Systematic review of water fluoridation
BMJ 2000; 321 doi: https://doi.org/10.1136/bmj.321.7265.855 (Published 07 October 2000) Cite this as: BMJ 2000;321:855All rapid responses
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Editor - An excellent paper recently focused on advantages and
possible negative side effects of water fluoridation 1. It recalls to our
minds the fascinating story of humans and environment: they continuously
look for the best milieu for their life, they think to do the safest
choice, but…in the Earthly Paradise a snake might be hidden.
Could you imagine an Earthly Paradise better than that of Minamata bay,
facing the Shiranui Sea in Japan? Blue sea, white sand, green shrubs,
burning sun , lightening stars . But… in the mid-1950, some unexplainable
occurrences brought panic to Minamata: birds were strangely dropping from
the sky, cats committed "suicide", people began to notice a " strange
disease" enclosing numbness in limbs and lips, speech slurring, vision
constriction, incontrollable shout, involuntary movements,
unconsciousness.
The snake had been constituted by 27 tons of mercury compounds dumped into
Minamata bay from 1932 to 1968 by a company developing plastic, drugs and
perfumes through the use of acetaldheyde, which is produced using mercury
as a compound. Over 3000 victims have been recognized as having Minamata
disease, due to a degeneration of the nervous system 2,3.
A dream was crushed: good health in a pure, uncontaminated area is not
allowed in the absence of safety controls.
Then humans thought they have learned the lesson and pointed to construct
safer and safer buildings, as a modern Earthly Paradise with any comforts
and far from environmental risks. But….in the mid 1970, some unexplainable
occurrences brought concern : somatic and psychological symptoms of
people living in recently built houses, enclosing arthralgia, eye/ throat
irritation, cough, rash, pruritus, enhanced/ abnormal odor perception,
visual disturbances, mild to sever headache, nausea, vomiting,
restlessness and sleeplessness. Some volatile component of the building
material or some biological contaminant ( endotoxin, mycotoxin, trace
elements?) might be causing this unique systemic syndrome, the so-called
sick building syndrome 4,5.
Another dream is crushed: good health in an artificial, sophisticated
structure is not allowed also in the presence of the better available
safety controls, or perhaps, by the presence of modern devices such as
humidifiers and ventilation system.
Nature is less perfect and more vulnerable than we used to surmise: for
humans living on the earth crust, each Earthly Paradise has its snake. Is
there any chance of winning for human people against environment? Nothing
is due, neither the assumption that water fluoridation is just useful
without any side effect….
Piero Stratta, Alessandra Messuerotti and Caterina Canavese
Department of Internal Medicine, Section Nephrology,
S.Giovanni Molinette Hospital, Torino, Italy
Piero Stratta
Department of Internal medicine, Section Nephrology,
S.Giovanni Molinette Hospital, Corso Bramante 88 , 10126 Torino, Italy
References
1) Mc Donagh MS,Whitny PF, Wilson PM,Sutton AJ,Chestnutt J, Cooper
J,Misso K,Bradley M,Treasure E, Klejnen J. Systematic review of water
fluoridation. BMJ 2000: 7265:855-859 ( 7 October)
2) Minamata Disaster
http://gurukul.ucc.american.edu/ted/MINAMATA.HTM
http://vest.gu.se/~bosse/Mercury/Culture/Events/minamata.html
4) Bourbeau J, Brisson C, Allaire S. Prevalence of the sick building
syndrome symptoms in office workers before and after being exposed to a
building with an improved ventilation system. Occ Envir Med 1996; 53: 204-
210
5) Redlich CA, Sparer J, Cullen MR. Sick building syndrome. Lancet
1997;349:1013-1016
Competing interests: No competing interests
Sir - The long-awaited systematic review (1) indicates that the
benefits and risks of water fluoridation balance each other in that a
median of 6 people would need to
receive fluoridated water for one to benefit while 6 people would have to
be exposed to it for one additional person to develop dental fluorosis.
The report also shows that in artificially fluoridated areas on average
48%, nearly half of the population, suffers from this condition. Since
dental fluorosis, whether of aesthetic concern or not, is the first
visible sign of poisoning by fluoride, which is as toxic as arsenic or
lead, this shows that about half the population in these areas is
suffering from some level of harm. This suggests that water fluoridation
is an unacceptable method of reducing dental decay.
The benefits, however, may be over-estimated while the risks may be
grossly under-estimated. A confounding factor which was repeatedly pointed
out to the review panel, but which failed to be taken into account, is
that fluoride delays tooth eruption. In comparing children of similar age,
this biases the results in favour of fluoride (2).
The York review does point out the possibility of adverse effects of
fluoride on the thyroid gland. Since fluorine displaces iodine from its
compounds, this finding is
not surprising. It is likely that this effect of fluoride on the thyroid
is at least one of the factors, if not the major one, in causing the delay
in tooth eruption. It may
also be a factor in increased neonatal death rate described by Schatz in a
fluoridated area of Chile (3), a paper which was submitted to the review
but which seems not to have been commented on. Birmingham and the West
Midlands, fluoridated since the early 1960s, have one of the highest
neonatal death rates in Britain (4) and also an exceptionally high level
of diabetes (5).
Since the established view is that fluoridation is "perfectly safe",
little research into possible adverse effects has been carried out on
human populations drinking
artificially fluoridated water, and correlations fail to be made between
increasing prevalences of illness and water fluoridation. There is,
however, a large body of
experimental and animal evidence, studies which fell outwith the remit of
the York review, which attest to the toxic effects of fluoride on the
stomach, kidneys, pancreas, thyroid gland, brain and immune system, as
well as on bones and teeth. Since animal studies are the gold standard of
drug safety testing, this evidence should be considered before mass
medicating any further sections of the community. If the York review shows
anything, it is that there should be a moratorium on all current
fluoridation schemes until clearer evidence of benefits and risks becomes
available.
Sheila L.M. Gibson, M.D., B.Sc, M.F.Hom.
Robin G. Gibson, M.B., F.R.C.P., D.C.H., B.D.S., F.F.Hom.
Glasgow G41 5PJ.
References.
1.McDonagh, M.S., Whiting, P.F., Wilson, P.M. et al. Systematic
review of water fluoridation. BMJ 2000, 321, 855-859.
2.Gibson, S.L.M. and Gibson, R.G. Authors did not compare like with
like. (Letter). BMJ, 1998, 316, 231.
3.Schatz, A. Increased death rates in Chile associated with
artificial fluoridation of drinking water, with implications for other
countries. J. Arts, Science and Humanities, 1976, 2, 1-17.
4.Stillbirth and neonatal death 1991-1994. Report of the National,
Regional, District and Unit mortality rates. West Midlands Perinatal
Audit.
5. Diabetes. Partners in Health, 1992. Chapter 2. West Midlands
Regional Health Authority.
Competing interests: No competing interests
I hope that Roger Shlafly MEANT to say that he'd like to see a study
to compare results between fluoride toothpaste-brushers and non-fluoride
tooth-paste brushers (rather than those who do not brush at all!).
However, I'd go even further. Let's have a study on those who brush
with fluoride toothpaste and those who brush with non-fluoride toothpaste
- and those who brush with no toothpaste at all. Then we'll know whether
the multi-billion dollar toothpaste hype is about something or nothing. I
don't suppose industry would rush to fund such an experiment.
There is no law which says that one must use fluoride toothpaste. Not
only would it be unworkable, but it would be preposterous. Yet there is a
law which allows force-treatment of whole populations via the drinking
water 'to reduce the incidence of tooth decay.' Might we soon have some
"expert" advocating dosing the water with aspirin to reduce the risk of
heart attacks and strokes? If you think that sounds mad, remember the
press reports about an American psychiatric "expert" who seriously
advocated adding valium to the drinking water 'to calm people downn.'!
Competing interests: No competing interests
Editor.
Dr Paul Connett points out that the Review by McDonagh et al avoided
mention of the crucial dose-response evidence of the association between
hip-fracture and fluoridation obtained by Li and his co-workers. Had this
evidence been presented it would have been impossible for McDonagh et al
to conclude that there was no clear evidence of negative effects of
fluoridation other than dental fluorosis. The report of Li et al; as
outlined by Dr Connett, so clearly establishes a causal association
between hip-fracture and fluoridation that to deny it would be illogical.
The reports of Phipps et al. and that of Professor Hausen, in the same
issue of the BMJ, are also rendered transitory aberrations of Science by
Li's report.
Michael Innis FRCPath; FRCPA
Competing interests: No competing interests
I'd like to see a study that distinguishes between those
who brush their teeth with a fluoride toothpaste, and
those who do not brush at all. Also, whether the benefit
is systemic or topical. Such information is of practical
utility to those who live in an unfluoridated area.
Competing interests: No competing interests
In 1983, when Lord Jauncey ruled that fluoridation was unlawful (Mrs C. McColl v. Strathclyde Regional Council)at the Edinburgh Court of Session, after the longest running case in the history of Scotland, (201 days), that should have been the end of the matter.
At that time, the West Midlands and North East had been artificially fluoridated for almost 20 years. Although the Jauncey verdict held no sway in England, Wales and Northern Ireland, the implications were clear: Westminster could be in breach of the law for illegally mass-medicating millions of people for almost twenty years, whether individuals agreed or not . . . to achieve a claimed reduction in tooth decay!
What happened next can best be described as "bizarre". The Tory Government moved to legalise fluoridation.
In a supposedly free vote in the House of Commons, the final ballot figures on the Water (Fluoridation) Bill, 1985 were: For F - 165; Against F - 82; Abstained - 399, excluding the four Tellers. Even known anti-fluoridation MPs either voted with the Government, or abstained, leaving observers to question whether the vote had, in fact, been free. Two thirds of the British electorate were effectively disenfranchised on that day. Kenneth Clark assured the House that this would not signal the start of any campaign to promote fluoridation. However, the Dept. of Health continued to fund the British Fluoridation Society with taxpayers' money to promote it.
Over the next decade, fluoridation 'battles' raged across the north of England and in N. Ireland and the practice was robustly rejected, but this did not deter health authorities from asking the water companies to fluoridate. It was apparent that the Government was not prepared to take NO for an answer. But many water companies said NO, stating that Government indemnities to them were "insufficient" and that their customers did not want it. It is, after all, the job of a water company to provide potable drinking water. It is not the job of water companies to convey medication or treatment to its customers. In 1998, in the High Court in London, Justice Collins ruled that Northumbrian Water was perfectly entitled to refuse to fluoridate. With breathtaking arrogance, a spokesman for Newcastle and North Tyneside Health Authorities commented: "Well, we'll have to change the law."
In October, 1998, the NPWA presented the (then) public health minister Tessa Jowell with 30,000 signatures, quickly gathered, calling for a full, independent public inquiry into water fluoridation. The government's response, in 1999, was to commission "a once and for all . . . unchallengeable . . . systematic review" (Frank Dobson).
The White Paper on health stated that there would be a review of the effects of fluoride on HEALTH. If properly conducted, this would have examined the effects of fluoride exposure from all sources, such as from food, beverages, toothpaste, mouth rinses, drops, tablets, gels, medicines, anaesthetics, herbicides, pesticides and even from the polluted air that we breathe. It would also have examined the PRODUCT which is widely used in artificial fluoridation schemes - which contains Arsenic, Lead, Beryllium, Cadmium, Vanadium, Mercury and even Radionuclides. It would have fulfilled the recommendations of the World Health Organisation: "Dental and public health administrators should be aware of the total fluoride exposure in the population before introducing any additional fluoride programme for caries prevention."
But what happened? We see, published in BMJ, a review whose narrow criteria excluded all animal studies, all biochemical studies, all mathematical models and all investigations of fluoride exposure except from water fluoridation! The review made no distinction between naturally-occurring Calcium fluoride and hexafluorosilicic acid, the industrial toxic waste product of the phosphate fertiliser industry. Government advisers still refuse to make any distinction between these two "fluorides" and no safety testing data exists to show that H2SiF6 is safe for human consumption.
The criteria for the York review were further narrowed to exclude more than 100 studies on the adverse effects of fluoride on the thyroid gland, submitted by Parents of Fluoride Poisoned Children, based in Vancouver. (There are more than 40,000 studies on the adverse effects of fluoride on health, which were not considered by the review.).
Despite the structural inadequacy of the review it found that 48% - nearly half - of populations living in fluoridated areas exhibit dental fluorosis to some degree, 12.5% of which is "aesthetically concerning." The victims had no possibility of avoiding the risks that a "public health measure" had visited upon nearly half of the fluoridated population.
Baroness Hayman conceded to Parliament on 20 April 1999 that "dental fluorosis is a manifestation of systemic toxicity." Bodily poisoning. This concurs with the published scientific evidence, but government advisers and dentists dismiss this visible evidence as "merely a cosmetic effect."
Mass medication or treatment for non-contagious, non-lifethreatening conditions is a direct violation of the Convention of Human Rights and Biomedicine.
Tooth decay is caused by poor nutrition and/or inadequate oral hygiene. This should be addressed as a public health education issue.
There is no scientific evidence of "fluoride deficiency" but there is a vast body of published evidence of adverse health effects resulting from fluoride exposure. Even the York review found that it damages people.
How much fluoride have you and your patients been exposed to today, or this week, or this month? If you do not know the answer, then what 'dose' could you possibly prescribe for your patients? And if your patients refused to take it, do you have the right to force it down them?
Water fluoridation contravenes the ethics of medicine and
science.
We are renewing our call for a full, independent public inquiry. The medical profession should support us.
Competing interests: No competing interests
Editors.
Last week news of the “York Study” came out of Great Britain
intended to reassure us that water fluoridation was perfectly safe. I
guess the
York Study wasn’t actually a study as studies go, because this study
didn’t study
animals or people, it simply studied studies. Although this was touted
to be
the study to end all studies, almost immediately both the Green Party
and the Fluoride Action Network published their studies of the York
Study. These were then studies of the study that studied the studies.
The studies of the study that studied the studies pointed out that
this study that had studied the studies had left some 3000 studies
unstudied, and they called for a study of studies that would study all
studies
and therefore not necessitate a study of the study of the studies as
this
study had done. They were quick to stress that funding for studies is
difficult to obtain and that while studies that study studies are not
so unusual, almost no one will give grants to do a study of studies that
study studies. It would be even more difficult to obtain funding to
study the studies not studied by a study which studied the studies
such that people studying the issue won't know which studies have been
studied and which studies were excluded in the studies that studied
the studies. Study, schmuddy just don’t put it in my water.
Don Caron
2017 E. Bismark,
Spokane, WA 99207
Competing interests: No competing interests
Dear Editor,
As an invited peer reviewer of the York Review of fluoridation,
please
permit me to add a few concerns about this report and the spin it has been
given in the press. While a number of people have correctly pointed out
that this York Review deals a very serious blow to water fluoridation
based
upon the findings of a much lower benefit for caries reduction than
claimed
by promoters, and a much higher level of dental fluorosis than is
acceptable, I am very disturbed that the authors are not making it clear
that dental fluorosis is in fact an indication of a toxic effect of
fluoride, in a similar fashion that the blue line on teeth was an early
indicator of lead poisoning. The fact that neither tooth mottling nor the
blue line causes any obvious pain is beside the point. Tooth mottling
indicates that fluoride has poisoned the enzyme involved in removing
protein from between the mineral prisms prior to enamel formation
(DenBesten, 1999). It raises - or should raise -the obvious question of
what other enzymes might have been poisoned by fluoride which have no
visible effects. British researcher Jennifer Luke (1998) may have answered
this question in her Ph.D thesis. It would appear that fluoride
accumulates
in the human pineal gland and experiments in animals indicate that
fluoride
lowers melatonin levels. Unfortunately, the York reviewers didn't consider
Luke's work, nor others' work on the thyroid gland or many animal
experiments conducted over the last 10 years which wave very large red
flags of concern about fluoride's potential health effects. I have
reviewed
many of these concerns elsewhere (see http://www.fluoridealert.org).
Turning to an issue that the York team did examine, the authors claim
that
there is no evidence of a relationship between increased hip fracture in
the elderly and exposure to fluoride in drinking water. I feel that
properly interpreted the current literature provides considerable evidence
of such harm.
Paul Wilson of the York team is quoted in an Associated Press report
(Oct
5, 2000) as saying that "the studies he examined tracked the effects of up
to 4 mg per liter in drinking water". This is not accurate. In their
review
of hip fracture the York team included an unpublished study by Li et al
(1999) which they indicated showed no association between fluoride and hip
fracture. The York team was only able to draw this conclusion because they
limited their comparison to hip fractures in the village with low fluoride
levels with the hip fractures at 1 ppm (i.e. 1 mg per liter). When I
reviewed this study, as part of my invited review, I found Li et al
examined the hip fracture rates in six Chinese villages with different
water fluoride concentrations: 0.25 - 0.34 ppm; 0.58 - 0.73 ppm; 1.00 -
1.06 ppm; 1.45 - 2.19 ppm; 2.62 - 3.56 ppm, and 4.32 - 7.97 ppm. The
authors chose the village with 1 - 1.06 ppm fluoride for their baseline
for
comparison. Their reported odds ratios for hip fracture were 0.99; 1.12;
1.00 (control); 2.13; 1.75 and 3.26. In other words they found an
approximate doubling of the hip fracture rate for fluoridation levels over
1.5 ppm and tripling for water levels over 4 ppm.
In my view, the York team did a disservice by confining themselves to
hip
fractures in villages with fluoride concentrations at 1 ppm or below. Paul
Wilson compounds this disservice by claiming that they actually considered
studies which looked at effects up to 4 ppm (4 mg per liter), when in this
critical case they clearly did not.
Paul Wilson further distorts the scientific record when he claims in
the
same AP report that, the fear of osteoporosis has never been based on
strong evidence. In actual fact, since 1990 there have been 18 studies (4
unpublished, including one abstract) which have examined a possible
association with hip fracture in the elderly and fluoride in the drinking
water. 10 of these found a positive association (increased hip fracture
rates) and 8 did not. Moreover, these studies were prompted by the fact
that when fluoride (50 - 80 mg per day) was used to treat patients with
osteoporosis in an effort to harden their bones and reduce fracture, it
was
found that the treatment increased not decreased hip fracture rates
(Hedlund and Gallagher, 1989 and Riggs et al, 1990). The fact that 50% of
all the fluoride that we swallow accumulates in our bones should give us
pause. Increased hip fracture in the elderly is not a minor problem. One
in
four of those suffering a hip fracture in the U.S.are dead within a year
of
their treatment and one in two never regain an independent existence.
It is unfortunate that the York team has managed to convey the
message that
there is "no evidence of harm" when in actual fact there is "mixed
evidence
of harm". A critical difference. They also beg the question of how one
should resolve mixed epidemiological findings when one is giving advice to
a government which is considering putting a toxic substance into the
drinking water of every man, woman and child in the population. The
precautionary principle says "If in doubt, leave it out". As far as hip
fractures are concerned, the York Team says, based upon meta-analysis of a
mixed bag of poor studies, we find no evidence of harm. Not very
reassuring
and not very helpful when they themselves avoided the key piece of
dose-reponse evidence presented by Li and co-workers.
Dr. Paul Connett,
Professor of Chemistry,
St. Lawrence University,
Canton, NY 13617.
Competing interests: No competing interests
One of the objectives of this study was said to be a comparison of
water fluoridation and other strategies. Sadly this this was simply a
comparison of water fluoridation with fluoride from other sources. There
are other methods of preventing dental decay and they are more effective
than flouride, although probably more expensive.
Kowash et al have shown(1) that a long term health education
programme for mothers with young children improved not only the dental
health of the children but that of the mothers. Xylitol, a natural
substance extracted commercially from birch bark, has been shown to give a
93% long-term caries risk reduction when children chew gum containing it
for at least a year before the permanent teeth erupt (2). If mothers chew
gum containing xylitol they can prevent, or at least delay, the
transmission to their children of the bacteria that cause decay (3).
Opponents of water fluoridation have argued that flouride simply
delays the eruption of teeth and postpones decay. If this is true - and
the authors of the York review found only one study that properly
investigated this - even the uncertain benefits found in the review may
prove to be illusory. They are certainly smaller than the benefits of
using xylitol.
1. Effectiveness on oral health of a long-term health education
programme for mothers with young children MB Kowash et al British Dental
Journal 188(4) Feb26 2000
2. The optimum time to initiate habitual xylitol gum chewing for
obtaining long-term caries prevention Hujoel et al J Dent Res 1999 Mar
78(3) 797-803
3. Influence of maternal xylitol consumption on acquisition of mutans
streptococci by infants Soderling et al J Dent Res 2000 Mar 79(3) 882-7
Competing interests: No competing interests
Bottled water for Aussie hospitals-March 16 2005
Sometime in the last two weeks, bottled water replaced the tap water
supplied to patients in my local public hospital - one of several large
hospitals in the Brisbane metropolitan area. Brisbane tap water isn't
flouridated, but still tastes of chemical treatment with chlorine.
Patients have often complained of the taste of the tap water. bottled
water should be an improvement, but it will be interesting to see if there
are any cases of mild dehydration resulting from the more complicated
process of obtaining water - eg. you simply can't get it from the tap in
the room.
Competing interests:
None declared
Competing interests: No competing interests