National Research Council (2006)

An overview of the NRC's groundbreaking report on fluoride toxicity, including excerpts of its key findings and recommendations, statements from the panelists, and a discussion of its relevance to water fluoridation and sulfuryl fluoride.


On March 22, 2006, the prestigious National Research Council of the National Academies of Science released a 450-page review of fluoride toxicity. The report, which was three years in the making, concluded that the safe drinking water standard for fluoride (4 ppm) causes significant damage to teeth, and places consumers at elevated risk for bone damage, including bone fracture and joint pain. Because of this, the NRC recommended that the fluoride safety standard be reduced. In addition to its concerns about tooth and bone damage, the NRC identified a range of other health effects that may be associated with fluoride exposure, including damage to the brain, disruption of the endocrine system (thyroid gland, pineal gland, and glucose metabolism), and bone cancer.

While proponents of fluoridation have long claimed that the safety of fluoride is a “settled” question, the NRC report emphatically undermines this contention. The NRC report identifies a staggering number of fundamental questions about fluoride’s safety that have yet to be adequately addressed. According to the panel’s chairman Dr. John Doull, “when we looked at the studies that have been done, we found that many of these questions are unsettled and we have much less information than we should, considering how long this [fluoridation] has been going on. I think that’s why fluoridation is still being challenged so many years after it began.”

As noted by FAN’s Executive Director, Dr. Paul Connett, “the crucial message of this report is that the highest scientific authority in the US has determined that low levels of fluoride in drinking water may have serious adverse health effects.”


The NRC began working on the report in 2003 following a request by the US Environmental Protection Agency (EPA) to review the latest research on fluoride toxicity and assess the adequacy, or lack thereof, of EPA’s “Maximum Contaminant Level Goal” (MCLG). The MCLG is the maximum level of a water contaminant that EPA considers safe for all subsets of the population, including the most vulnerable. The MCLG for fluoride is currently 4 parts per million (ppm), or 4 milligrams of fluoride in each liter of water (mg/L). This standard was established in 1985 amidst considerable controversy. As noted in 1983 by Dr. Stanley Wallach, a member of a Surgeon General committee that advised EPA on fluoride’s non-dental health effects: “You would have to have rocks in your head, in my opinion, to allow your child much more than 2 ppm.” EPA’s decision to enact the 4 ppm MCLG was thus harshly criticized by the Natural Resources Defense Council (NRDC) and even EPA’s own scientists.