SEVERE WX : Red Flag Warning - Air Quality Alert View Alerts

FDA proposes new fluoride standard for bottled water, but some say it's still too high

The US Food and Drug Administration is proposing a lower concentration level standard for fluoride in bottled water, yet some scientists and environmental gr...

Posted: Apr 3, 2019 3:47 AM
Updated: Apr 3, 2019 4:08 AM

The US Food and Drug Administration is proposing a lower concentration level standard for fluoride in bottled water, yet some scientists and environmental groups believe that the proposed limit is still too high and poses a danger to human health.

If finalized, the new regulation would lower allowable levels of fluoride in domestically packaged and imported bottled water to 0.7 milligrams per liter, a slight reduction from the current standard of 0.8 milligrams per liter allowed by the FDA.

The proposed standard would apply only to bottled water with added fluoride. It would not affect allowable levels of fluoride in bottled water that may contain fluoride from source water.

Dental health

The FDA's proposed rule aligns with a 2015 recommendation from the US Public Health Service, part of the US Department of Health and Human Services, that suggests 0.7 milligrams per liter is the optimal fluoride concentration for community water systems that add fluoride.

The new rule "is based on findings from evolving research on optimal concentrations of fluoride that balances fluoride's benefits in preventing tooth decay with its risk of causing dental fluorosis, a condition most often characterized by white patches on teeth," the FDA said in its statement. Dental fluorosis is caused by taking in too much fluoride over a long period when adult teeth are forming under the gums.

But some scientists' concerns extend far beyond fluorosis.

"Given that fluoride can damage brain development, I would recommend that the maximum fluoride concentration in bottled water be kept at a lower level than 0.7 mg/L," Dr. Philippe Grandjean, an adjunct professor of environmental health at the Harvard TH Chan School of Public Health, wrote in an email.

Christopher Neurath, research director of the American Environmental Health Studies Project, which is connected to the Flouride Action Network, an environmental advocacy group, said "currently, there are rapidly increasing scientific studies showing neurotoxicity to fluoride," with research showing a direct link between children's IQ and their level of fluoride exposure in the womb: "That is our largest concern."

Behavioral and cognitive health effects

Morteza Bashash, an assistant professor in the Dalla Lana School of Public Health at the University of Toronto, found higher fluoride levels as measured in urine samples of pregnant women are associated with both lower IQ and increased risk of ADHD among children in Mexico.

Specifically, Bashash found a drop in childrens' scores on intelligence tests for every 0.5 milligram-per-liter increase in fluoride exposure beyond 0.8 milligrams per liter detected in a pregnant mother's urine. It is not clear whether this is research applicable to the US population, he told CNN.

In Mexico, for example, the government delivers cavity-reducing fluoride by adding it to salt, not water (since many people avoid drinking tap water).

Still, his research findings were "based on the true measurement of fluoride absorbed in the body." And a Canadian study presented at a conference last year and studies conducted in China showed IQ losses as related to fluoride levels within a similar order of magnitude.

Due to similar fluoride sources, regulations and diet, Canada's findings of urine levels are likely similar to American urine levels, said Bashash.

Neurath trusts that both the Mexican and Canadian study results would generally apply to the US since "urine fluoride is best measure of total fluoride intake."

Canadian data from the past 15 years has shown that women living in cities with fluorinated water supplies had "almost double" urine fluoride concentrations levels as women living in non-fluorinated cities. "Drinking water fluoride is the major source of fluoride for these women," he said.

The effect of prenatal exposure to fluoride on IQ are "very large," Neurath believes. "And on a population basis, that's very concerning."

Proposed rule may not be adequate

Neurath himself published a study of dental fluorosis this year, based on National Health and Nutrition Examination Survey data, that found a "dramatic increase in fluorosis" over results from a decade ago. (The study, though published in a peer-reviewed journal, is co-authored by an attorney representing the Fluoride Action Network in legal action regarding regulation of fluoridation chemicals by the US Environmental Protection Agency.)

More than 30% of adolescents in the study showed moderate to severe dental fluorosis (an additional 35% of children showed lesser signs of the condition), "a huge increase" over a survey conducted about a decade prior, Neurath said. He believes that the proposed standard is unlikely to reduce dental fluorosis to acceptable levels.

However, he has a bigger concern. "Dental fluorosis is a visible sign of overexposure to fluoride, but there are other nonvisible signs and adverse health effects that are much more serious," Neurath said based on the work of Bashash and Grandjean.

Grandjean's work, which was funded by the National Institute of Environmental Health Sciences. "Our review of studies from China and our own field study is in accordance with a recent study by US researchers carried out in Mexico that elevated exposure to fluoride during pregnancy is associated with toxicity to brain development.

"Given that fluoride is added to toothpaste to secure that the enamel surface of the teeth is properly protected against caries, there is no need to supplement the dietary fluoride intake," he said.

Alternatively, Bashash said fluoride in drinking water is considered one of the "biggest public health victories" in preventing cavities. While his job as a scientist is to study a given topic, It is the job of policymakers to come up with the overall understanding of what's necessary. The FDA looks "at the big picture" by gathering the evidence and evaluating the pros and cons based on national priorities. "This has been a hot topic for 60 years."

Linda Birnbaum, director of the National Institute of Environmental Health Sciences, explained that a "large, cross-government working group" looked at the data available in 2010 to 2011 and concluded that 0.7 mg/L was the appropriate level of fluoride concentration in drinking water, one that "balances protection from dental caries while limiting the risk from dental fluorosis."

The institute has funded studies that explore other health effects, she said, "and we are looking at the information in a systematic review now."

The International Bottled Water Association, a trade group, said it supports the FDA proposal to revise the standard of quality for fluoride added to bottled water.

"Most companies are well below" the newly proposed limit, according to Jill Culora, a spokeswoman for the association. "The proposed rule takes into account the many sources of fluoride in people's diets and will further reduce the risk of dental fluorosis, while still providing an optimal level of fluoride to help prevent tooth decay."

Cavities are not the only concern, said Neurath: "The proposed rule is not adequate."

Oregon Coronavirus Cases

Data is updated nightly.

Cases: 224547

Reported Deaths: 2877
CountyCasesDeaths
Multnomah42425618
Washington28176259
Marion24842333
Clackamas20349243
Lane15401176
Jackson13240160
Deschutes1074187
Umatilla988394
Linn644882
Yamhill515882
Klamath498279
Douglas479594
Polk440457
Josephine438076
Malheur370967
Benton354822
Jefferson252842
Coos241040
Columbia213732
Union175924
Wasco160631
Lincoln159122
Crook144724
Hood River128934
Morrow125017
Clatsop123711
Baker116018
Curry86512
Tillamook7985
Grant5657
Lake4868
Harney46611
Wallowa2486
Gilliam881
Sherman872
Wheeler491
Unassigned00

California Coronavirus Cases

Data is updated nightly.

Cases: 4003787

Reported Deaths: 64620
CountyCasesDeaths
Los Angeles131165624721
Riverside3112424667
San Bernardino3095025265
San Diego3011003805
Orange2856205146
Santa Clara1245862183
Sacramento1178311790
Kern1143421428
Fresno1057321746
Alameda980131290
Ventura845891046
Contra Costa78084836
San Joaquin776151461
Stanislaus666191097
Tulare50731854
San Mateo45255588
Monterey44651528
San Francisco41758565
Solano36525261
Santa Barbara36106469
Sonoma33414331
Merced33321485
Imperial29333746
Placer25624307
Kings23790251
San Luis Obispo22356267
Madera17220249
Santa Cruz16779207
Yolo15149215
Marin15039243
Butte13523205
Shasta13179242
El Dorado11312121
Napa1055282
Sutter10343127
Yuba712950
San Benito632664
Tehama592766
Lassen590526
Nevada568575
Humboldt535154
Mendocino485652
Tuolumne469173
Lake440866
Amador395348
Siskiyou259640
Glenn248127
Colusa238118
Calaveras235658
Del Norte174710
Inyo148238
Mono13395
Plumas7926
Modoc5767
Mariposa5377
Trinity4696
Sierra1370
Alpine910
Unassigned810
Medford
Partly Cloudy
67° wxIcon
Hi: 84° Lo: 59°
Feels Like: 67°
Brookings
Partly Cloudy
52° wxIcon
Hi: 76° Lo: 54°
Feels Like: 52°
Crater Lake
Clear
67° wxIcon
Hi: 64° Lo: 52°
Feels Like: 67°
Grants Pass
Partly Cloudy
67° wxIcon
Hi: 83° Lo: 62°
Feels Like: 67°
Klamath Falls
Partly Cloudy
50° wxIcon
Hi: 74° Lo: 53°
Feels Like: 50°
Smoky skies and spotty Thursday thunderstorms
KDRV Radar
KDRV Fire Danger
KDRV Weather Cam

Community Events