Safety l Fluoridation Facts 65 Examination Surveys (NHANES) from 1976-1980 to 2003-2008 show that the percentage of children aged 1- to 5-years-old having high lead blood levels (≥10 μg/dL) declined dramatically from 88.2% to 0.9%.152 During that same time period (1976 to 2008), the percentage of the U.S. population receiving fluoridated water rose from approximately 48.8% to 64.3%.153 Moreover, in the 1991-1994 NHANES, the overall (all age groups) prevalence of high lead blood levels (≥10 μg/dL) was 2.2% but decreased to 0.7% by the 1999-2002 survey.151 While antifluoridationists claim that fluoridated water increases lead blood levels in children, the fact is that since 1976 while the use of water fluoridation has increased, the percentage of children in the U.S. with high lead blood levels actually has continued to decreased substantially. This demonstrates that the claim made by those opposed to water fluoridation that fluoride in water increases lead concentrations in children is unfounded. It should be noted that approximately 95% of the primary sources of adult lead exposure are occupational.154 In general, adult blood lead levels have continued to decline over recent decades due largely to improved prevention measures in the workplace and changes in employment patterns.154 Those opposed to water fluoridation sometimes claim that there is an increase in acidity when fluoride is added to water and that the acidic water in the system leaches lead from pipes and fixtures. The process of adding fluoride to water has minimal impact on the acidity or pH of drinking water. Under some water quality conditions, a small increase in the acidity of drinking water that is already slightly acidic can be observed after treatment with alum, chlorine, fluorosilicic acid or sodium fluorosilicate. In such cases, additional water treatment to adjust the pH to neutralize the acid in water distribution systems is standard practice in water plants.155 Water facilities typically maintain a pH of between 7.0 and 8.0 as standard practice indicating that the water leaving the plant is slightly alkaline and non-acidic.156 Despite this information, antifluoridationists continue to exploit their unfounded claims that fluoridation can lead to an increased uptake of lead by children. A 1999 study157 charged that fluorosilicic acid and sodium silicofluoride did not disassociate completely when added to water systems and could be responsible for lower pH (more acidic) levels of drinking water, leaching lead from plumbing systems and increasing lead uptake by children. In response to the study, scientists from the EPA reviewed the basic science that was the foundation for the claim that silicofluorides leach lead from water pipes and found that many of the chemical assumptions made in the original ecological study were scientifically unjustified.158 Fluoride additives do disassociate very quickly and completely release fluoride ions into the water. The research from the 1999 study was inconsistent with accepted scientific knowledge and the authors of that study failed to identify or account for those inconsistencies. The EPA scientists discounted the 1999 study and said there were no credible data to suggest any link between fluoridation and lead. Overall, the EPA scientists concluded that “…no credible evidence exists to show that water fluoridation has any quantifiable effects on the solubility, bioavailability, bioaccumulation, or reactivity of lead compounds.”158 43. Does drinking water fluoridated at recommended levels cause Alzheimer’s disease? Answer. The best available scientific evidence has not indicated an association between drinking optimally fluoridated water and Alzheimer’s disease. Fact. Scientists believe the causes of late-onset Alzheimer’s, the most common form of the disease, include a combination of age-related brain changes, genetic, lifestyle, and environmental factors. The importance of any one of these factors in increasing or decreasing the risk of developing Alzheimer’s could differ from person to person. Early-onset Alzheimer’s is less common (fewer than 10% of Alzheimer’s cases) with the first signs of the disease typically appearing between an individual’s 30s and mid-60s. It is believed to be caused primarily by gene changes passed down from parent to child.159 A study published in 1998160 raised concerns about the potential relationship between fluoride, aluminum and Alzheimer’s disease. However, several flaws in the study’s experimental design precluded any definitive conclusions from being drawn.161 Concerns were noted about a number of aspects of the protocol including, but not limited to, the high percentage of the test rodents dying during the study and that
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