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Drinking water contamination
Published in Nick F. Gray, Water Science and Technology: An Introduction, 2017
Excess fluoride causes teeth to become discoloured (fluorosis) and long-term exposure results in permanent grey to black discoloration of the enamel (Section 19.1.5). Children who drink fluoride in excess of 5 mg L−1 also develop severe pitting of the enamel. With the increasing exposure of children to fluoride, the advantages of water fluoridation may be outweighed by the risk of fluorosis from overexposure (Figure 19.4). Fluoride is cumulative and so any long-term effects of low-dose exposure may well not be realized yet. Leaks and spillages of fluoride can be very serious and even fatal. The general effect of moderately elevated fluoride (30–50 mg L−1) will be mild gastroenteritis and possible skin irritation. For these reasons, many water suppliers have taken the precautionary step of not fluoridating water until more research has been done on the potential long-term health risks.
Chemical Drinking Water Parameters
Published in Frank R. Spellman, The Drinking Water Handbook, 2017
Water fluoridation prevents tooth decay primarily through frequent, daily contact with low levels of fluoride (CDC, 2011). Even today, with other available sources of fluoride, studies show that water fluoridation reduces tooth decay by about 25% over a person’s lifetime; in fact, drinking water containing a proper amount of fluoride can reduce tooth decay as much as 65% in children between the ages 12 and 15. It should be pointed out, however, that water fluoridation is not necessarily the safe public health measure we have been led to believe it is (Mullenix, 1997). Concerns about uncontrolled dosage, accumulation in the body over time, and effects beyond the teeth (brain as well as bones) have not been resolved, although most authorities believe that a moderate amount of fluoride ions (F–) in drinking water contributes to good dental health. Fluoride is seldom found in appreciable quantities of surface waters and appears in groundwater in only a few geographical regions, although it is sometimes found in a few types of igneous or sedimentary rocks. Fluoride is toxic to humans in large quantities (the key words here being “large quantities”) and is also toxic to some animals. Few would argue that small concentrations of fluoride (about 1.0 mg/L in drinking water) can be beneficial; however, when the concentration of fluoride in untreated natural water supplies is excessive, either alternativeDID YOU KNOW? Many communities choose to adjust the fluoride concentration in the water supply to a level beneficial to reduce tooth decay and promote good oral health. This practice is known as community water fluoridation. Given the dramatic decline in tooth decay over the past 60 years, the Centers for Disease Control and Prevention (CDC) named water fluoridation one of the ten great public health interventions of the 20th century (CDC, 2011).
Health risk assessment of fluoride in water distribution network of Mashhad, Iran
Published in Human and Ecological Risk Assessment: An International Journal, 2019
Mansour Ghaderpoori, Maryam Paydar, Ahmad Zarei, Hossein Alidadi, Ali Asghar Najafpoor, Abdol Hamid Gohary, Mahmoud Shams
In this study, levels of fluoride were lower than WHO guidelines which necessitate the implementation of precautionary options including water fluoridation to avoid dental cavities and other health problems. A regular monitoring schedule and health education should be given in regions where drinking water has high levels of fluoride contamination. Drinking water also required to be frequently tested to guarantee that the water being supplied for inhabitants meets the drinking water guidelines. This study presents preliminary information to the health professionals and the consumers regarding health risk assessments of fluoride in distribution network of Mashhad city, which can be applied for future drinking water quality monitoring and planning elsewhere.