Dental caries and dental fluorosis according to water fluoridation among 12-year-old Brazilian schoolchildren: a nation-wide study comparing different municipalities

Feasibility of increasing calcium content of drinking tap water following quality regulations to improve calcium intake at population level

Background

Calcium intake is below recommendations in several parts of the world. Improving calcium intake has benefits not only for bone health but also helps to prevent pregnancy hypertension disorders. Calcium concentration of tap water is usually low The aim of the present study was to determine the maximum amount of calcium that can be added to tap water while complying with drinking water Argentine regulations.

Methods

Tap water samples were collected from the Province of Buenos Aires (Argentina). Physicochemical properties and saturation index were measured. Different incremental concentrations of calcium chloride were added to the experimental aliquots.

Results

Baseline water had a mean calcium concentration of 22.00 ± 2.54 mg/L, water hardness of 89.9 ± 6.4 mg/L CaCO 3, and a saturation index of -1.50 ± 0.11. After the addition of 0.4554 ± 0.0071 g of salt, water hard-ness reached 355.0 ± 7.1 mg/L CaCO 3, a calcium concentration of 140.50 ± 2.12 mg/L, and a saturation index -0.53 ± 0.02.

Conclusions

This study shows that at laboratory level it is feasible to increase calcium concentration of drinking water by adding calcium chloride while complying with national standards. Calcium concentration of drinking tap water could be evaluated and minimum calcium concentration of tap water regulated so as to improve calcium intake in populations with low calcium intake.

Human health risk assessment of metals and anions in surface water from a mineral coal region in Brazil

Coal mining releases high concentration elements to the environment, which can be deposited in surface water, causing several human health problems. Candiota mine in the south of Brazil is the largest coal reserves in the country, representing approximately 40% of total national coal reserves. Therefore, the present study aimed to estimate the chronic daily dose and the non-carcinogenic risk index for metals and anions in surface waters of Candiota Region, using the USEPA protocols for Human Health Risk Assessment. A total of eight water samples were collected over a distance of up to 15 km from the emission sources of the thermal power generation companies, then the Chronic Daily Intake (CDI), Hazard Quotient (HQ), Hazard Index (HI), and sum of Hazard Index (ΣHI) were calculated. All the elements and anions evaluated showed natural concentrations for continental fresh waters according to Brazilian legislation, except Pb. Individually, none of the metals Pb, As, Cd, Ni, and Se or anions F^- and NO₃^- showed an HI value greater than 1. However, the sum of HI (ΣHI) (five metals and two anions) by sample point showed values close to 1, for one of the eight points analyzed. Pb and Fe were the elements that most contribute to the risk values in the sample points of the study area. Although, there is no human health risk in this scenario, this investigation highlight priority elements to future investigations in coal mine areas. In the current region, Pb and F^- as priority elements for future studies.

Area-level deprivation, childhood dental ambulatory sensitive hospitalizations and community water fluoridation: evidence from New Zealand

Background

We examined the association between area-level deprivation and dental ambulatory sensitive hospitalizations (ASH) and considered the moderating effect of community water fluoridation (CWF). The hypothesis was that higher levels of deprivation are associated with higher dental ASH rates and that CWF will moderate this association such that children living in the most deprived areas have greater health gain from CWF.

Methods

Dental ASH conditions (dental caries and diseases of pulp/periapical tissues), age, gender and home address identifier (meshblock) were extracted from pooled cross-sectional data (Q3, 2011 to Q2, 2017) on children aged 0–4 and 5–12 years from the National Minimum Dataset, New Zealand (NZ) Ministry of Health. CWF was obtained for 2011 and 2016 from the NZ Institute of Environmental Science and Research. Dental ASH rates for children aged 0–4 and 5–12 years (/1000) were calculated for census area units (CAUs). Multilevel negative binomial models investigated associations between area-level deprivation, dental ASH rate and moderation by CWF status.

Results

Relative to CWF (2011 and 2016), no CWF (2011 and 2016) was associated with increased dental ASH rates in children aged 0–4 [incidence rate ratio (IRR) = 1.171 (95% confidence interval 1.064, 1.288)] and aged 5–12 years [IRR = 1.181 (1.084, 1.286)]. An interaction between area-level deprivation and CWF showed that the association between CWF and dental ASH rates was greatest within the most deprived quintile of children aged 0–4 years [IRR = 1.316 (1.052, 1.645)].

Conclusions

CWF was associated with a reduced dental ASH rate for children aged 0–4 and 5–12 years. Children living in the most deprived areas showed the greatest effect of CWF on dental ASH rates, indicating that the greater health gain from CWF occurred for those with the highest socio-economic disadvantage. Variation in CWF contributes to structural inequities in oral-health outcomes for children.

External control of water fluoridation in a small municipality of northeast of Brazil

Abstract Introduction Fluoridation of public water supply is an important measure in the prevention of dental caries. Objective This study aimed to monitor the fluoride (F) concentrations of a public water supply with water fluoridation program in a small municipality in the Northeast region of Brazil. Material and method It is a quantitative study with a descriptive approach. Three points of the urban area were selected for collecting water samples twice a month for 12 months. The average of F concentrations was calculated considering these three samples of each collection point at the same occasion. F concentrations in the water samples were determined by potentiometry and the results were classified according to the criterion proposed by criterion set down by Collaborating Center of the Brazilian Ministry of Health for Oral Health Surveillance. The samples were classified according to the best risk-benefit adjustment (0.55 – 0.84 mg F /L). Result Less than 10% of the samples were within the ideal range. Conclusion It was observed that water fluoridation in this municipality was interrupted since many water samples showed f-levels below the minimal acceptable values.

Calcium Intake and Health

There are striking inequities in calcium intake between rich and poor populations. Appropriate calcium intake has shown many health benefits, such as reduction of hypertensive disorders of pregnancy, lower blood pressure particularly among young people, prevention of osteoporosis and colorectal adenomas, lower cholesterol values, and lower blood pressure in the progeny of mothers taking sufficient calcium during pregnancy. Studies have refuted some calcium supplementation side effects like damage to the iron status, formation of renal stones and myocardial infarction in older people. Attention should be given to bone resorption in post-partum women after calcium supplementation withdrawal. Mechanisms linking low calcium intake and blood pressure are mediated by parathyroid hormone raise that increases intracellular calcium in vascular smooth muscle cells leading to vasoconstriction. At the population level, an increase of around 400-500 mg/day could reduce the differences in calcium intake between high- and middle-low-income countries. The fortification of food and water seems a possible strategy to reach this goal.