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Fluoride's Foes Find Support
in Research
Arguments for and against fluoride have changed in the 24
years since a large number of Utahns last confronted them in
the ballot booth, but one thing has not: the charged emotion
of the debate.
To most public health officials, doctors, dentists and nurses,
the issue is clear-cut: Thousands of studies over the past 50
years have proved that adding fluoride to the water supply is
the safest, easiest and cheapest way to reduce tooth decay. The
Centers for Disease Control and the American Dental Association
report fluoridated water reduces tooth decay 35 percent to 60
percent.
Arguments to the contrary, they say, are pure bunk perpetuated
by fear mongers.
Opponents counter that there are good reasons not to fluoridate
water. It's wasteful, since much water goes to lawns and laundry.
It's an infringement on the rights of those who do not want fluoridated
water, they say, and insulting to force them to pay for it.
But the most polar argument revolves around the science of
fluoride and its effects on the body and teeth.
It is that issue that will be on the minds of Salt Lake County,
Davis County and Logan voters as they decide Nov. 7 whether to
support fluoridation. Residents of the Cache County cities of
Smithfield, Providence, Hyrum and Nibley will cast nonbinding
votes on the issue.
This is the first big fluoride push since 1976, when Utah
voters narrowly rejected the additive. Tooele voters have turned
back fluoride three times.
Meanwhile, the rest of the nation is increasingly choosing
fluoridation. Close to 150 million people drink fluoridated water,
and Utah, with just 3 percent of its water fluoridated, is the
least fluoridated state.
Opponents who want to keep it that way -- and who often are
accused of relying on suspect research published in obscure journals
-- this time point to studies in the respected Journal of the
American Dental Association (JADA).
John Featherstone, a cavity researcher at the University
of California at Berkeley, wrote in July that fluoride's primary
benefit is topical. His research showed that when fluoride is
applied directly to teeth, it prevents cavities, helps teeth
rebuild enamel when cavities start and inhibits bacteria that
lead to dental decay.
"Fluoride incorporated during tooth development is insufficient
to play a significant role in caries [cavity] protection,"
Featherstone wrote.
Opponents say the study bolsters their argument that topical
applications of fluoride -- toothpaste and fluoride rinses and
gels at the dentist's office or in school -- are the best way
to get cavity-fighting fluoride to those who want it. Ingesting
fluoride is unnecessary, they argue.
Early Benefit: But advocates say fluoridated water is the
best way to get -- and keep -- fluoride on the teeth. Not only
does the fluoride bathe the teeth any time a person swallows
water or eats food prepared with water, it also enters the saliva
through the bloodstream and the saliva keeps coating the teeth
with fluoride throughout the day, says Ariel Thompson of Logan.
Thompson is a former National Institutes of Health dental
researcher and microbiologist who teaches at Utah State University
and the University of Utah.
Fluoride tablets, on the contrary, produce a fluoride spike
in a person's saliva for only about four hours.
It's true that research since the 1980s has proved fluoride's
benefits are mainly for teeth once they have come in, said Michael
Easley, director of the National Center for Fluoridation Policy
and Research in Buffalo, N.Y. That became clear when researchers
found adults, like children, had less tooth decay in communities
with fluoridated water, he said.
But Easley and Thompson disagree with Featherstone's assertion
that fluoride does not play a significant role in strengthening
teeth during their development.
"He is in the minority. There is a definite benefit
for children drinking fluoridated water as their teeth are developing.
That has been the evidence for years," Easley said.
That's just one of many reasons why numerous national medical
organizations -- including the American Dental Association, American
Medical Association and the Centers for Disease Control and Prevention
-- endorse fluoridation. The CDC ranks it among the 20th century's
top 10 public health achievements.
But anti-fluoridationists also point to a second JADA article,
published in June. It notes that fluorosis is increasing throughout
the United States.
Fluorosis, from too much fluoride as teeth are developing,
usually shows up as a white, lacy coating on the teeth. Severe
fluorosis, rarely seen in this country, stains the teeth brown,
causes pits or even breakdown of the enamel. Cosmetic treatments
to get rid of fluorosis are expensive.
Incidence of Fluorosis: David Pendrys, a researcher at the
University of Connecticut's School of Dental Medicine, studied
nearly 2,000 children in Connecticut and Massachusetts, comparing
fluorosis in those who grew up with and without fluoridated water.
While there was more fluorosis in nonfluoridated areas --
Pendrys found fluorosis among 39 percent of those from nonfluoridated
areas and 34 percent from fluoridated communities -- the causes
in both were similar.
In most cases, children with fluorosis were using too much
fluoridated toothpaste -- more than a pea-size amount -- too
often and too young to avoid swallowing it. Improper use of fluoride
tablets was also to blame.
Many of the cases stemmed from tablets prescribed before
1994, when the dosage of fluoride given children and infants
was higher. But in some cases, doctors and dentists had prescribed
supplements to children drinking fluoridated water.
In fluoridated communities, some fluorosis was caused by
use of fluoridated water to mix powdered baby formula -- before
manufacturers reduced fluoride additives in 1979 -- Pendrys found.
Jay R. West, a Layton orthodontist, says that although he
has seen significant amounts of fluorosis in his practice, he
was astounded by the levels reported in the study.
"One has to wonder if the addition of more fluoride
to the dental environment through drinking water is a wise decision
at this time," West said.
Mark Flack of Salt Lake City, one of the few dentists publicly
fighting fluoridation, says more research is needed on fluoride's
effect on the body, whether it causes cancer or brittle bones
and hip fractures, and whether fluoridated water can bring on
lead poisoning.
"You could put the entire National Institutes of Health
on a 100-year study on fluoride alone and they'd never have enough
to study this right," he said.
The study opponents use to question a link between fluoride
and lead poisoning was published by Roger Masters, a political
scientist, and Myron Copland, a chemical engineer, in the International
Journal of Environmental Studies, printed in Malaysia last year.
They studied blood samples of 280,000 Massachusetts children
and concluded that kids in communities with fluoridated water
have higher lead levels in their blood. The pair concluded that
the form of fluoride used to treat community water causes human
cells to absorb lead.
Scientists who took the children's blood samples, however,
decried the study's conclusions, and an Environmental Protection
Agency chemist wrote a rebuttal paper claiming that it is chemically
impossible for the fluoride to behave in water as Masters and
Copland claim it does.
The larger scientific community also dismisses as "ridiculous"
the research linking fluoride to cancer. Opponents say fluoride
changes the enzymes in the body, weakening its ability to fight
cancer. If there were a link, it would have shown up after 50
years of fluoride use in community water systems, say advocates.
Studies linking fluoride to hip fractures, however, have
been mixed. Opponents point to 1990 research involving senior
citizens in Brigham City, performed by University of Utah researchers.
Brigham City began fluoridating its water in the 1960s.
While they found a possible link between fluoride and hip
fractures, the researchers noted their study was far from conclusive.
Fluoride proponents say they now have all the assurance they
need that there is no connection, particularly after an exhaustive
study involving 9,000 people reported this month in the British
Medical Journal.
"The hip fracture issue is about put to bed," Thompson
says.
Opponents often say it's unfair to fluoridate a community's
water system when some people are allergic.
Flack says he occasionally sees patients with a sensitivity
to fluoride if not an outright allergy. It shows up as a red
rash or cracks and blisters around the mouth.
But fluoridation proponents argue it is the high level of
fluoride in toothpaste, 1,000 parts per million, that causes
sensitivities, and that water, fluoridated at 1 part per million,
will not have the same effect.
Joseph Newton, a retired Salt Lake City pediatrician who
gathered petition signatures to force fluoride onto Salt Lake
County's ballot, says he himself is sensitive to fluoridated
toothpaste.
The solution, he adds, is simple: Change to a different toothpaste
and reach for a glass of fluoridated water.
© Salt Lake Tribune |
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