Fluorine In Water Research Articles

Effects of soybean, selenium and spirulina on hemoglobin of rats intoxicated with fluorine and aluminium

Objective To observe the effects of soybean,selenium and spirulina on hemoglobin(Hb)of rats intoxicated with fluorine and aluminiums.Methods According to body weight,84 SD rats were randomly divided into control group,high aluminum group,high fluorine group,high fluorine-aluminum group,high fluorine-aluminium intoxicated rats strengthened with soybean group,high fluorine-aluminium intoxicated rats strengthened with selenium group and high fluorine-aluminium intoxicated rats strengthened with spirulina group,12 in each group.Rats in the control group and the high aluminum group were fed with feed containing 5.2 mg/kg of fluorine and 6.8 mg/kg of aluminum.In other groups,fluorine wag 106 mg/Kg and aluminum 19.7 mg/kg.Fluorine and aluminum concentration in the drinking water of the control group and the high fluorine group were 0.69 mg/L and 0.20 mg/L,respectively.In other groups' drinking water,these values were 0.69 mg/L and 90.2 mg/L,respectively.Ninety days later,Hb concentration of the whole blood was tested.Results Hb concentration of the control group,the high aluminum group,the high fluorine group,and the high fluorine-aluminum group were (160.8±6.3),(142.2±15.9),(156.1±4.9)and(145.2±6.2)g/L,respectively.Fluorine had an effect on the concentration of Hb(F=29.56,P 0.05).Conclusions High-dose fluorine could cause varied decrease in the concentration of Hb.However,aluminum has neitherantagonistic effect nor synergistic effect on the Hb of fluorotic Rat.Soybean,selenium and Spirulina show a trend to increase fluorotic rat's Hb,but they has no evident antagonistic effect. Key words: Soy beans; Selenium; Spindina; Fluorine; Aluminum; Hemoglobins

Determination of fluoride as fluorosilane derivative using reversed‐phase HPLC with UV detection for determination of total organic fluorine

A quantitative method for fluoride determination using RP HPLC and UV detection was developed. The method is based on the reaction of fluoride with triphenylhydroxysilane in highly acidic conditions and extraction of the reaction product into n-heptane. Chromatographic conditions as well as the derivatization parameters were optimized. LOQ for fluoride ion was evaluated as 0.25 μM (4.75 ppb) and linear range of response up to 75 μM (1.42 ppm) was obtained. The method was developed as a part of a procedure designed for the determination of total organic fluorine in natural waters, using SPE on a carbon sorbent and sodium biphenyl reagent for the defluorination reaction. LOD for a model compound, perfluorooctanoic acid, calculated for the complete procedure with 2000-fold preconcentration, is 20 ppt (n=4). Initial results show feasibility of total organic fluorine determination for environmental purposes.

대전시 일부 초등학교 일반교사와 보건교사의 수돗물 불소농도조정사업의 인식도조사

본 연구는 대전광역시 초등학교 110곳을 대상으로 교사 400명에게 방문 또는 우편조사법을 실시하였다. 단순 확률 추출법으로 자기기입식 설문조사를 실시하였고, 그 중 불성실하게 응답하였거나 조사내용 일부가 누락된 자료를 제외한 총 348부를 최종분석에 사용하였다. 연구 결과를 종합해 볼 때 대전시 초등학교 일반교사들의 수돗물 불소농도조정사업에 대한 인식도를 조사하여 학생들에게 구강보건지식과 구강보건관리습관 형성에 중요한 역할을 담당하는 초등학교 교사에게 수돗물 불소농도조정사업에 대한 안정성과 치아우식증 예방 효과에 대한 교육을 실시하여 불소에 대한 정확한 지식과 긍정적인 인식을 가질 수 있도록 하며, 또한 국가나 지방자치단체에서의 제도적 행정적인 뒷받침이 필요하다고 사료된다. 【Approximately 110 elementary schools and 400 teachers in Dae Jeon metropolitan city were chosen for this research, by using the method of direct visit and survey by mail. The survey was performed as in the forms of self administration, by simple statistic extract method, and among the survey, insincere answers and partly omitted contents were removed, which left 348 survey questionnaires to use for the final research. In order to restore the tap water fluorine concentration regulation project in Dae Jeon, advertise its benefits; it offered precise knowledge and positive response of fluorine through education on oral disease prevention, provide correct knowledge, administrative support should follow to support its importance.】

Endemic fluorosis surveillance in Qinan County of Gansu Province from 2004 to 2007: an outcome analysis

Objective To investigate the prevalence of endemic fluorosis and the progress acchieved through control measures in Taian County of Gansu Province so as to provide basis and technique support for endemic fluorosis control. Methods The survey was carried out according to the National Surveillance Scheme of Endemic Fluorosis. Fulfillment of control measures and the quality of water improving projects were surveyed. Samples of household water and urine in children aged 8-12 years were collected and fluoride content was detected by iron selective electrode method. Children's dental fluorosis were examined with Dean method. Results In Qinan County, water was improved in a rate of 100%. In water-improving and defluoridation projects investigated, 81.15% (99/122) projects worked well, 18.85% (23/122) projects were closed or abandoned. The number of water improvement projects monitored were 24,81,9,8,respectively in the year through 2004 to 2007, revealing 13 projects having water fluorine content(>1.0-2.0 mg/L) in 2004, 15 and 5 projects having water fluorine content higher that 1.0-2.0 and 2.0-4.0 mg/L respectively in 2005, 2 projects having water fluorine content(>1.0-2.0 mg/L) in 2006, and no projects above 4.0 mg/L. In Anfu Village, the fluorine content of source and drinking water were all below 1.0 mg/L in 2006 and 2007. The urinary fluoride content of 8-12 years old children was equal and higher than 1.5 mg/L, dental fluorosis rate was 34.47% (354/1027), and dental fluorosis index was 0.65 in 2004-2007. Conclusions Projects running out of status and excessive levels of water fluorine are frequently seen, dental fluorosis is not controlled in Taian County of Gansu Province Key words: Drinking; Fluoride poisoning; Surveillance

Cupro(I)-π-complexes with 1-allyloxybenzotriazole: Synthesis and crystal structure of CuBF4 · 2C6H4N3(OC3H5) · H2O and CuCF3COO · C6H4N3(OC3H5)

The crystals of copper(I) π-complexes CuBF4 · 2C6H4N3(OC3H5) · H2O (I) and CuCF3COO · C6H4N3(OC3H5) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P21/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) A, β = 98.13(1)°, V = 2249(2) A3, Z = 4, R = 0.0705, 577 reflections; I, space group P\( P\bar 1 \) , a = 8.8625(7), b = 9.0647(4), c = 9.1650(5) A, α = 68.37(2)°, β = 85.31(3)°, γ = 69.86(2)°, V = 646(4) A3, Z = 2, R = 0.1354, 2669 reflections. In compound I, the tetrahedrally distorted trigonal pyramidal environment of the copper atom comprises two nitrogen atoms of two organic molecules (L), the C=C bond of another L molecule, and the O atom of the water molecule. Due to the bridging function of L molecule, infinite chains [Cu · 2C6H4N3(OC3H5) · H2O]n are formed in the structure along the y axis. The chains are, in turn, assembled into layers through strong O-H…F hydrogen bonds involving both hydrogen atoms of the water molecule and fluorine atoms of the BF4− anion. In compound II, two bridging oxygen atoms of two trifluoroacetate anions and two copper atoms form a centrosymmetric dimer. The nitrogen atom of the benzotriazole ring of one molecule L and the C=C double bond of the allyl group of the other molecule L complete the distorted coordination tetrahedron of the metal atom. Owing to the bridging function of the L molecule, the [CuCF3COO · C6H4N3(OC3H5)]2 dimers are connected to form infinite double chains associated in a three-dimensional framework by only weak interactions. The replacement of the covalently bonded trifluoroacetate anion by an outer-sphere tetrafluoroborate ion opens up the possibility for metal atom binding to three L molecules simultaneously.

Determination of trace levels of total fluorine in water using combustion ion chromatography for fluorine: A mass balance approach to determine individual perfluorinated chemicals in water

Perfluorinated compounds (PFCs) such as perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have received worldwide attention because of their environmental persistence and widespread distribution. Because of the lack of robust analytical methods and standards to detect all of the PFCs, and their precursors and metabolic intermediates, a mass balance approach involving the determination of total fluorine (TF), followed by fractionation of samples to separately determine inorganic and organic fluorine, is needed. In this study, we have developed a method to determine low μg/L levels of total fluorine (TF) in seawater samples. Further, seawater samples were fractionated into organic and inorganic fractions by extraction with organic solvents, which were then analyzed for TF, extractable organic fluorine (EOF) and inorganic fluorine (IF; i.e., fluoride). Concentrations of known perfluorinated compounds (PFCs) including PFOS and PFOA were also determined in water samples by liquid chromatography–tandem mass spectrometry (LC–MS/MS) to enable calculation of the fraction of fluorine that is contributed by PFCs to TF. A major proportion of fluorine in seawater was in the form of fluoride (>90% in locations not affected by direct discharges). Nevertheless, within the organofluorine fraction, a major percentage (60–90%) of fluorine still remains unknown in water samples, suggesting the occurrence of other fluorinated acids in addition to known perfluorinated acids. Further studies are needed to identify and quantify the unidentified organofluorines in seawater. Mass balance analysis of total organic fluorine (TOF) and EOF is important, if we are to understand transport and fate of fluorinated compounds in the environment, and if we are to identify the sources of unidentified fluorinated compounds.

Bis(tetramethylammonium) di-μ-fluoro-bis[aquatetrafluorohafnate(IV)

The HfIV atoms in the centrosymmetric title compound, (C4H12N)2][Hf2F10(H2O)2], are bridged by two F atoms. The HfIV atoms show penta­gonal–bipyramidal coordination. The dianions are linked by water–fluorine hydrogen bonds into layers.

Durability of Irradiated Polymers in Solid-Polymer-Electrolyte Water Electrolyzer

The durability of irradiated organic polymers in solid-polymer-electrolyte water electrolyzer was investigated by gamma-ray irradiation tests around 500 kGy. Serious deteriorations for the tensile strength and ion exchange capacity of the ion exchange membrane (Nafion®) were not observed up to 850 kGy. No serious damage was also observed for tensile strength of the gasket materials (Aflas®) up to 500 kGy. The insulator materials (PFA and FEP) lost their tensile strength at 200 kGy and 300 kGy, respectively. From the above results, we can safely say that the electrolysis cell could be used up to around 500 kGy of irradiation conditions in the case where PFA and FEP are replaced by the polyimide resin which durability against the irradiation is well demonstrated. Two degrading mechanisms were supposed as the effect of irradiation. One is the direct degradation of the chain and branch by gamma-ray. The other is degradation by the attack of radicals. It was demonstrated that the effect of radicals on degradation of the membrane was not dominant. In addition, oxygen was observed to have a large influence on degradation. The quantity of dissolved fluorine in water that could be measured easily was found to correlate closely with tensile strength and ion exchange capacity. Hence, it is possible to evaluate the degradation of ion exchange membrane by monitoring the quantity of dissolved fluorine in water. Concerning the difference of degrading mechanism of the ion exchange membrane due to irradiation source, the combinations of tensile strength, ion exchange capacity and quantity of dissolved fluorine are proposed as deterioration indexes.

Durability of Irradiated Polymers in Solid-Polymer-Electrolyte Water Electrolyzer

The durability of irradiated organic polymers in solid-polymer-electrolyte water electrolyzer was investigated by gamma-ray irradiation tests around 500 kGy. Serious deteriorations for the tensile strength and ion exchange capacity of the ion exchange membrane (Nafion®) were not observed up to 850 kGy. No serious damage was also observed for tensile strength of the gasket materials (Aflas®) up to 500 kGy. The insulator materials (PFA and FEP) lost their tensile strength at 200 kGy and 300 kGy, respectively. From the above results, we can safely say that the electrolysis cell could be used up to around 500 kGy of irradiation conditions in the case where PFA and FEP are replaced by the polyimide resin which durability against the irradiation is well demonstrated. Two degrading mechanisms were supposed as the effect of irradiation. One is the direct degradation of the chain and branch by gamma-ray. The other is degradation by the attack of radicals. It was demonstrated that the effect of radicals on degradation of the membrane was not dominant. In addition, oxygen was observed to have a large influence on degradation. The quantity of dissolved fluorine in water that could be measured easily was found to correlate closely with tensile strength and ion exchange capacity. Hence, it is possible to evaluate the degradation of ion exchange membrane by monitoring the quantity of dissolved fluorine in water. Concerning the difference of degrading mechanism of the ion exchange membrane due to irradiation source, the combinations of tensile strength, ion exchange capacity and quantity of dissolved fluorine are proposed as deterioration indexes.

Research on relationship between fluorine in tap water and that in urine of Chinese residents

In this study, the relationship between fluorine in drinking water and that in urine of urban residents in China is assessed. Fluorine concentrations in tap water and those in urine show a good correlation with a linear regression coefficient of 0.9798, indicating that the fluorine concentrations in big cities under investigation are extremely low, and the main source of fluorine is tap water. The weather effect on the intake amount of fluorine is also discussed. When air temperature is above 15℃, people would intake more fluorine through drinking water with the rise of air temperature. When temperature is below 15℃, no remarkable relationship is observed between air temperature and the intake amount of fluorine. This phenomenon indicates that the main source of fluorine in China is tap water instead of foodstuff.

Relationship between fluorine in drinking water and dental health of residents in some large cities in China

In this project, the relationship between fluorine content in drinking water and dental health of residents in some large cities in China was evaluated. The concentration of fluorine in tap water and in urine of local subjects of 28 cities and 4 high fluorine villages in China shows a strong positive correlation ( r 2=0.96, S.E.=0.9881). Our studies indicate that drinking water is the most important source of fluorine intake for Chinese people, and in more than 90% of urban cities, fluorine concentrations in drinking water are below levels recommended by the WHO (approximately 0.5–1.0 mg/l). A 1995 investigation by The National Committee on Oral Health of China (NCOH) shows the relationship between average number of decayed, missing and filled teeth (DMFT) of urban residents and fluorine concentration in drinking water to be negatively correlated but not forming a good linear relationship. Our results, together with the previous study, suggest that: (1) dental caries of the study population can be reduced by drinking water fluoridation and that (2) other factors such as economic level, weather, lifestyle, food habits, living condition, etc., of a city can also affect the incidence of dental caries that cannot be predicted by fluoridation alone. Research on the relation between index of fluorosis (IF) and the fluorine concentration in drinking water for the four high fluorine villages showed that the recommended concentration of fluorine in drinking water can protect from dental fluorosis.

VALIDACIÓN DEL MÉTODO POTENCIOMÉTRICO POR IÓN SELECTIVO PARA LA DETERMINACIÓN DE FLÚOR EN SAL, AGUA Y ORINA

Objective: To validate the ion-selective potentiometric method for fluorine determination. Materials and methods: Three different samples (salt, water and urine) were analyzed; 3 analysts took part in the water and salt determination and 2 in the urines. The validation was done in 2 days, having performed 10 trials/day. The accuracy, in terms of reproducibility and repeatability, and the precision of the method (in terms of recovery of the analyte added to the sample) were determined. Results: A Relative Standard Deviation (RSD) of 2,68%, 3,29% and 2,52% in salt, water and urine was obtained, and it was also possible to recover 98,20%, 99,42% and 98,11% of the analito for the same salt, water and urine samples. Conclusion: The ion-selective potentiometric method, if used in optimal and appropriate conditions, can be useful to determine fluorine in salt, water and urine samples.

Environmental geochemistry of fluorine in the rock-soil-water system in the karst region of central Guizhou Province

Systematic determination of and adsorption experiment on fluorine in the carbonate rock-soil-water system in the karst region studied in Guizhou Province, in conjunction with the mineral surface and soil chemistry data, have revealed the geochemical characteristics of F and the mechanisms of its transport and enrichment in the rock-soil-water-system of the karst region, central Guizhou Province. Deep-seated underground waters (−100m or lower) and soil layers in the karst region of central Guizhou are characterized by high-F anomalies whereas shallow-level underground and surface waters by low contents of F (mostly lower than 0. 5 mg/ L). Fluorine in soil and water in the region studied comes largely from Triassic marine strata dominated by gypsum-bearing carbonate rocks. The special adsorption and desorption of F on the surface of geothite in soil layers are the important mechanisms of its transport and enrichment in the rock-soil-water system of the karst region studied.

Fluorosis dental: recuento de Streptococcus mutans en escolares provenientes de la Primera Región de Chile. Estudio longitudinal

Background: High fluorine concentrations in drinking water are associated with a decrease in the amount of salivary S mutants. Taking into account that clinical dental fluorosis can appear with 1.5 ppm of fluorine in the drinking water, fluorine concentration in Mamina is 2.4 ppm. Aim: To quantify salivary S mutans in school age children from Mamina, a zone with a high fluorine content in the drinking water, during one year. Material and methods: During 1997 and 1998, dental health was assessed and salivary samples were obtained from 51 children (27 male) aged 10 ± 2 years to quantify S mutans. Results: Most children studied had more than 105 salivary S mutans colony forming units. No changes in the rates of infection or dental health characteristics were observed during the observation year. Conclusions: High fluorine content in the drinking water did not have an effect on salivary S mutans infection in this population.

Simultaneous determination of fluorine and chlorine in water with double indicative electrodes

The new method for simultaneous determination of the concentrations of fluorine and chlorine in river water with double indicative electrodes is developed, and the quantitative analysis formulas that the inputs of electrode were exchanged by using self-made joints were induced. With this method, the synthetic water samples and the water samples taken from Majiagou River were analyzed. The results of determinations are satisfactory. The relative errors were <10.0% for F− and <3.0% for Cl-. The recoveries were 90–101% for F− and 90–110% for Cl−. The relative standard deviations were < 15.2% for F− and < 10.0% for Cl−. The advantages of this method is accurate, rapid and simple.

Fluorine in formation waters, Alberta Basin, Canada

Fluorine is a common minor constituent of formation waters throughout the Alberta Basin, and it was detected in each of the 469 samples analyzed for it. Contents range up to 22 mg/l, with an arithmetic mean of 1.83 mg/l and a median value of 1.20 mg/I. There is a trend toward increased mean and median contents of F from the shallower, cooler, less saline formation waters to the deeper, hotter, more saline formation waters. This trend parallels a trend of increasing saturation with respect to fluorite, with most of the less saline formation waters being undersaturated with respect to fluorite. At the same time, the major portion of F occurs as F − in the less saline formation waters, with increasing amounts held as MgF + as the Ca content, ionic strength and temperature increase. Complexes between Al and F, and VO and F account for only a relatively minor portion of the complexed F. A significant portion of the F in high-salinity formation waters from marine strata could well have originated from the initial seawater. However, it is speculated that water-rock reactions with bentonite or bentonitic shales may have to be invoked to account for the very high contents of F in the less saline formation waters from some of the shallow, cooler, non-marine aquifers of the Upper Cretaceous post-Colorado aquifer-aquitard system. Finally, it is possible to use knowledge of the distribution of F in formation waters from individual aquifers to check on the “correctness” of F determinations (primarily when formation waters of similar composition show saturation with respect to fluorite), and in the same case to predict the F content of formation waters in the Alberta Basin for which only the appropriate major ions have been determined.

Role of barium chemical modifier in the determination of fluoride by laser-excited molecular fluorescence of magnesium fluoride in a graphite tube furnace

Some improvement in the determination of fluorine in urine and tap water by use of laser-exicted molecular fluorescence spectrometry of magnesium monofluoride in a graphite tube furnace has previously been reported. The use of barium as a chemical modifier increased the size of the signal by a factor of 100. The work reported in the present paper was carried out in an attempt to elucidate the mechanism of the enhancement of the magnesium fluoride fluorescence by barium, and to explain some other experimental characteristics of the method, such as the vaporization temperature, which was lower at 1800 °C than the 2400–2700 °C reported by other workers. The mechanism of formation of gaseous magnesium fluoride molecules from sodium fluoride and magnesium nitrate solutions in a graphite tube furnace during atomic absorption measurements was investigated with and without the presence of barium. It was shown that, without chemical modification, the formation of magnesium fluoride in the gaseous phase proceeded mainly via interaction between magnesium difluoride molecules and excess of free magnesium atoms [Mg(g)+ MgF2(g)→ 2MgF(g)]. The efficiency of this process was fairly low, primarily because of the difference between the vaporization temperatures of the reacting species (1400 °C for magnesium difluoride and 1800 °C for magnesium vaporized as magnesium oxide). The presence of barium changed the mechanism of formation of magnesium fluoride. It was calculated that the formation of barium difluoride, rather than magnesium difluoride, was thermodynamically preferable in the first step of the mechanism. Experimental data indicated that the formation of magnesium fluoride then proceeded with higher efficiency than without barium because the reaction Mg(g)+ F(g)→ MgF(g) followed the appearance of magnesium from magnesium oxide, and fluorine from barium difluoride at coincidental temperatures in the range 1700–1900 °C.

Fluor: potenciales efectos adversos

Prolonged fluorine intake can cause skeletal fluorosis, which may affect teeth, bone tissue and secondarily the nervussislem. Growth, previous exposure to fluorides, malnutrition, inanition, acid urinary pH, enhance fluorine retention in thebody. In subacule and chronic fluorine exposure there are detectable skeletal changes (in the epiphyses of longbones,skull and cervical spine). Cost benefit ratio should be considered when fluorides are prescribed, including thehigher susceptibility of children to fluorosis, terotogenecity and the presence of mentioned risk factors. In this countryinvestigations are needed on real needs of fluorine among diferent regional communities, and appropriate knowledge onthe concenlralions of fluorine in drugs, tooth pastes, waters and foods is urged before decisions that involv e indiscriminatedfluoridalion of waters are to be taken.[Key words: fluorine, fluoridalion, fluoride poisoning, fluorides topical.!

Fluorine distribution in waters of Nalgonda District, Andhra Pradesh, India

Geochemical and hydrochemical studies were conducted in Nalgonda District (A.P.), to explore the causes of high fluorine in waters, causing a widespread incidence of fluorosis in the local population. Samples of granitic rocks, soils, stream sediments, and waters were analyzed for F and other salient chemical parameters. Samples from the area of Hyderabad city were analyzed for comparison. The F content of waters in areas with endemic fluorosis ranges from 0.4 to 20 mg/l. The low calcium content of rocks and soils, and the presence of high levels of sodium bicarbonate in soils and waters are important factors favoring high levels of F in waters.

Determination of fluorine in urine and tap water by laser-excited molecular fluorescence spectrometry in a graphite tube furnace with front-surface illumination

Calculations of the coherent production of free pairs and of pair production with electron capture from ultrarelativistic ion-ion collisions are discussed. Theory and experiment are contrasted, with some conjectures on the possibility of new phenomena. 29 refs., 5 figs., 1 tab.