Fluoride Levels In Drinking Water Research Articles

A Cross-Sectional Study to Find the Correlation between the Level of Fluoride in Drinking Water, Dental Fluorosis and Associated Risk Factors- A Original Research.

The present study was conducted to assess the relationship between drinking water fluoride (F) levels, dental fluorosis dental caries, and associated risk factors in the elderly population. A cross-sectional analytical study was conducted on 50 patients aged 25-60 years, selected by stratified random sampling from different areas with different levels of naturally occurring F in drinking water. The patients were assessed for dental fluorosis according to WHO basic survey guidelines. The overall oral health status of the patients was assessed by decayed missing filled teeth DMFT index and the bacterial count of saliva was calculated using the Caries Risk Test (CRT). Statistical analysis was done using mean, standard deviation, standard error, Z-test, Mann-Whitney U Test, and Chi-square test. The results of the present study revealed that the prevalence of fluorosis was 24%. The number of patients with dental fluorosis was highest in those who consumed water with high groundwater fluoride levels irrespective of the source of drinking water. Caries prevalence in the study population was about 5.56 ± 1.95. There was a moderate prevalence of fluorosis in patients, and caries prevalence is high in areas below optimal F areas. Caries prevalence and mean DMFT scores were least common in patients with optimal fluoride levels in drinking water and highest in those with below optimal fluoride in drinking water.

Relationship between COVID-19 severity and fluoride levels of drinking water among children in Karnataka state, India: An epidemiological study

Background: The severity and susceptibility to COVID-19 infection are the two main epidemiological factors influenced by the host and environmental factors. Environmental factors like drinking water fluoride levels have a direct role in depleting Vitamin D and serum calcium level in the body which were found to have a positive effect on the recovery from COVID-19.Aim and Objective: To find out if there is any association between the severity of COVID-19 and ground water fluoride level among children and young adults in Karnataka.Settings and Design: Ecological/Correlational study designMethods: Ground water fluoride levels of districts of Karnataka was obtained from the Government of India Central Ground Water Board’s Ministry of Water Resources River Development and Ganga Rejuvenation Year Book 2016-17 and 2018-19 and data on COVID-19 mortality under the age group of 20 years was obtained from the media bulletin of The Ministry of Health and Family Welfare, Government of Karnataka.Statistical analysis: Descriptive analysis was performed and Pearson’s correlation was used to find out the linear association between the variables.Results: The higher percentage of death due to COVID-19 was observed among males (65.8%) of age 16-20 (52.6%) years and around 71.8% of COVID-19 associated death among children and young adults were not associated with any co-morbidity. The ground water fluoride levels exhibit statistically significant linear strong positive (r=+0.734; P=0.024) correlation with the Case Fatality Rate (CFR).Conclusion: The severity of COVID-19 was observed to be severe in the high concentration of ground water fluoride areas in Karnataka.

Pathways of factors exacerbating dental fluorosis risk at high altitude regions — A review

Many scientific reports emphasized that the extent of prevalence and severity of dental fluorosis is higher among the people residing at high altitude regions than lower altitudes, even though they are exposed to drinking water with similar or less fluoride levels. This review reports various factors which enhance the risk of prevalence and severity of dental fluorosis at high altitude regions through different pathways. Especially, this review focused on ecological, physiological, biochemical and dietary factors as well as to identify potential key areas to implement further research on control of dental fluorosis risk at high altitude regions. In addition, by considering the pathways of risks, suitable remedial measures are also recommended in this review to manage the dental fluorosis risk at higher altitude regions. • Acidosis due to chronic high altitude residence could enhance dental fluorosis. • High fluoride retention occurs due to impaired kidney function at higher altitude. • Need to maintain good nutrition status and intake of alkaline producing diets. • Optimum iodine and vitamin D intake helps to control dental fluorosis. • Need to keep the drinking water fluoride level < 0.1 mg/L at > 1500 m altitude.

Incidence of Fluorosis and Urinary Fluoride Concentration are not Always Positively Correlated with Drinking Water Fluoride Level

The aim of this study was to assess the effect of fluoride on human health, focusing on the incidence of fluorosis, urinary fluoride concentration and fluoride level in drinking water in three fluoride-affected villages of Birbhum district, West Bengal, India. In one village urinary fluoride concentration was very high along with the occurrence of severe dental and skeletal fluorosis, though fluoride level in drinking water was within the permissible limit. The present study suggests that fluoride intake through other sources is also an important contributing factor in fluorosis, corroborating previous reports on high fluoride contents in crops and vegetables grown in fluoride-affected areas.

Age-sex specific disability-adjusted life years (DALYs) attributable to elevated levels of fluoride in drinking water: A national and subnational study in Iran, 2017

National and subnational burden of disease attributable to elevated fluoride levels in drinking water apportioned by sex, age group, province, and community type in Iran, 2017 were quantified based on disability-adjusted life years (DALYs). The attributable burden of disease was estimated using four input data: (1) effect size of elevated drinking water fluoride levels for dental and skeletal fluorosis, (2) population distribution of drinking water fluoride levels, (3) the threshold levels of fluoride in drinking water for contribution in dental and skeletal fluorosis, and (4) age-sex distribution of population. The attributable burden of disease was only related to dental fluorosis, because the fluoride levels were lower than the threshold value for skeletal fluorosis (4.0 mg/L) in all of the cases. The national attributable prevalence (per 100,000 people), DALYs, and DALY rate in 2017 were calculated to be 60 (95% uncertainty interval 48–69), 3443 (1034–6940), and 4.31 (1.29–8.68), respectively. The national attributable burden of disease was not significantly different by sex, but was affected by age and community type in a manner that the highest DALY rate was related to the age group 10–14 y (6.06 [1.82–12.21]) and over 66% of the national attributable DALYs occurred in rural communities. The attributable burden of disease occurred only in 10 out of 31 provinces and about 94% of the attributable DALYs were concentrated in four provinces Fars (1967 [592–3964]), Bushehr (414 [124–836]), West Azarbaijan (400 [120–808]), and Hormozgan (377 [113–761]). Implementation of fluoride-safe drinking water supply schemes in the four leading provinces can prevent most of the national health losses and partly compensate the increasing trend of disease burden from oral conditions at the national level.

Fluoride and Thyroid Function in Children Resident of Naturally Fluoridated Areas Consuming Different Levels of Fluoride in Drinking Water: An Observational Study.

Background:Literature shows association between systemic fluorides and endocrine disorders especially related to thyroid, with lack of clarity.Aims and Objectives:The aim and objective of this study was to estimate serum triiodothyronine (T3), thyroxin, thyroid-stimulating hormone (TSH), fluoride, calcium, phosphate, and alkaline phosphatase levels among children with normal nutritional status and optimal iodine intake residing in three different ranges of drinking water fluoride levels.Materials and Methods:The present double-blinded, observational trial comprised of 293 children aged between 9 and 13 years consuming naturally fluoridated water of three different ranges: Group I: 0.01–0.6 parts per million (ppm), Group II: 0.7–1.2 ppm, and Group III: 1.3–1.8 ppm. For each child's demographic data, body mass index and Clinical Fluorosis Index were recorded along with serum T3, T4, TSH, fluoride, calcium, phosphate, and serum alkaline phosphatase levels. Data were analyzed using Chi–square test, Kruskal–Wallis test, and repeated measures ANOVA with SPSS 23.Results:For serum TSH levels, 40% of children in Group I had deranged levels followed by Group III (20%) and Group II (16%). For serum T4 levels, 24% of children of both Groups I and III had deranged levels followed by Group II (20%). Intergroup correlation of drinking water fluoride levels to the number of deranged serum T3, T4, and TSH of the children showed nonsignificant association. Serum T3, calcium, phosphate, and alkaline phosphatase levels in all children showed values falling within normal range.Conclusion:According to the present study results, long-term intake of fluoridated drinking water (0.02–1.4 ppm) did not show effect on the thyroid function in children with normal nutritional status and optimal iodine intake.

Fluoride ingestion and thyroid function in children resident of naturally fluoridated areas - An observational study.

BackgroundLiterature shows association between systemic fluorides with water fluoride level above 3ppm and endocrine disorders especially related to thyroid. Aim & Objectives: To estimate serum T3, T4, TSH, Fluoride levels among children with normal nutritional status and optimal iodine intake, residing in three different ranges of drinking water fluoride levels below 3ppm.Material and MethodsPresent double blinded observational trial comprised of 293 children aged between 9-13 years consuming naturally fluoridated water of 3 different ranges: Group I: 0.01 - 0.6ppm, Group II: 0.7-1.2ppm and Group III: 1.3-1.8ppm. For each child demographic data, BMI and Clinical Fluorosis Index were recorded along with serum T3, T4, TSH, Fluoride levels. Data was analyzed using Chi Square, Kruskal Wallis test and Repeated measures of ANOVA with SPSS 23.ResultsFor serum TSH levels 40% of children of group I had deranged levels followed by group III (20%) and Group II (16%). For serum T4 levels 24% of children of both groups I and III had deranged levels followed by group II (20%). Inter group correlation of drinking water fluoride levels to number of deranged serum T3, T4, and TSH of the children showed non-significant association.ConclusionsAccording to the present study results long term intake of fluoridated drinking water (0.02 -1.4 ppm) did not showed effect on the thyroid function in the children with normal nutritional status and optimal iodine intake. Key words:Iodine, nutrition, serum fluoride, systemic fluoride, thyroid function test.

Validating a High Performance Liquid Chromatography-Ion Chromatography (HPLC-IC) Method with Conductivity Detection After Chemical Suppression for Water Fluoride Estimation.

A variety of methods, including the Ion Selective Electrode (ISE), have been used for estimation of fluoride levels in drinking water. But as these methods suffer many drawbacks, the newer method of IC has replaced many of these methods. The study aimed at (1) validating IC for estimation of fluoride levels in drinking water and (2) to assess drinking water fluoride levels of villages in and around Vellore district using IC. Forty nine paired drinking water samples were measured using ISE and IC method (Metrohm). Water samples from 165 randomly selected villages in and around Vellore district were collected for fluoride estimation over 1year. Standardization of IC method showed good within run precision, linearity and coefficient of variance with correlation coefficient R2=0.998. The limit of detection was 0.027ppm and limit of quantification was 0.083ppm. Among 165 villages, 46.1% of the villages recorded water fluoride levels >1.00ppm from which 19.4% had levels ranging from 1 to 1.5ppm, 10.9% had recorded levels 1.5-2ppm and about 12.7% had levels of 2.0-3.0ppm. Three percent of villages had more than 3.0 ppm fluoride in the water tested. Most (44.42%) of these villages belonged to Jolarpet taluk with moderate to high (0.86-3.56ppm) water fluoride levels. Ion Chromatography method has been validated and is therefore a reliable method in assessment of fluoride levels in the drinking water. While the residents of Jolarpet taluk (Vellore distict) are found to be at a high risk of developing dental and skeletal fluorosis.

Spatial distribution mapping of drinking water fluoride levels in Karnataka, India: fluoride-related health effects.

(1) To estimate the concentrations of fluoride in drinking water throughout different zones and districts of the state of Karnataka. (2) To investigate the variation of fluoride concentration in drinking water from different sources, and its relationships to daily temperature and rainfall status in the regional districts. (3) To develop an updated fluoride concentration intensity map of the state of Karnataka, and to evaluate these data in the context of fluoride-related health effects such as fluorosis and their prevalence. Aqueous standard solutions of 10, 100 and 1,000 ppm fluoride (F-) were prepared with analytical grade Na+/F- and a buffer; TISAB II was incorporated in both calibration standard and analysis solutions in order to remove the potentially interfering effects of trace metal ions. This analysis was performed using an ion-selective electrode (ISE), and mean determination readings for n = 5 samples collected at each Karnataka water source were recorded. The F- concentration in drinking water in Karnataka state was found to vary substantially, with the highest mean values recorded being in the north-eastern zone (1.61 ppm), and the lowest in the south-western one (only 0.41 ppm). Analysis of variance (ANOVA) demonstrated that there were very highly significant 'between-zone' and 'between-districts-within-zones' sources of variation (p < 10-5-10-9), results consistent with a substantial spatial variance of water source F- levels within this state. The southern part of Karnataka has low levels of F- in its drinking water, and may require fluoridation treatment in order to mitigate for dental caries and further ailments related to fluoride deficiency. However, districts within the north-eastern region have contrastingly high levels of fluoride, an observation which has been linked to dental and skeletal fluorosis. This highlights a major requirement for interventional actions in order to ensure maintenance of the recommended range of fluoride concentrations (0.8-1.5 ppm) in Karnataka's drinking water sources.

Fluoride exposure in public drinking water and childhood and adolescent osteosarcoma in Texas.

The purpose of this study was to examine the association between fluoride levels in public drinking water and childhood and adolescent osteosarcoma in Texas; to date, studies examining this relationship have been equivocal. Using areas with high and low naturally occurring fluoride, as well as areas with optimal fluoridation, we examined a wide range of fluoride levels in public drinking water. This was a population-based case-control study, with both cases and controls obtained from the Texas Cancer Registry. Eligible cases were Texas children and adolescents<20years old diagnosed with osteosarcoma between 1996 and 2006. Controls were sampled from children and adolescents diagnosed with either central nervous system (CNS) tumors or leukemia during the same time frame. Using geocoded patient addresses at the time of diagnosis, we estimated patients' drinking water fluoride exposure levels based on the fluoride levels of their residence's public water system (PWS). Unconditional logistic regression models were used to assess the association between osteosarcoma and public drinking water fluoride level, adjusting for several demographic risk factors. Three hundred and eight osteosarcoma cases, 598 leukemia controls, and 604 CNS tumor controls met selection criteria and were assigned a corresponding PWS fluoride level. PWS fluoride level was not associated with osteosarcoma, either in a univariable analysis or after adjusting for age, sex, race, and poverty index. Stratified analyses by sex were conducted; no association between PWS fluoride level and osteosarcoma was observed among either males or females. No relationship was found between fluoride levels in public drinking water and childhood/adolescent osteosarcoma in Texas.

Effect of fluoridated water on intelligence in 10-12-year-old school children.

Aim:The aim of the present study was to evaluate the relationship of drinking water fluoride levels with children's intelligence quotient (IQ).Materials and Methods:Water was collected from initially identified endemic fluoride regions according to the geological research of Government of India. Fluoride concentration of the water was assessed by utilizing fluoride ion selective electrode, Orion 9609BN, and categorized on the basis of fluoride concentration into low, medium, and high-fluoride regions, i.e., Virajpet (low fluoride level < 1.2 ppm), Banavara (Medium fluoride level 1.2–2 ppm), and Mastihalli (High fluoride levels > 3 ppm). Government school from all three villages were selected randomly and IQ levels were assessed by using Raven's Standard Progressive Matrices. This test was conducted on each child in the study sample.Results:A significant inverse relationship was found between the fluoride concentration in drinking water and IQ (r value = −0.204; P < 0.000). It was observed that IQ level was negatively correlated with fluoride concentration in drinking water.Conclusion:It is concluded that IQ level was negatively correlated with fluoride level in drinking water. Factors that might affect children's IQ need to be considered, and it is necessary to devise solutions for preventing the harmful effects of excessive intake of fluoride ion to the body.

Fluoride levels and osteosarcoma

Context:Osteosarcoma is a rare malignant bone tumor, commonly occurring in the age group of 10 to 24 years. Recent reports have indicated that there is a link between fluoride exposure and osteosarcoma.Aims:The present study was planned to analyze serum levels of fluoride in patients of osteosarcoma and fluoride content of their drinking water.Settings and Design:The present study was carried out comparing 10 patients of osteosarcoma and 10 healthy volunteers (who served as controls).Materials and Methods:Serum and drinking water fluoride levels were estimated by ion selective electrode.Statistical analysis used:The data were computed as mean ± SD and Student’s t test was applied.Results:Both, the serum and drinking water fluoride levels, were significant by higher in patients with osteosarcoma as compared to controls (P > 0.05, P > 0.001, respectively).Conclusions:These results suggest a link between fluoride exposure and osteosarcoma.

Effect of fluoride exposure on the intelligence of school children in Madhya Pradesh, India.

Objective:To assess the relationship between exposure to different drinking water fluoride levels and children's intelligence in Madhya Pradesh state, India.Materials and Methods:This cross-sectional study was conducted among 12-year-old school children of Madhya Pradesh state, India. The children were selected from low (< 1.5 parts per million) and high (≥1.5 parts per million) fluoride areas. A questionnaire was used to collect information on the children's personal characteristics, residential history, medical history, educational level of the head of the family, and socioeconomic status of the family. Levels of lead, arsenic, and iodine in the urine and the levels of fluoride in the water and urine were analyzed. The children's intelligence was measured using Raven's Standard Progressive Matrices. Data analysis was done using the chi-square, one way analysis of variance, simple linear regression, and multiple linear regression tests. P value <0.05 was considered statistically significant.Results:Differences in participant's sociodemographic characteristics, urinary iodine, urinary lead, and urinary arsenic levels were statistically not significant (P>0.05). However, a statistically significant difference was observed in the urinary fluoride levels (P 0.000). Reduction in intelligence was observed with an increased water fluoride level (P 0.000). The urinary fluoride level was a significant predictor for intelligence (P 0.000).Conclusion:Children in endemic areas of fluorosis are at risk for impaired development of intelligence.

Study of thyroid hormones free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) in subjects with dental fluorosis

Apart from its well-known deleterious dental and skeletal effects, fluoride excess can have toxic effects on many other tissues. Fluoride, when in excess, is known to interfere with thyroid gland function. Fluoride-induced thyroid disturbances similar to those observed in iodine deficiency state in spite of adequate iodine intake have been documented. Similar thyroid disturbances in individuals with dental fluorosis have not been well studied in populations with endemic fluorosis. This work was undertaken to study the effects of fluoride-induced thyroid disturbances in individuals with dental fluorosis. The study group included 65 subjects with dental fluorosis from endemic fluorosis populations. An additional control group was comprised of 10 subjects without dental fluorosis. The drinking water fluoride levels of the study populations were analyzed. Serum free FT3, FT4, and TSH levels of both groups were assessed. All subjects with dental fluorosis had serum levels of thyroid hormones (FT3, FT4, and TSH) within the normal range, with the exception of 1 individual, who had elevated levels of TSH. Statistical significance was found when FT3 and TSH values were compared with different Dean's index groups by a 1-way ANOVA test: FT3 (F = 3.4572; P=.0377) and TSH (F = 3.2649 and P=.0449). Findings of this study did not show any significant alterations in the levels of the thyroid hormones FT3, FT4, and TSH in subjects with dental fluorosis. Our observations suggest that thyroid hormone levels were not altered in subjects with dental fluorosis. Hence, future studies of this kind, along with more detailed investigations are needed.

Prevalence of fluorosis in an endemic village in central India

Endemic fluorosis is an important public health problem in certain parts of the Durg district of Chhattisgarh. The aim of the study was to find out the prevalence of dental and skeletal fluorosis among the population and to assess the relation between drinking water fluoride level and prevalence of fluorosis. A cross-sectional survey was undertaken in Gureda Village, of the Durg district of Chhattisgarh state in October 2009. The survey covered 805 individuals - 362 males and 443 females. The prevalence of dental and skeletal fluorosis was assessed based on clinical examinations of individuals. Drinking and eating habits of individuals were recorded as per checklist. Water fluoride levels of prime water sources were also determined by lab examination. The prevalence of dental fluorosis was 8.2%. Both skeletal and dental fluorosis were more common in males. Dental fluorosis was higher in the 8-45 age group, whereas the prevalence of skeletal fluorosis increased with age. Genu varum (38.1%) and genu vulgum (6.3%) were the common skeletal deformities. Water fluoride levels ranged from 0.2 to 7.8 ppm.

The Relationships between Two Different Drinking Water Fluoride Levels, Dental Fluorosis and Bone Mineral Density of Children

This field study included the whole population of children aged 10–15 years (77 from a 0.19 mg/L F area; 89 from a 3.00 mg/L F area), with similar nutritional, dietary habits and similar ethnic and socioeconomic status. The fluoride concentration in the drinking water, the bone mineral content, the bone density and the degree of dental fluorosis were determined. The left radius was measured for bone width, bone mineral content, and bone mineral density. The mean fluorosis score was 1.3 in the low fluoride area and 3,6 in the high fluoride area. More than half the children in the low fluoride area had no fluorosis (scores 0 and 1) while only 5% in the high fluoride area had none. Severe fluorosis (30%) was only observed in the high fluoride area. The Wilcoxon Rank Sum Test indicated that fluorosis levels differed significantly (p < 0.05) between the two areas. No relationships were found between dental fluorosis and bone width or between fluorosis and bone mineral density in the two areas (Spearment Rank correlations). A significant increase in bone width was found with age but no differences amongst and boys and girls. A significant positive correlation was found in the high fluoride area between bone mineral density over age. In the 12-13 and 13-14 year age groups in the high fluoride area, girls had higher bone mineral densities. However, a significant negative correlation (p<0.02) was found for the low fluoride area (0.19 mg/L F) over age.

Diagnosis on endemic skeletal fluorosis: clinical vs. X-rays examination

Objective To compare the diagnosis results of endemic skeletal fluorosis from clinical and X-rays examinations, in order to provide the foundation for revising clinical diagnostic standard of endemic skeletal fluorosis. Methods The 675 inhabitants aged 16 to 60 years old were retrospectively chosen as subjects in 15 villages drinking un-improved water, where they lived for 10 years or more. Drinking water fluoride were rated as 0.5,1.0, 1.5,2.0,2.2,2.4,3.0,3.5,4.0,6.0,7.0 mg/L levels in Qianan and Nongan County of Jilin Province. The clinical and X-rays results of endemic skeletal fluorosis were analyzed and compared at different drinking water fluoride levels. Results The clinically detectable rates of endemic skeletal fluorosis(21.43%,22.45% ,21.28%, 19.05%, 38.89%) were higher than that of X-rays(0,2.04%,0,4.76%, 12.96%, X2=7.96,9.49,11.19,4.08,9.45, P 0.05). Conclusions The detectable rates of skeletal fluorosis increase with the increased concentration of water fluoride, which is more reliable for clinical examination than for X-rays method. Key words: Osteofluorosis; X-rays; Diagnosis; Drinking; Outcome assessment

Dose–effect relationship between drinking water fluoride levels and damage to liver and kidney functions in children

Although a dose–effect relationship between water fluoride levels and damage to liver and kidney functions in animals has been reported, it was not demonstrated in humans. To evaluate the effects of drinking water fluoride levels on the liver and kidney functions in children with and without dental fluorosis, we identified 210 children who were divided into seven groups with 30 each based on different drinking water fluoride levels in the same residential area. We found that the fluoride levels in serum and urine of these children increased as the levels of drinking water fluoride increased. There were no significant differences in the levels of total protein (TP), albumin (ALB), aspartate transamine (AST), and alanine transamine (ALT) in serum among these groups. However, the activities of serum lactic dehydrogenase (LDH), urine N-acetyl- β-glucosaminidase (NAG), and urine γ-glutamyl transpeptidase ( γ-GT) in children with dental fluorosis and having water fluoride of 2.15–2.96 mg/L and in children having water fluoride of 3.15–5.69 mg/L regardless of dental fluorosis were significantly higher than children exposed to water fluoride of 0.61–0.87 mg/L in a dose–response manner. In contrast to children with dental fluorosis and having water fluoride of 2.15–2.96 and 3.10–5.69 mg/L, serum LDH activity of children without dental fluorosis but exposed to the same levels of water fluoride as those with dental fluorosis were also markedly lower, but the activities of NAG and γ-GT in their urine were not. Therefore, our results suggest that drinking water fluoride levels over 2.0 mg/L can cause damage to liver and kidney functions in children and that the dental fluorosis was independent of damage to the liver but not the kidney. Further studies on the mechanisms and significance underlying damage to the liver without dental fluorosis in the exposed children are warranted.

Elevated Serum Fluoride Concentrations in Women Are Not Related to Fractures and Bone Mineral Density

Epidemiologic studies of the relations between drinking-water fluoride levels and bone mineral density (BMD) and fracture are characterized by disparate conclusions and an absence of information about individual circulating fluoride levels. This study relates serum fluoride concentrations, which reflect individual fluoride exposures, to BMD and bone fractures. Data are from 1300 female residents of 3 small communities in which the water fluoride concentrations were 52.6 or 210.4 micromol/L. Circulating serum fluoride concentrations were assessed by ion-specific electrode. Fluoride intake was estimated from interviews describing water and water-based beverage consumption and duration of residence in the community. BMD was measured by dual-energy X-ray densitometry and single-photon densitometry. Self-reported fractures were confirmed by medical record abstraction. The mean serum fluoride concentration in the high-fluoride community, 2.11 +/- 0.05 micromol/L, was significantly higher than serum fluoride concentrations in the control and high-calcium communities with water fluoridation to 52.6 micromol/L. The mean serum fluoride concentrations in these latter 2 communities were 1.6 +/- 0.04 and 1.22 +/- 0.05 micromol/L, respectively. Serum fluoride was not significantly related to BMD after adjusting for covariates including age and body size. The mean distal radius BMD, however, was significantly higher in the high-fluoride community. Serum fluoride concentrations were not related to incident osteoporotic fractures with 4 y of observation. Serum fluoride concentrations were not associated with BMD or osteoporotic fractures among female residents of communities with water fluoride concentrations of 52.6 or 210.4 micromol/L.

Ingestión y excreción de fluoruros en niños de Hermosillo, Sonora, México

To estimate the fluoride intake and urinary excretion among 8-9 year-old school children.A cross-sectional study was conducted from February to November 1997. Study subjects were 31 male children from Hermosillo, Mexico, living in three neighborhoods with different drinking water fluoride levels. Fluoride intake was measured through water intake and collection of food samples ingested in 24 hr. Fluoride excretion was measured in 24-hour urine samples. The fluoride concentration was measured by the potentiometer method using a fluoride-specific ion electrode.Statistically significant differences of fluoride levels in drinking water were found in the 3 different neighborhoods: 2.77, 0.78 and 0.54 mg/L, respectively (p < 0.01). The daily mean intake of fluoride for the neighborhood with the highest fluoride level was 5.41 mg/d, while mean intakes for the other two neighborhoods were 2.31 and 1.51 mg/d, respectively. Thirty-two percent of the children had fluoride intake above the recommendation values for this age group; sixty per cent of these children lived in the neighborhood with the highest fluoride level. Drinking water accounted for 63% of total fluoride intake, and the mean water intake was 1.8 liters. The mean excretion of fluoride was 1.61 mg/24 hours (range 0.18 to 8.1 mg/24 hr). Stepwise multiple regression showed an association between drinking water fluoride and fluoride urinary excretion (R2 = 0.56 p < 0.001).Fluoride intake in the neighborhood with the highest fluoride level was twice the daily recommended value for 8-9 year-old children. Drinking water was the main source of fluoride intake. The English version of this paper is available at: http://www.insp.mx/salud/index.html.