Note: The article appears in the April 12, 2010, hard version of Time Magazine. It was available online on April 5.
What It Is: A form of the basic element fluorine
Found In: Toothpaste, tap water
Health Hazards: Neurotoxic and potentially tumorigenic if swallowed; the American Dental Association advises that children under 2 not use fluoride toothpaste
What You Should Know: Government studies support current fluoride levels in tap water, but studies on long-term exposure and cancers are ongoing
Chemicals in plastics and other products seem harmless, but mounting evidence links them to health problems — and Washington lacks the power to protect us