Eight cities and towns in Massachusetts have had to stop adding sodium fluoride to their municipal water supplies after running out of the compound, which is used to prevent tooth decay. Health officials say some of the suspensions have been intermittent, but state data shows they have impacted roughly 250,000 residents over the last year in Fall River, Holden, Medway, Natick, North Attleboro, Rutland, Shrewsbury and Swansea.
While short-term pauses in water fluoridation are unlikely to impact oral health, longer-term disruptions can be a concern, dentists say, especially for children.
Shortages in fluoride supply are being felt in multiple states. The Massachusetts Department of Public Health declined interview requests, but a spokesman said the Association of State and Territorial Dental Directors and the federal Centers for Disease Control and Prevention have indicated the shortage is largely the result of transportation bottlenecks. The fluoride additive comes from overseas, often from China.
The U.S. Public Health Service recommends adding a small amount of fluoride to drinking water to help prevent cavities. Fluoride, a naturally occurring mineral, has been shown to strengthen tooth enamel. Its use is endorsed by major medical and dental organizations as a safe and cost-effective way to improve oral health.
"If it goes beyond three months, those kids are going to have less fluoride in their teeth and have less protection.”Myron Allukian, Jr., former dental director for Boston
There is little research on how long people can go without fluoridated water before it begins to impact their teeth. “There are no studies that I know,” said John Fisher, a dentist in Salem and past president of the Massachusetts Dental Society. He has traveled the state advocating for community water fluoridation.
Fisher said there are a few places, including in Canada, that have stopped fluoridating their water and, thus, there is some anecdotal evidence.
“After a year you'll start to see breakdown of the enamel such that, if you didn't know that the fluoride had been taken out, you'd start wondering what the problem is,” said Fisher, adding that dentists report significant dental changes after three years.
Myron Allukian, Jr., a dentist who served as Boston's dental director for over 30 years, said he’d start to worry even sooner.
“If it's a couple of weeks or a month or two, not a big deal. But if it goes beyond three months, those kids are going to have less fluoride in their teeth and have less protection,” Allukian said. He recommended that cities and towns impacted by shortages should notify local dentists.
Many of the water systems in Massachusetts that suspended fluoridation programs have notified customers through public notices and messages on their web sites and social media. WBUR contacted each of the eight cities and towns, but only got a response from Rutland — which hasn't had fluoride for six months.
Officials there said they were recently able to place an order, and they hope to resume fluoridating their water next week.
"I'm glad to have it back," said Joseph Buckley, director of public works for Rutland.
It is unclear how long fluoridation programs in other cities and towns have been paused.
Since supplies became constrained late last year, some municipal water systems have turned to nearby communities to borrow sodium fluoride, according to the Massachusetts Water Works Association, which lobbies on behalf of water professionals.
“We are fortunate that the water sector in Massachusetts is very collaborative and neighboring systems who might have stocks of fluoride have been able to loan some to their neighbor,” said Jennifer Pederson, the group's executive director.
Natick — which has been experiencing a shortage since January — has received the additive from Wellesley and elsewhere. Natick’s Water and Sewer Division did not respond to requests for comment for this story.
Not all municipal water systems in Massachusetts add fluoride, and some groups have opposed fluoridation programs arguing that scientists don't fully understand the health effects, and that individuals should be able to decide how much fluoride they get and where they get it from.
In places that don't add fluoride to drinking water — or where water fluoridation has been paused — residents can take supplements and use topical treatments. Meredith Bailey, president of the Massachusetts Dental Society, recommended conducting risk assessments for children in these areas. "Additionally, fluoride varnish should be offered to moderate and high-risk children by a dentist or physician at least twice a year," Bailey said.