standards, national and climatic conditions. Materials and Methods: This is a descriptive and sectional study. Samples were experimented in Qaemshahr water and wastewater department laboratory. Fluoride concentration in samples has been measured by DR 2800 and SPADNS Fluoride Reagent Solution. Results were analyzed with Excel software. The medium of maximum temperature in different seasons has been obtained from meteorology department. Then fluoride levels in several years have been compared to each other and to universal, national and climatic standards. Results: Comparing to standards National standards of IRAN and according to climatic conditions, proper levels of fluoride were in underground water sources respectively (9 % - 0.9 %) in spring, (17 % - 6.5 %) in summer and, (13 % - 0.00 %) in autumn and in winter. Also in Urban water distribution network were respectively (3.2 % - 3.2 %) in spring, (12.5 % - 5 %) in summer, (8.3 % - 0.00 %) in autumn and, (0.00 % - 0.00 %) in winter. The Fluoride levels in 100% of samples were lower than standards (MCLG and MCL= 4 mg/l). Conclusion: No significant relation was observed between fluoride concentrations obtained in different seasons and in different years. In most cases the Fluoride levels in studied city were lower than universal standards, national and climatic conditions. It is recommended that adding fluoride to food chain of the studied citizens should be noticed by the relevant authorities. (*Boudaghimalidareh H. Alinezhad A. Boudaghimmalidareh P. Mahvi A. Investigation of Fluoride Level in Drinking Water Supplies of Qaemshahr City (North of IRAN) from 2006 to 2012. IJHS 2013; 1(2):19-27) http://jhs.mazums.ac.ir

Drinking Water Fluoride Levels for a City in Northern Mexico (Durango) Determined Using a Direct Electrochemical Method and Their Potential Effects on Oral Health

Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations >0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called “fluorosis.” Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313 ± 1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001 ± 2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen.

Total and free available fluoride in toothpastes in Brunei, Cambodia, Laos, the Netherlands and Suriname

This study assessed total and free fluoride concentrations in samples of toothpaste from Brunei, Cambodia, Laos, the Netherlands and Suriname, and investigated the labelling practices of the respective manufacturers. Convenience samples were bought in the five countries and sent for analysis to the Netherlands. Levels of total and free available fluoride were measured. Details of the information declared on the packaging about type of fluoride and abrasives were recorded, and manufacturing and expiry dates were noted. A total of 119 samples of toothpaste were analysed. With one exception, all samples from the Netherlands complied with ISO (International Organisation for Standardisation) labelling requirements and there were no differences between the fluoride content declared and that found to be present on analysis. In samples purchased in the other countries, sodium monofluorophosphate (SMFP) toothpastes predominantly showed a low percentage of free available fluoride and the majority of toothpastes did not follow standard labelling guidelines. This study is not representative of any of the brands analysed, yet it highlights problematic discrepancies in products across countries. These may be related to the lack of a generally accepted methodology for analysing total and free fluoride content, absence of an agreement on the minimum concentration of fluoride required to ensure efficacy, weak regulating institutions that are unable to control labelling and consumer information, as well as a possible influx of counterfeit low-quality toothpaste. Renewed international focus should be directed towards closing gaps in guidelines and standards. Consumers should use only non-expired toothpaste, which should preferably be silica-based fluoride toothpaste that does not include abrasives containing calcium and that is properly labelled.

High-resolution electron microscopy and crystallographic study of some biological apatites

An ultrastructural study of apatite crystal lattice was performed through TEM, dealing with human sound enamel, human enamel with amelogenesis imperfecta, fluorotic enamel, and Selachian enameloid. Measurements were performed on the electron micrographs and submitted to a stereographic projection. A connection between lattice defects and an increase in fluoride concentration in samples was pointed out through X-ray diffraction. The multiplication of dislocations appears to be connected with an increased growth of the crystals as well as with their larger size in fluorotic enamel compared with sound enamel. The clear zones observed within the crystals cannot always be attributed to beam damage. They also might be linked to dislocations or to an early stage of mineralization.

Direct determination of fluoride in miscellaneous fluoride materials with the orion fluoride electrode

The Orion fluoride electrode was used to measure major concentrations of fluoride in samples containing aluminum, calcium and silicon without prior separation. Liquid samples were mixed with a total ionic strength buffer and direct potentiometric readings were compared to a calibration curve. Samples of AlF 3, Na 3AlF 6, CaF 2, and SiO 2 (containing 20% fluoride) were fused with sodium carbonate and dissolved in water or a total ionic strength buffer. For samples containing alumina which may not be rendered soluble by a carbonate fusion, a borate-carbonate fusion was used. Interferences were masked by the addition of equal concentrations of the interfering ion during the preparation of the standards. Results are shown for various samples analyzed by this technique and by the Willard-Winter distillation and titration. The direct method is accurate to within ±3% of the amount present.