Fluoride intake and urinary excretion in 6- to 7-year-old children living in optimally, sub-optimally and non-fluoridated areas.
ABSTRACT This study was designed to measure total intake, urinary excretion and estimated retention of fluoride in children under customary fluoride intake conditions, living in either fluoridated or low-fluoride areas of north-east England. Subsidiary aims were to investigate the relationships between the variables measured.
Using a randomized cluster design with schools as the sampling units, four schools from a non-fluoridated area and two from a fluoridated area were selected from the schools chosen to participate in the study. Fluoride intake from diet and toothbrushing was assessed using a 3-day food diary and fluoride analysis of expectorated saliva during toothbrushing. Samples of all foods and drinks consumed were measured for fluoride content using direct and indirect silicon-facilitated diffusion methods as appropriate. Urinary fluoride excretion and urine volume were measured over 24 h and estimation of fractional urinary fluoride excretion (FUFE) and fluoride retention made from collected data. Following descriptive analysis of variables, Pearson's correlations investigated relationships between fluoride content of home tap water, daily fluoride intake, excretion and retention.
Thirty-three children completed the study: 18 receiving non-fluoridated water [mean = 0.08 (+/-0.03) mg F/l], nine sub-optimally fluoridated water [mean = 0.47 (+/-0.09) mg F/l] and six optimally fluoridated water [mean = 0.82 (+/-0.13) mg F/l] at the time of the study. Complete data on F intake, excretion and retention were available for 29 children. Mean fluoride intake from diet and toothpaste ranged from 0.031 (+/-0.025) mg/kg body weight (bw)/day for the low-fluoride area to 0.038 (+/-0.038) and 0.047(+/-0.008) mg/kg bw/day for sub-optimally and optimally fluoridated areas respectively. Contribution of toothpaste to total fluoride intake ranged from 3% to 93% with mean values of 57%, 35% and 47% for children receiving low, sub-optimally and optimally fluoridated water respectively. FUFE ranged from a mean of 32% (+/-13%) for the optimally fluoridated area to 44% (+/-33%) for the low-fluoride area. Fluoride retention was not correlated with the fluoride concentration of home water supply, but was strongly positively correlated (P < 0.001) with total daily fluoride intake.
In an industrialized country, total fluoride intake, urinary excretion and consequently fluoride retention no longer reflect residence in a community with a non-fluoridated or fluoridated water supply. Fluoride toothpaste contributes a significant proportion of total ingested fluoride in children, particularly in low-fluoride areas.
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ABSTRACT: Background Children in Gaza Strip suffer from a high prevalence of dental fluorosis.AimsTo estimate and compare total daily fluoride (F) intake (TDFI) and investigate the relative contributions of different sources of F to TDFI, in 3- to 4-year-old children in Gaza Strip, exposed to low (<0.7 mg/litre), moderate (0.7–1.2 mg/litre) or high (>1.2 mg/litre) F concentrations in tap water.DesignA 3-day food diary and samples of tap water, drinks, foods, toothpastes and toothbrushing expectorate were collected from 216 children receiving low (n = 81), moderate (n = 72) or high (n = 63) F concentrations in tap water. F concentration of samples was analysed using an F-ion-selective electrode. TDFI from all sources was estimated. Data were analysed by anova and Tukey's test.ResultsThe mean (±SD) F concentration in low, moderate and high F tap waters was 0.21(±0.15), 0.91(±0.13) and 1.71(±0.35) mg/litre, respectively. Mean (±SD) TDFI was 0.02(±0.01), 0.04(±0.01) and 0.05(±0.03) mg/kg bw/day, respectively (P < 0.0001). Foods made the largest contribution (63.9%) to TDFI.Conclusion Total daily fluoride (F) intake increased as F concentration in tap water increased. Foods were the primary source of F. Programmes for monitoring fluoride expose should consider the fluoride concentration of water used for food preparation and local dietary behaviours.International Journal of Paediatric Dentistry 04/2014; DOI:10.1111/ipd.12108 · 1.54 Impact Factor
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ABSTRACT: Used frequently in food contact materials, bisphenol A (BPA) has been studied extensively in recent years, and ubiquitous exposure in the general population has been demonstrated worldwide. Characterizing within- and between-individual variability of BPA concentrations is important for characterizing exposure in biomonitoring studies, and this has been investigated previously in adults, but not in children. The aim of this study was to characterize the short-term variability of BPA in spot urine samples in young children. Children aged ≥2-<4years (n=25) were recruited from an existing cohort in Queensland, Australia, and donated four spot urine samples each over a two day period. Samples were analysed for total BPA using isotope dilution online solid phase extraction-liquid chromatography-tandem mass spectrometry, and concentrations ranged from 0.53 to 74.5ng/ml, with geometric mean and standard deviation of 2.70ng/ml and 2.94ng/ml, respectively. Sex and time of sample collection were not significant predictors of BPA concentration. The between-individual variability was approximately equal to the within-individual variability (ICC=0.51), and this ICC is somewhat higher than previously reported literature values. This may be the result of physiological or behavioural differences between children and adults or of the relatively short exposure window assessed. Using a bootstrapping methodology, a single sample resulted in correct tertile classification approximately 70% of the time. This study suggests that single spot samples obtained from young children provide a reliable characterization of absolute and relative exposure over the short time window studied, but this may not hold true over longer timeframes.Environment international 04/2014; 68C:139-143. DOI:10.1016/j.envint.2014.03.027 · 6.25 Impact Factor
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ABSTRACT: PURPOSE: To determine the fluoride intake in three- to five-year-old preschool children from two communes in Chile, one with a non-fluoridated public water supply (Maipú) and the other with fluoridated public water supply since 1996, at a fluoride concentration of 0.6 mg/L (Peñalolen). METHODS: Cross-sectional, observational design. The sample population was composed of 200 three-to-five-year-old children attending four kindergartens in the Santiago Metropolitan Region, Chile, in the communes of Maipú and Peñalolen. Intake of fluoride was measured in a morning urine sample by using an ion-specific electrode and creatinine concentration. The fluoride intake from other sources was estimated from the parents' and educators' survey answers. RESULTS: The daily dose of fluoride intake (DDI) for all Maipú preschoolers was 0.021 mg F/kg body weight (bw)/day, a value less than the optimal dose, which is 0.05 to 0.07 mg F/kg bw/day. The DDI for the Peñalolen sample reached 0.066 mg F/kg bw/day. There is a contribution from fluoride toothpaste ingestion of 0.019 mg F/kg bw/day in Maipú and 0.017 mg F/kg bw/day in Peñalolen. The overall frequency of daily brushing was 3.15 times, during which 31% of Maipú children and 33% of Peñalolen children ingested toothpaste. The estimated amount of fluoride intake from toothpaste and tea consumption explained the contribution of fluoride not coming from fluoridated water. CONCLUSION: The fluoride ingestion from water and other sources in the preschool commune of Peñalolen is much higher than the fluoride intake in preschoolers of the Maipú district.12/2009; 25(3):239-244. DOI:10.1590/S1980-65232010000300004