From Chemical & Engineering News August 16, 2004
Volume 82, Number 33
pp. 35-36
IS FLUORIDE REALLY ALL THAT SAFE?
The Fluoride Deception, by Christopher Bryson, Seven Stories Press,
2004, 374 pages, $24.95 (ISBN 1-58322-526-9)
REVIEWED BY SHELDON KRIMSKY
"The Fluoride Deception" reads like a whodunit. There are
conspiracies, cover-ups, human casualties, and broken careers. The
prime suspects in this toxic thriller are compounds of fluoride; the
coconspirators represent industry, the military, and the public health
community. At the book's ending, the suspect chemicals are not proven
guilty beyond a reasonable doubt, but we are left with compelling
evidence that powerful interests with high financial stakes have
colluded to prematurely close honest discussion and investigation into
fluoride toxicity.
Christopher Bryson has woven together an impressive body of evidence
that brings into question the near universally held view in the
medical and public health communities that fluoridation of public
water supplies at current levels (about 1 ppm) is unambiguously safe
and does not involve any serious health or environmental trade-offs.
Bryson conducted extensive interviews, read many scientific papers,
and burrowed through archival sources (there are more than 100 pages
of reference notes) to make his argument that fluoride toxicity, even
at the levels found in public water supplies, is not a closed case.
Some private interests, he alleges, will seek to destroy careers to
ensure that scientific studies that raise doubts about the safety of
fluoride never get funded--or if they do, never get published.
Few people of prominence will stand up and contest the issue of the
safety of fluoride compounds, Bryson claims. One exception is Arvid
Carlsson, a Swedish pharmacologist who shared the 2000 Nobel Prize in
Physiology or Medicine. In a postscript to the book, Carlsson writes:
"Fluoride is a pharmacologically very active compound with an action
on a variety of enzymes and tissues in the body already in low
concentrations. In concentrations not far above those recommended it
has overt toxic actions." Carlsson was one of the scientists who
helped persuade the Swedish Parliament to ban fluoridation of drinking
water in that country.
The book summarizes 50 years of fluoride uses in steel, aluminum,
phosphate, gasoline, uranium enrichment, refrigerants, and plastics.
Bryson shows how fluoride became the "lifeblood of the modern
industrial economy." Notwithstanding fluoride's broad industrial
applications, its airborne emissions, and its toxic by-products, the
public's awareness of fluoride comes primarily from its uses in
drinking water, toothpaste, and preadolescent fluoride treatments as a
prophylaxis against dental cavities.
There are many resemblances between the history of fluoride regulation
and that of other toxic substances. The exigencies of World War II
blinded public health regulators to medical reports of occupational
hazards from fluoride exposure in those industries where compounds of
fluoride were used or produced. The U.S government did not take kindly
to lawsuits filed by farmers for gaseous fluoride damage to their
families, their cattle, and their crops, an unintended by-product of
nuclear weapons facilities during the Manhattan Project. Postwar
economic growth served as a convenient excuse to ignore evidence that
communities were exposed to unhealthy levels of airborne fluoride
emissions.
But what is distinguishable about fluoride politics is the connection
between this ion and the prevention of dental cavities. Bryson shows
us how fluoride's dental applications were skillfully used by
corporate stakeholders in their campaign to derail more stringent air
and occupational standards for industrial fluoride emissions.
Similarly, defense lawyers exploited the positive side of fluoride to
protect companies from worker-injury suits.
AS THE SAYING GOES in the public health community, adopting an
antifluoridation position is a career breaker. This is illustrated in
the book by the case of Phyllis Mullenix, a neurotoxicologist hired by
the Forsyth Dental Center in Boston to investigate materials used in
dentistry. Mullenix found evidence of fluoride neurotoxicity in
experimental rats. Mullenix showed that with chronic exposure, the
fluoride ion could cross the blood-brain barrier. Moreover, when
fluoridated water was fed to pregnant rats, she found the offspring
exhibited behavior resembling hyperactivity.
PHOTODISC
Mullenix recalls the response of a Forsyth administrator to her
findings: "You are going against what the dentists and everybody have
been publishing for 50 years, that this [fluoride] is safe and
effective. You must be wrong. ... You are jeopardizing the entire
support of this entire institution. If you publish these studies, NIDR
[the National Institute of Dental Research] is not going to fund any
more research at Forsyth." Her studies were published in
Neurotoxicology & Teratology. But within days after the paper's
acceptance, her contract with Forsyth was not renewed.
Bryson's investigations into fluoride science led him to a 1962
unpublished study conducted at Kettering Laboratory at the University
of Cincinnati, which he found in the basement archive of the
laboratory. An industry group contributed nearly half-a-million
dollars for a series of toxicological studies that they believed would
help them against worker claims of crippling skeletal
fluorosis--thickening and fusing of spinal vertebrae.
In one of the key experiments, 42 beagle dogs were exposed to calcium
fluoride dust for six hours a day, five days a week--simulating human
occupational exposure. According to the results of the study, calcium
fluoride damaged the lungs and lymph nodes of the dogs. If released,
the study could have provided the critical evidence needed to raise
the industrial standard on fluoride emission limitations.
"The Kettering data pointed an arrow directly at the heart of key
modern industrial enterprises, where the extraordinary incidence of
emphysema in workers potentially 'dwarfed' even the silicosis crisis
of the 1930s," Bryston writes. He quotes one toxicologist who was
given the long-suppressed study data, who said, "The fact that the
Kettering data were not published or made available is a crime against
American workers--with profound health consequences for the rest of
the nation."
The positive spin of this unpublished report was that the university
researchers did not manipulate the science to give the sponsors what
they wanted to hear. Scientists refused to fudge the data or give the
study a proindustry interpretation. However, there is also a negative
spin. The academic investigator at the University of Cincinnati either
chose not to or lacked the contractual rights to publish the results.
According to Mullenix, "The Kettering Laboratory's long-ago
suppression of the dog study helped to perpetuate a cover-up of
fluoride's potential for harm as an air pollutant."
Even today there are no legal constraints against the suppression of
scientific data from privately funded studies. Recently, New York
State Attorney General Eliot Spitzer filed suit against a major
pharmaceutical company, charging that it had suppressed clinical trial
data that was valuable to the medical community on a drug used to
treat adolescent depression. A small group of prominent journals have
adopted a policy that they will not publish studies unless the authors
affirm their control over the data and publication. Some members of
the medical community are calling for a public database on clinical
trials, so that data unfavorable to a sponsor will not be suppressed.
<snipped some>
"The Fluoride Deception" will leave any open-minded readers feeling
uneasy about the acceptable levels of fluoride in drinking water, as
well as the cumulative sources from dental hygiene products. But the
deeper lessons of this story, going back to classified military
research during World War II, are the book's insights into the threats
to open inquiry in public health and environmental science. Premature
closure of debate in science undercuts one of its unique features--a
feature that distinguishes it from other forms of fixing
belief--namely, science's self-correcting function. Without a
scientific culture that supports reexamination of "no risk" results,
however strongly held, we may find our public health and environmental
policies resting on weak or faulty foundations, which can prolong our
blindness to preventable illnesses.
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Sheldon Krimsky is a professor of urban and environmental policy and
planning at Tufts University. He does science policy research and is
the author of "Science in the Private Interest."