Despite shortage, fluoride’s in

In news that is sure to please at least four out of five dentists, the Southern Nevada Water Authority has announced it will continue to add fluoride to the local water supply despite a nationwide shortage of the cavity-fighting chemical.

Increased demand and declining production are being blamed for supply problems that have temporarily halted fluoridation in towns across the East and Midwest. Nearly 1 million people in Fort Worth, Texas, have gone without fluoride in their drinking water for the better part of a month, and the shortage also is being felt in Canada.

But water authority spokesman J.C. Davis said no such trouble is expected here, thanks to the agency's long-term contract with a Florida manufacturer of fluoridation chemicals.

The authority has been buying hydrofluorosilicic acid from Jacksonville-based LCI, Ltd., since 2000, when fluoride was first added to local tap water under a mandate from the Nevada Legislature.

Now the authority's two water treatment plants each use an average of one tanker truck load of fluoridation chemicals a week. During the summer, when water use is at its peak, deliveries increase to two tanker trucks a week.

"We're a major customer," Davis said. "We haven't had any problem getting fluoride."

Other LCI customers have not been so lucky. According to a report in the Boston Globe, the town of Needham, Mass., went without fluoride for several weeks because of a shortage experienced by the supplier.

Davis said much of the growing demand for fluoridation chemicals can be traced to a single source: the Metropolitan Water District of Southern California, which serves 18 million people from Los Angeles to San Diego.

Metropolitan began adding fluoride to drinking water for the first time in October.

"They took an already reasonably tight market and tightened it up quite a bit just by virtue of the volume (of water) they move," Davis said.

If they haven't already, Metropolitan officials can expect to hear an earful from some residents who worry about the long-term effects of fluoride and others who believe it is being used by the government as a "brain-washing agent," Davis warned.

"I know because I remember the phone calls. Fluoridation is always contentious. It's one of those polarizing issues."

The American Dental Association cites studies showing that water fluoridation reduces dental decay by as much as 40 percent. The federal Centers for Disease Control and Prevention ranks the fluoridation of drinking water supplies as one of the top 10 public health achievements of the 20th century.

Since fluoridation began in the U.S. in 1945, 43 of the nation's 50 largest cities have taken up the practice. Nearly two thirds of Americans now drink fluoridated water on a regular basis.

At the water authority's Alfred Merritt Smith and River Mountains treatment facilities, fluoridation chemicals are added near the end of the disinfection process, shortly before the water is delivered to the authority's member utilities in Las Vegas, Henderson, North Las Vegas and Boulder City.

Davis said the total concentration of fluoride in local drinking water is less than one part per million, which is roughly equivalent to one teaspoon of water in an above-ground swimming pool. About one third of that fluoride occurs naturally in the Colorado River, which supplies about 90 of the valley's water supply.

Outdoor landscaping soaks up two thirds of all the water the authority delivers.

Protecting its customers from a fluoride shortage has come at a price for the water authority.

In April, the cost of fluoridation chemicals jumped 88 percent. Last year, the authority spent $300,000 on hydrofluorosilicic acid. This year, the same quantity will cost about $550,000.

The authority spends about $88 million a year to pump water from Lake Mead, clean it to federal safety standards and deliver it to its member utilities. Of that total budget, about $2.4 million is spent on chemicals.

About two-thirds of the authority's treatment and delivery costs go to buy electricity, which Davis said is needed in large quantities to run pumps and disinfect water by "zapping it" with an enormous amount of electrical current in a process called ozonation.

"It's a little power intensive to produce your own lightning," he said.

In that respect, the increased cost of fluoride is little more than a drop in the bucket or spoon of water in the backyard pool.

"It's more expensive on a small enough scale so it's not going to show up on anyone's bill," Davis said.

The American Dental Association recommends that preschoolers drink at least one pint of fluoridated water each day. By the time a child is old enough to attend school, the recommendation is for a quart.

According to the association, fluoride builds strong, decay-resistant enamel in children 6 months to 16 years old and can help prevent tooth and root decay in adults.

Reverse osmosis treatment systems will filter out fluoride from tap water, but most household filtration systems will not.