Residents of Portland, Ore., embrace the city's famously liberal vibe, but is that hurting some of the region's low-income children? Portland is the last major city in U.S. that does not add fluoride to its drinking water, and some say that has worsened the dental health of its citizens, especially young kids from lower-income families.


Portland has been debating fluoride for decades, but that debate is coming to a head this week as the city council is due to vote on a new fluoridation plan on Sept. 12. The plan has been pushed by Portland Mayor Sam Adams and endorsed by Oregon Gov. John Kitzhaber. If approved, the plan would affect not only the city of Portland but also the nearly one-quarter of the state that gets its water from the Bull Run Watershed.


But not everyone agrees. At a well-attended public hearing on Sept. 6, resident Angel Lambert argued "If there's a problem with kids' dental health, why don't we put the money toward better nutrition?" Others are vocal about the potential health impacts of fluoride, saying it can affect brain development and cause thyroid and kidney issues.


City Commissioner Nick Fish downplayed those worries. "Over the last 50 years, as we have fluoridated more water, the overall IQ of Americans has gone up," he told Bloomberg News. "I don't suggest a cause-and-effect, but I also think it shows the reverse isn't true."


Adams told the New York Times that adding fluoride to Portland's water is about health equality and social justice. "I hope that folks, whether they agree with me or not, understand that my intentions are to help those Portlanders that have no voice in this process."


No matter which way the vote goes, Portland and the surrounding community need to improve when it comes to dental health. According to Bloomberg News, the state's Department of Human Services found in 2007 that 35 percent of Oregon's children in first, second and third grade had untreated tooth decay. The percentage in nearby Idaho, where fluoridation rates are higher, is 27 percent. In Washington state, it's just 19 percent.


According to the U.S. Centers for Disease Control and Prevention, community water fluoridation is one of the 10 great public health achievements of the 20th century. The water from Bull Run does contain some natural fluoride, but it is well below the amount that would fight cavities, a fact spelled out on the website of the Portland Water Bureau. The website cautions customers, "You may want to consult with your dentist about fluoride treatment to help prevent tooth decay, especially for young children."


The city council is due to vote on Sept. 12. If approved, the city's water will be fluoridated by March 2014. The expected cost of the project is $5 million.


Related dental health story on MNN: What's in toothpaste?


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