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Excerpts from NRC Report
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Water is for everyone, fluoridation toxins are not
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Fluoridation-Free Ottawa - Ottawa Libre de Fluoration
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DIRECTORY: Health
> EPA
Fluoride Standards > NRC
Review (2006) > Excerpts from NRC Report
FAN Science Watch
March 28, 2006
Issue #28: Excerpts
from NRC Report
by Michael Connett
Last week, the National
Research Council (NRC) released its long-awaited review of EPA’s
safe water standard for fluoride (4 ppm).
As reported by the media,
the NRC concluded that EPA’s safety standard for fluoride
is not safe and “should be lowered.” According to the
NRC, EPA’s “safe” standard (4 ppm) puts a person
at increased risk for both tooth and bone damage (“severe
dental fluorosis” and bone fracture).
While most of the press coverage so far has focused
on NRC’s concerns with teeth and bone, there are many other
serious concerns expressed in the NRC report.
To give readers an indication of the other concerns
expressed by the NRC, we have reproduced a series of excerpts from
the report (see below).
The excerpts detail the various systems in the
body (e.g. nervous, endocrine, and immune) that fluoride may damage,
and how these effects may be enhanced or mediated through fluoride’s
interactive/synergistic effects with other compounds (e.g. iodine
deficiencies and aluminum overload).
When one couples the multitude of serious health
concerns expressed by NRC, with their uncertainties on what the
various safe vs. toxic doses are, it should cause a great deal of
concern.
Here, for example, are what two of the NRC panel
members – Dr. Kathleen Thiessen and Dr. Robert Isaacson –
had to say about the relevance of NRC’s report to the water
fluoridation program (see: http://www.portlandtribune.com/archview.cgi?id=34527
)
However, some of the research that is validated
by the report suggests that water-fluoridation levels advocated
by Hamilton and Ferre may be unhealthy, two members of the NAS
panel said in interviews with the Portland Tribune.
NAS panel member Kathy Thiessen, a former senior
scientist at Oak Ridge National Laboratory who has studied fluoride
for the EPA, said the report showed “the potential is there”
that water fluoridation is unhealthy. As for the studies finding
that higher levels damage children’s IQ, she said it’s
possible water fluoridation levels may have a similar, albeit
reduced effect. She said in her personal opinion the research
suggests “most people should minimize their fluoride intake”
— which includes avoiding fluoridated water.
“I think you can look at most chapters
of this report and say, ‘Whoa,’ ” she said.
“We have made major strides from previous (looks) at this
topic.”
NAS panel member Robert Isaacson, a distinguished
professor of neurobehavioral science at the State University of
New York in Binghamton, agreed, saying that the possible effects
on endocrines and hormones from water-fluoridation are “something
that I wouldn’t want to happen to me if I had any say in
the matter.”
The report “should be a wake-up call,”
he added.
For more information, and news articles, on NRC’s
review, see: http://www.fluoridealert.org/health/epa/nrc/index.html
###
Excerpts from: “Fluoride
in Drinking Water: A Scientific Review of EPA’s Standards”
(National Research Council, 2006)
FLUORIDE’S EFFECTS ON THE BRAIN:
“On the basis of information largely derived
from histological, chemical, and molecular studies, it is apparent
that fluorides have the ability to interfere with the functions
of the brain and the body by direct and indirect means.”
p187
“A few epidemiologic studies of Chinese
populations have reported IQ deficits in children exposed to fluoride
at 2.5 to 4 mg/L in drinking water. Although the studies lacked
sufficient detail for the committee to fully assess their quality
and relevance to U.S. populations, the consistency of the results
appears significant enough to warrant additional research on the
effects of fluoride on intelligence.” p6
“histopathological changes similar to those
traditionally associated with Alzheimer’s disease in people
have been seen in rats chronically exposed to AlF.” p178
“Fluorides also increase the production
of free radicals in the brain through several different biological
pathways. These changes have a bearing on the possibility that
fluorides act to increase the risk of developing Alzheimer’s
disease.” p186
“More research is needed to clarify fluoride’s
biochemical effects on the brain.” p186
“The possibility has been raised by the
studies conducted in China that fluoride can lower intellectual
abilities. Thus, studies of populations exposed to different concentrations
of fluoride in drinking water should include measurements of reasoning
ability, problem solving, IQ, and short- and long-term memory.”
p187
“Studies of populations exposed to different
concentrations of fluoride should be undertaken to evaluate neurochemical
changes that may be associated with dementia. Consideration should
be given to assessing effects from chronic exposure, effects that
might be delayed or occur late-in-life, and individual susceptibility.”
p187
“Additional animal studies designed to
evaluate reasoning are needed.” p. 187
FLUORIDE’S EFFECTS ON THE ENDOCRINE
SYSTEM:
“In summary, evidence of several types
indicates that fluoride affects normal endocrine function or response;
the effects of the fluoride-induced changes vary in degree and
kind in different individuals. Fluoride is therefore an endocrine
disruptor in the broad sense of altering normal endocrine function
or response, although probably not in the sense of mimicking a
normal hormone. The mechanisms of action remain to be worked out
and appear to include both direct and indirect mechanisms, for
example, direct stimulation or inhibition of hormone secretion
by interference with second messenger function, indirect stimulation
or inhibition of hormone secretion by effects on things such as
calcium balance, and inhibition of peripheral enzymes that are
necessary for activation of the normal hormone.” p223
“Some of these [endocrine] effects are
associated with fluoride intake that is achievable at fluoride
concentrations in drinking water of 4 mg/L or less, especially
for young children or for individuals with high water intake.
Many of the effects could be considered subclinical effects, meaning
that they are not adverse health effects. However, recent work
on borderline hormonal imbalances and endocrine-disrupting chemicals
indicated that adverse health effects, or increased risks for
developing adverse effects, might be associated with seemingly
mild imbalances or perturbations in hormone concentrations. Further
research is needed to explore these possibilities.” p7
“Further effort is necessary to characterize
the direct and indirect mechanisms of fluoride’s action
on the endocrine system and the factors that determine the response,
if any, in a given individual.” p223
“The effects of fluoride on various aspects
of endocrine function should be examined further, particularly
with respect to a possible role in the development of several
diseases or mental states in the United States.” p224
FLUORIDE’S EFFECTS ON THE THYROID:
“several lines of information indicate
an effect of fluoride exposure on thyroid function.” p197
“it is difficult to predict exactly what
effects on thyroid function are likely at what concentration of
fluoride exposure and under what circumstances.” p197
“Fluoride exposure in humans is associated
with elevated TSH concentrations, increased goiter prevalence,
and altered T4 and T3 concentrations; similar effects on T4 and
T3 are reported in experimental animals..” p218
“In humans, effects on thyroid function
were associated with fluoride exposures of 0.05-0.13 mg/kg/day
when iodine intake was adequate and 0.01-0.03 mg/kg/day when iodine
intake was inadequate.” p218
“The recent decline in iodine intake in
the United States (CDC 2002d; Larsen et al. 2002) could contribute
to increased toxicity of fluoride for some individuals.”
p218
“Intake of nutrients such as calcium and
iodine often is not reported in studies of fluoride effects. The
effects of fluoride on thyroid function, for instance, might depend
on whether iodine intake is low, adequate, or high, or whether
dietary selenium is adequate.” p222
FLUORIDE’S EFFECTS ON THE PINEAL
GLAND:
“The single animal study of pineal function
indicates that fluoride exposure results in altered melatonin
production and altered timing of sexual maturity (Table 8-1).
Whether fluoride affects pineal function in humans remains to
be demonstrated. The two studies of menarcheal age in humans show
the possibility of earlier menarche in some individuals exposed
to fluoride, but no definitive statement can be made. Recent information
on the role of the pineal organ in humans suggests that any agent
that affects pineal function could affect human health in a variety
of ways, including effects on sexual maturation, calcium metabolism,
parathyroid function, postmenopausal osteoporosis, cancer, and
psychiatric disease.” p221-22
FLUORIDE’S EFFECTS ON INSULIN SECRETION/DIABETES:
“The conclusion from the available studies
is that sufficient fluoride exposure appears to bring about increases
in blood glucose or impaired glucose tolerance in some individuals
and to increase the severity of some types of diabetes. In general,
impaired glucose metabolism appears to be associated with serum
or plasma fluoride concentrations of about 0.1 mg/L or greater
in both animals and humans. In addition, diabetic individuals
will often have higher than normal water intake, and consequently,
will have higher than normal fluoride intake for a given concentration
of fluoride in drinking water. An estimated 16-20 million people
in the U.S. have diabetes mellitus; therefore, any role of fluoride
exposure in the development of impaired glucose metabolism or
diabetes is potentially significant.” p. 217
FLUORIDE’S EFFECTS ON THE IMMUNE
SYSTEM:
“Nevertheless, patients who live in either
an artificially fluoridated community or a community where the
drinking water naturally contains fluoride at 4 mg/L have all
accumulated fluoride in their skeletal systems and potentially
have very high fluoride concentrations in their bones. The bone
marrow is where immune cells develop and that could affect humoral
immunity and the production of antibodies to foreign chemicals.”
p249
“There is no question that fluoride can
affect the cells involved in providing immune responses. The question
is what proportion, if any, of the population consuming drinking
water containing fluoride at 4.0 mg/L on a regular basis will
have their immune systems compromised? Not a single epidemiologic
study has investigated whether fluoride in the drinking water
at 4 mg/L is associated with changes in immune function. Nor has
any study examined whether a person with an immunodeficiency disease
can tolerate fluoride ingestion from drinking water.” p250
“bone concentrates fluoride and the blood-borne
progenitors could be exposed to exceptionally high fluoride concentrations.
Thus, more research needs to be carried out before one can state
that drinking water containing fluoride at 4 mg/L has no effect
on the immune system.” p250
“it is important to consider subpopulations
that accumulate large concentrations of fluoride in their bones
(e.g., renal patients). When bone turnover occurs, the potential
exists for immune system cells and stem cells to be exposed to
concentrations of fluoride in the interstitial fluids of bone
that are higher than would be found in serum. From an immunologic
standpoint, individuals who are immunocompromised (e.g., AIDS,
transplant, and bone-marrow-replacement patients) could be at
greater risk of the immunologic effects of fluoride.” p
258
“Within 250 ?m of a site of resorption,
it is possible to encounter progenitor cells that give rise to
bone, blood, and fat. Thus, one must assume that these cells would
be exposed to high concentrations of fluoride. At this time, it
is not possible to predict what effect this exposure would have
on the functioning of skeletal elements, hematopoiesis, and adipose
formation.” p115
“It is paramount that careful biochemical
studies be conducted to determine what fluoride concentrations
occur in the bone and surrounding interstitial fluids from exposure
to fluoride in drinking water at up to 4 mg/L, because bone marrow
is the source of the progenitors that produce the immune system
cells.” p 259
“In addition, studies could be conducted
to determine what percentage of immunocompromised subjects have
adverse reactions when exposed to fluoride in the range of 1-4
mg/L in drinking water.” p259
FLUORIDE’S INTERACTIVE/SYNERGISTIC
EFFECTS (w/ IODINE, ALUMINUM, ETC):
“Intake of nutrients such as calcium and
iodine often is not reported in studies of fluoride effects. The
effects of fluoride on thyroid function, for instance, might depend
on whether iodine intake is low, adequate, or high, or whether
dietary selenium is adequate.” p222
“Better characterization of exposure to
fluoride is needed in epidemiology studies investigating potential
effects. Important exposure aspects of such studies would include
the following: collecting data on general dietary status and dietary
factors that could influence exposure or effects, such as calcium,
iodine, and aluminum intakes.” p72
“Available information now indicates a
role for aluminum in the interaction of fluoride on the second
messenger system; thus, differences in aluminum exposure might
explain some of the differences in response to fluoride exposures
among individuals and populations.” p222
“With the increasing prevalence of acid
rain, metal ions such as aluminum become more soluble and enter
our day-to-day environment; the opportunity for bioactive forms
of AlF to exist has increased in the past 100 years. Human exposure
to aluminofluorides can occur when a person ingests both a fluoride
source (e.g., fluoride in drinking water) and an aluminum source;
sources of human exposure to aluminum include drinking water,
tea, food residues, infant formula, aluminum-containing antacids
or medications, deodorants, cosmetics, and glassware.” p42
“Further research should include characterization
of both the exposure conditions and the physiological conditions
(for fluoride and for aluminum or beryllium) under which aluminofluoride
and beryllofluoride complexes can be expected to occur in humans
as well as the biological effects that could result.” p42
“Another possible explanation for increased
blood lead concentrations which has not been examined is the effect
of fluoride intake on calcium metabolism; a review by Goyer (1995)
indicates that higher blood and tissue concentrations of lead
occur when the diet is low in calcium. Increased fluoride exposure
appears to increase the dietary requirement for calcium (see Chapter
8); in addition, the substitution of tap-water based beverages
(e.g., soft drinks or reconstituted juices) for dairy products
would result in both increased fluoride intake and decreased calcium
intake.” p43
“[G]iven the expected presence of fluoride
ion (from any fluoridation source) and silica (native to the water)
in any fluoridated tap water, it would be useful to examine what
happens when that tap water is used to make acidic beverages or
products (commercially or in homes), especially fruit juice from
concentrate, tea, and soft drinks. Although neither Urbansky (2002)
nor Morris (2004) discusses such beverages, both indicate that
at pH < 5, SiF6 2- would be present, so it seems reasonable
to expect that some SiF6 2- would be present in acidic beverages
but not in the tap water used to prepare the beverages. Consumption
rates of these beverages are high for many people, and therefore
the possibility of biological effects of SiF62-, as opposed to
free fluoride ion, should be examined.” p44
FLUORIDE’S EFFECTS ON THE REPRODUCTIVE
SYSTEM:
“A few human studies suggested that high
concentrations of fluoride exposure might be associated with alterations
in reproductive hormones, effects on fertility, and developmental
outcomes, but design limitations make those studies insufficient
for risk evaluation.” p6
“the relationship between fertility and
fluoride requires additional study.” p161
FLUORIDE & DOWNS SYNDROME:
“The possible association of cytogenetic
effects with fluoride exposure suggests that Down’s syndrome
is a biologically plausible outcome of exposure.” p170
“A reanalysis of data on Down’s syndrome
and fluoride by Takahashi (1998) suggested a possible association
in children born to young mothers. A case-control study of the
incidence of Down’s syndrome in young women and fluoride
exposure would be useful for addressing that issue. However, it
may be particularly difficult to study the incidence of Down’s
syndrome today given increased fetal genetic testing and concerns
with confidentiality.” 172
FLUORIDE’S EFFECTS ON THE GASTROINTESTINAL
SYSTEM:
“The numerous fluoridation studies in the
past failed to rigorously test for changes in GI symptoms and
there are no studies on drinking water containing fluoride at
4 mg/L in which GI symptoms were carefully documented.”
p230
“GI effects appear to have been rarely
evaluated in the fluoride supplement studies that followed the
early ones in the 1950s and 1960s.” p231
“The table suggests that fluoride at 4
mg/L in the drinking water results in approximately 1% of the
population experiencing GI symptoms.” p231
“Whether fluoride activates G proteins
in the gut epithelium at very low doses (e.g., from fluoridated
water at 4.0 mg/L) and has significant effects on the gut cell
chemistry must be examined in biochemical studies.” p236
“There are a few case reports of GI upset
in subjects exposed to drinking water fluoridated at 1 mg/L. Those
effects were observed in only a small number of cases, which suggest
hypersensitivity. However, the available data are not robust enough
to determine whether that is the case.” p. 250
“Studies are needed to evaluate gastric
responses to fluoride from natural sources at concentrations up
to 4 mg/L and from artificial sources.” p. 258
FLUORIDE’S EFFECTS ON THE LIVER:
“It is possible that a lifetime ingestion
of 5-10 mg/day from drinking water containing 4 mg/L might turn
out to have long-term effects on the liver, and this should be
investigated in future epidemiologic studies.” p248
“The effect of low doses of fluoride on
kidney and liver enzyme functions in humans needs to be carefully
documented in communities exposed to different concentrations
of fluoride in drinking water.” p258
FLUORIDE’S EFFECTS ON THE KIDNEY:
“Human kidneys... concentrate fluoride
as much as 50-fold from plasma to urine. Portions of the renal
system may therefore be at higher risk of fluoride toxicity than
most soft tissues.” p236
“Early water fluoridation studies did not
carefully assess changes in renal function.” p236
“future studies should be directed toward
determining whether kidney stone formation is the most sensitive
end point on which to base the MCLG.” p247
“On the basis of studies carried out on
people living in regions where there is endemic fluorosis, ingestion
of fluoride at 12 mg per day would increase the risk for some
people to develop adverse renal effects.” p247
“The effect of low doses of fluoride on
kidney and liver enzyme functions in humans needs to be carefully
documented in communities exposed to different concentrations
of fluoride in drinking water.” p258
FLUORIDE & CANCER:
“Fluoride appears to have the potential
to initiate or promote cancers, particularly of the bone, but
the evidence to date is tentative and mixed (Tables 10-4 and 10-5).
As noted above, osteosarcoma is of particular concern as a potential
effect of fluoride because of (1) fluoride deposition in bone,
(2) the mitogenic effect of fluoride on bone cells, (3) animal
results described above, and (4) pre-1993 publication of some
positive, as well as negative, epidemiologic reports on associations
of fluoride exposure with osteosarcoma risk.“ p. 286
“Because fluoride stimulates osteoblast
proliferation, there is a theoretical risk that it might induce
a malignant change in the expanding cell population. This has
raised concerns that fluoride exposure might be an independent
risk factor for new osteosarcomas.” p109
“Osteosarcoma presents the greatest a priori
plausibility as a potential cancer target site because of fluoride’s
deposition in bone, the NTP animal study findings of borderline
increased osteosarcomas in male rats, and the known mitogenic
effect of fluoride on bone cells in culture (see Chapter 5). Principles
of cell biology indicate that stimuli for rapid cell division
increase the risks for some of the dividing cells to become malignant,
either by inducing random transforming events or by unmasking
malignant cells that previously were in nondividing states.”
p275
“Further research on a possible effect
of fluoride on bladder cancer risk should be conducted.”
p288
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