HEALTH

Portland Voters Reject Fluoridation, Again
For the fourth time since 1956, residents of Portland, Oregon, have rejected a measure to add fluoride to the city’s water supply. This leaves Portland as the largest urban area in the U.S. without fluoridated water.

Discussion Ideas:

• Portland is the largest city in the U.S. without fluoridated water.Why do students think most urban areas invest in fluoridating their water?
  • Most cities add minute amounts of fluoride to the community water supply as a public health policy. In fact, the U.S. Centers for Disease Control lists water fluoridation as one of the “Ten Great Public Health Achievements” of the last century. The American Dental Association says “water fluoridation is the single most effective public health measure to prevent tooth decay.”
    • Fluoride, an ion of the element fluorine, occurs naturally in water and food. Fluoridation is the adjustment of the existing, naturally occurring fluoride levels in drinking water to the fluoride level recommended by the U.S. Public Health Service for the prevention of tooth decay (0.7 – 1.2 parts per million).
    • Most fluoride treatments are topical, meaning they interact directly with the saliva and other precious bodily fluids to reduce the rate of tooth decay. Toothpastes, mouthwashes, and dental flosses often contain fluoride. More intense fluoride treatments are also administered by dentists and other oral health professionals.
• After reading the Oregonian article, why do students think Portland voters rejected the measure to fluoridate their water?
  • Those opposed to the measure rejected it for several reasons:
    • The science supporting fluoridation was questioned. Although nearly all science and public-health authorities support fluoridation, many voters simply did not accept the evidence. Can students think of other debates where people do not accept overwhelming scientific evidence?
      • anthropogenic global warming. Scientists agree that human activity is contributing to climate change, but the public does not.
      • round Earth. Most of the public agrees on this one these days, but there are a few hold-outs.
      • Bigfoot. Biologists have yet to find any accepted evidence of a large North American primate, but the search continues.
  • Voters worried about polluting Portland’s water supply. This opposition had several forms.
    • Opponents labeled fluoride a dangerous toxic substance, which it is in large doses.
    • Portland, part of the enormous Willamette and Columbia River watersheds, has some of the purest, safest drinking water in the nation. In fact, its water is not even filtered. (Portland’s water is treated with chlorine, ammonia, and sodium hydroxide, however. These chemicals disinfect the water and prevent it from corroding metal pipes and other plumbing fixtures.) Voters expressed concerns about adding excess chemicals to such a pure natural resource.
  • The initial $5 million start-up cost was considered expensive.
• Look through our extensive guide to “Earth’s Freshwater.” Chapter four, “Water Quality in Freshwater Systems,” includes a very short section on “Drinking-Water Treatment” on page 84. Read those paragraphs, which explain why communities treat drinking water with chemical additives (including fluoride). Do students know how their drinking water is treated? Do they know if their water is fluoridated?
  • Find out! Contact your local water company and discover how your drinking water is being treated. This EPA map will get you started.