Fluoride, a compound that prevents tooth decay, has not been added to Evansville’s drinking water supply since February.
That’s when American Water Enterprises, the company that operates the city’s water treatment plant, ran out of the compound.
The company has not been able to get more.
Evansville is not alone in having unfluoridated water. A shortage of the compound, most often created as a byproduct of phosphate mining, has been reported in cities in New York, Florida, Washington and throughout the Midwest.
Mary Armacost, water quality manager for American Water Enterprises at Evansville, said the State Board of Health had attributed the shortage to damage of Gulf Coast manufacturing facilities by Hurricane Katrina nearly two years ago.
Others attribute the shortage to a downturn in the phosphate mining industry, particularly in Florida.
“Everyone is facing the same problem,” she said, adding that supplies had been on order since last November. The company has checked with numerous vendors, she said, but all have been affected by the shortage. Providers no longer give an estimate of when supplies will return to normal, Armacost said.
The Evansville plant uses a little less than 300 pounds of fluoride each day to bring the compound to the level of 1 milligram per liter, she said.
Fluoride is not required in drinking water, Armacost said, but “it’s something that’s expected.” American Water Enterprises had notified the Indiana State Board of Health of its absence, she said.
The addition of fluoride to drinking water supplies has been credited with a sharp drop in dental cavities, but local dentists say its absence would have to be long-term to have a severe impact.
“I’m not really concerned because it’s going to be short term,” said Dr. Mark Schymik of Tri-State Family Dental Center. “Immediately, it’s not going to have an impact, but long term, depending on how long these (manufacturing) facilities are out of business, what you’d notice is an increase in dental disease, i.e., cavities if this went on for an extended period of time,” said Dr. Barry Ray, former president of the Evansville Dental Association.
He also noted that fluoride is naturally occurring in groundwater, and he expects some level was present in water drawn from the Ohio River.
“Indiana University headed up a study back in the ’50s to show the beneficial effect of fluoride in the water system, and consequently, we’ve closed down about seven dental schools in the last 15 years directly related to fluoride in the water,” Ray said.
The dentists said fluoride is most important during children’s developing years. “Fluoride gets in a person’s system, and it replaces calcium right after childbirth when a child starts drinking water,” Ray said. “If we were without (fluoride) for probably three years, a child just now born, you’d have to suspect and logic would dictate that child’s teeth would not be as resistant to decay.”