Part of the fallout from Hurricane Katrina was a disruption in Florida phosphate mining, a byproduct of which is the fluoride added to drinking water to prevent tooth decay.
Fluoride supplies were interrupted and costs went up, leading some cities — including Evansville — in several states to stop adding fluoride to water.
That’s not an option in Kentucky, which requires water fluoridation for most cities.
And even if the cost continues to rise, fluoride is a great value just for what it does for dental health, local and state health care providers say.
Water fluoridation reduces tooth decay by up to 40 percent, according to the Centers for Disease Control and Prevention
“The CDC says it’s one of the 10 greatest public health achievements in their history,” said Robert Murphy, health program administrator in the state Department for Public Health’s Office of Oral Health.
In 2001, the CDC said $38 is saved in dental treatment costs for every $1 spent on fluoridation.
“That’s a major cost savings,” said Deborah Fillman, community education director with the Green River District Health Department. “It looks to me like the return on the investment is so much more (than increased costs).”
The cost of fluoride went up 70 percent when Owensboro Municipal Utilities signed its new yearlong contract with its supplier in March, said Herman Cecil, water services director.
That meant paying about $15,000 more to Brenntag Mid-South Inc., which has an office in Henderson, for the 12,000 gallons of fluoride OMU uses annually, Cecil said.
“The shortage started showing up last summer,” Cecil said. “We knew there’d been problems with the fluoride supply.”
The increased cost by itself isn’t enough to warrant passing along to customers, but combined with other cost increases over time “that has an impact on water rates,” Cecil said.
Fluoride “is still a very good value for the money (a) water plant would be spending for the increase,” Murphy said. “The benefits far outweigh any of the cost increases.”
Having a cavity filled costs $65 to $75, not including the office visit and time needed to go there, said Dr. Robey Crowe, who has a dental practice on Goetz Drive.
Even if every consumer household had to pay an extra $2 a month, Crowe said, “It’d be well worth it.”
Fluoride strengthens a tooth’s enamel, which can be affected by the conversion of sugars into acids by the mouth’s naturally occurring bacteria, Crowe said.
When he started his practice here in 1972, Crowe said, the city had fluoridated water but most county residents got their water from wells.
City Head Start children he examined had few cavities, while their county counterparts had five or six each, he said.
When the county started getting city water, “we saw a big drop in the number of cavities,” Crowe said.
About 97 percent of Daviess County residents now get fluoridated drinking water, Murphy said.
Nearly all residents in Muhlenberg (94 percent), Hancock (89 percent) and Ohio and McLean (88 percent each) get treated water, he said.
Those who don’t have access to city water usually drink well or cistern water, Murphy said.
Fluoride occurs naturally in ground water. Daviess County’s average level is 0.3 to 0.4 parts per million, Cecil said.
OMU adds 0.6 parts per million in order to maintain an average of 1 part per million, he said.
OMU checks fluoride levels three times a day in the 13 million gallons a day it treats for about 90,000 customers, Cecil said.
Kentucky cities with a population of more than 3,000 are required to provide fluoridated water, he said. There are 138 such cities, Murphy said.
Cities with 1,500 to 2,999 people — of which there are 39 — can do so on a semivoluntary basis where the oral health office provides startup equipment, Murphy said.
The 29 towns with fewer than 1,500 people fluoridate on a voluntary basis, he said.
“Kentucky leads the nation in the percentage of water plants that provide fluoridated water,” Murphy said, citing a 99.6 percent rate.
For more information, visit the Web sites of the Centers for Disease Control and Prevention (www.cdc.gov) or the American Dental Association (www.ada.org).