"In
regard to the use of fluosilicic acid as a source of fluoride for
fluoridation, this Agency regards such use as an ideal environmental
solution to a long-standing problem. By recovering by-product
fluosilicic acid from fertilizer manufacturing, water and air pollution
are minimized, and water utilities have a low-cost source of fluoride
available to them." This statement from the Environmental Protection
Agency's Office of Water makes the motivation for using SiF clear
(especially since the remainder of the letter refers only to a vague
"assessment" of SiF chemistry and standards for SiF "purity." (It needs
to be emphasized that contamination with SiF, while often charged by
critics, is not an essential factor in our research described below.)
"To
answer your first question on whether we have in our possession
empirical scientific data on the effects of fluosilicic acid or sodium
silicofluoride on health and behavior, our answer is no." This
statement by the Chief of the Treatment Technology Evaluation Branch of
the Water Supply and Water Resources Division of the US EPA is
explicitly based on confirmation by "our colleagues" at the EPA's
National Health and Environmental Effects Research Laboratory. Combined
with the 1983 letter from Hanmer to Russell, this letter is very strong
evidence that SiF was not subjected to biological tests of safety
justifying their use in over 90% of flouridated water in the US
Feldman, I, Morkin, D, and Hodge, HC. "The State of Fluoride in
Drinking Water," Journal of Dental Research, 36:2 (1957) 192-202.
The
first sentence of this article confirms that, at the time of their
approval in 1950, the chemical effects of SiF injected in a water
supply was unknown: "The widespread use of sodium silicofluoride in
fluoridating drinking water has made it important to determine the
state of the fluoride in such water, specifically, how much is fluoride
ion, how much, if any, is unchanged solicofluoride, how much is
fluoride bound to other ions. If all or nearly all of the fluoride is
the F-, the great body of information about the biologic
effects of fluorides can be brought forward as a guarantee of safety.
If considerable amounts of silicofluoride remain, a question can
legitimately be raised since comparatively little work has been done on
the biologic effects of silicofluorides." (192). Despite the author'
claim to present "experimental results" (in 1957), their analysis was
essentially a theoretical extrapolation that didn't provide a direct
test of chemical and biochemical effects under conditions approximating
actual usage. Moreover, the claim of safety is limited to the extent of
dissociation of fluoride (i.,e., separation of fluoride ion from the
rest of the molecule), ignoring issues of biological effects of
"residual species" of silicates such as those found by Westendorf (see
below).
McClure, F.J., "Availability of Fluorine in Sodium Fluoride vs.
Sodium Fluosilicate." US Public Health Service Report 65 (1950), pp.
1175-1186; reprinted in Fluoride Drinking Waters (Washington: US Public
Health Service, 1962), 825: 527-532.
"In dilute aqueous
solutions the hydrolysis of these two fluorine salts yielding fluoride
ions is comparatively simple in the case of the sodium fluoride, which
is practically completely ionized, but quite complex and somewhat
obscure in the case of sodium fluosilicate." Following the specific
chemical reactions "postulated" or suggested by chemists, McClure
considers "the rate of retention and paths of excretion of fluorine"
when ingested from these compounds, beginning by summarizing data in a
1935 study by Kick et al., who found that "there was no difference
between sodium fluosilicate and sodium fluoride as regards the ultimate
percent of fluorine retained in the rat's body, i.e., the percent
fluorine balance in the above data. There were some differences,
however, in the paths of excretion, i.e., in urine or feces." McClure's
replication confirms data on percentage of fluorine retained but does
not challenge Kick's finding of a difference in pathways of excretion
(which is consistent with hypothesis of different biochemical
side-effects from "residual species of silicate found by Westendorf).
Crosby, N.T. (1969). "Equilibria of Fluosilicate Solutions with
Special Reference to the Fluoridation of Public Water Supplies," J.
Appl. Chem 19: 100-102.
Silicofluorides are unlikely to
dissociate completely under water plant conditions, producing only free
fluoride and silicic acid without side reactions (as was assumed when
SiF was originally approved) because the silicofluoride moiety [SiF6]2- can react with Al(OH)3
to produce a number of derivative compounds. Moreover, silicofluoride
residues may reassociate either within the stomach or in food
preparation.
Busey, R. H. (1980) "Fluosilicate Equilibria in Sodium Chloride Solutions from 0 to 60^ C" Inorg. Chem 19: 758-761.
Knappwost A, Westendorf J, "Hemmung von Cholinesterasen durch
Fluorokomplexe des Siliciums und des Eisens [Inhibition of
cholinesterasse by fluorocomplexes of silicon and iron]"
Naturwissenchaften 61 (1974) 275.
Experimental
evidence contradicting the assumption that SiF and NaF are equivalent
sources of free fluoride when used for water fluoridation. Due to
incomplete dissociation of SiF compounds into their component elements,
there is a "residual complex" of silicate remaining in water that,
while not definitively identified, has effects different from those
when sodium fluoride is added to water. The "residual complex" from SiF
has a biological effect on acetylcholinesterase inhibition, which can
be dangerous because acetylcholinesterase controls the action of
acetylcholine (ACh), a neurotransmitter that plays an important role in
memory and other brain functions. Other neuroscientists have associated
the disturbances of normal brain chemistry by acetylcholinesterase
inhibition with such important changes in behavior as increased
aggression (for findings of this effect where silicofluorides are used
in the U.S., see below). These demonstrations of differences between
the biochemistry and behavioral effects of sodium fluoride and the
silicofluorides have never been challenged with experimental data and
were never considered by the governmental agencies responsible for the
safety of American public water supplies.
At a meeting in January 2001: "Several fluoride
chemistry related research needs were identified including: (1)
accurate and precise values for the stability constants of mixed
fluorohydroxo complexes with aluminum (III), iron (III) and other metal
cations likely to be found under drinking water conditions and (2) a
kinetic model for the dissociation and hydroloysis (sic) of
fluosilicates and stepwise equilibrium constants for the partial
hydrolyisis products. As a result of these discussions, ORD is
exploring options to initiate research in the identified research
areas."
NOTE: The experimental findings by Westendorf are essential to
any consideration of the safety of using silicofluorides instead of
sodium fluoride (and show that continued discussion of "fluoridation"
without reference to the chemicals used for this purpose is
irresponsible). The other letters and articles in this section offer
confirmation from that, at the time of their approval in 1950, the
precise chemistry of silicofluorides was not fully known and their
biological or behavioral effects had not been empirically studied.
Moreover, when the safety standards for the "fluoride" were considered
by a special committee convened by the Surgeon General C. Everett Koop
in 1983, not only was there no consideration of silicofluorides but the
definition of "harmful" effects was limited to death from disease. As a
result, in addition to Westendorf's experiments, the principal evidence
on effects of adding SiF to public water (research below) needs to be
considered in the light of behavioral effects of toxic chemicals like
lead.
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Consistent with evidence that
violent criminals have higher than average blood levels of lead and
manganese, multivariate analysis correlates industrial pollution with
lead and manganese pollution (as measured by the EPA's Toxic Release
Inventory) with violent crime data from all 3141 US counties. The
effects of heavy metals on neurotransmitter function and behavior are
thus linked to important policy issues.
Masters, Roger D., with Baldwin Way, Brian T. Hone, David J.
Grelotti, David Gonzalez, and David Jones (1998) "Neurotoxicity and
Violence," Vermont Law Review, 22: 358-382.
Legal
implications of the evidence linking toxins and crime (with data
analyzing the association of violent crime rates with pollution with
heavy metals). The absence of comparable effects on Property Crime
(which is less likely to be associated with loss of impulse control due
to changes in brain chemistry) reinforces these findings for Violent
Crime.
Masters, R. D. (2002). "MacLean's Evolutionary Neuroethology:
Environmental Pollution, Brain Chemistry, and Violent Crime," Gerald A.
Corey Jr. & Russell Gardner Jr., eds. The Evolutionary
Neuroethology of Paul MacLean (Westport: Praeger), pp. 275-296 (Ch. 15).
Survey
of research on neurotoxicity, brain chemistry and behavior, including
evidence of the role of lead and other heavy metal pollution and crime
(as demonstrated by individual data, neurochemistry, and both
geographic and longitudinal data) as well as survey of data linking
silicofluorides to enhanced lead uptake. First presentation of findings
on the extremely high correlation (r=.90) between gallons of leaded
gasoline sold and the crime rates sixteen years later, confirming
special vulnerability of pregnant mothers and newborns to lead toxicity.
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Masters, R. and Coplan, M. (1999a) "Water Treatment with
Silicofluorides and Lead Toxicity," International Journal of
Environmental Studies, 56: 435-49.
First published analysis
of data linking silicofluoride treatment of public water supplies with
higher uptake of lead, focused on survey of children's blood lead in
Massachusetts (by town).
Masters, R. and Coplan, M. (1999b) "A Dynamic, Multifactorial Model
of Alchohol, Drug Abuse, and Crime: Linking Neuroscience and Behavior
to Toxicology," Social Science Information, 38: 591-624.
Articulation
of the linkages between neurotoxicity, brain chemistry, environmental
pollution, and behavior (with focus on substance abuse and crime),
using data from National Institute of Justice study of drug use in over
30,000 criminal offenders at time of arrest). Data show that where SiF
is in use, criminals are more likely to consume alchohol, and to have
used cocaine at time of arrest (as well as confirming that such
communities have significantly higher violent crime rates).
Masters, R.D., Coplan, M. J., Hone, B. T., and Dykes, J. E. (2000).
"Association of Silicofluoride Treated Water with Elevated Blood Lead,"
Neurotoxicology 21: 101-1100.
Follow-up epidemiological
study of the association between SiF treated water and enhanced child
blood lead. This statistical study of 151,225 venous blood lead tests
taken from children ages 0-6, living in 105 communities with
populations from 15,000 to 75,000 in New York state, shows for every
age and racial group a significant association between SiF usage and
elevated blood lead.
Analysis of evidence
of neurotransmitter dysfunction due to toxins associated with increased
rates of violent crime, with extensive discussion of silicofluoride
neurotoxicity as an important instance.
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Masters, Roger D. (2001), "Biology and Politics: Linking Nature and
Nurture" in Nelson W. Polsby, ed., Annual Review of Political Science,
vol. 4, pp. 45-369.
A survey of the scope of the emerging
subfield called "biopolitics," reflecting the activities of the
membership of the Association for Politics and the Life Sciences. Four
areas are discussed in some detail: 1) genetics and health; 2) toxins
and behavior (including hyperactivity, depression, and violent crime);
3) the specific case of SiF in water treatment and its effect in
enhancing lead uptake; and 4) biopolitics and political theory. Note:
one-time e-print available here.
Myron J. Coplan and Roger Masters. 2001. "Guest Editorial:
Silicofluorides and fluoridation," Fluoride: Quarterly Journal of hte
International Society for Fluoride Research, 34: 161-220.
Coplan, M. J. and Masters, R. D. (1999). "Is Silicofluoride Safe?
Comments Re EPA Response to Rep. Clavert's Inquiry" Submission to
Representative Kenneth Calvert, Subcommittee on Energy and Science,
Committee on Science, U.S. House of Representatives (August 12, 1999).
Analysis
and rejoinder to letter dated 12 June 1999 from J. Charles Fox,
Assistant Adminstrator, EPA, to Hon. Kenneth Clavert, U.S. House of
Representative, commenting on errors and omissions in a "Question and
Answer" statement and "Fluorosilicate Fact Sheet" enclosed by Mr. Fox.
this document contains a preliminary review of scientific data on the
differences between sodium fluoride (NaF) and the silicofluorides (H2SiF6 and Na2SiF6), with an emphasis on the complex production process and chemical interactions of the latter compounds.
Masters, R. D. and Coplan, M. J., with Hone, B.T., Grelotti, D.J.,
Gonzalez, D. and Jones, D. (in press). "Brain Biochemistry and the
Violence Epidemic: Toward a 'Win-Win' Strategy for Reducing Crime," in
Stuart Nagel, ed., Super-Optimizing Examples Across Public Policy
Problems (NOVA Science Publishers) (in press).
Review of the
evidence linking neurotoxicity and crime, using data from both
county-level study (correlating EPA Toxic Release Inventory with FBI
crime reports) and Massachusetts data on silicofluorides and lead
uptake.
Masters, Roger D. "The Gap between Neuroscience and Public Policy:
Case Studies of Environmental Toxins, Brain Chemistry, and Behavior,"
APSA STEP Newsletter (in press, Fall 2005).
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Masters, R. D. and Coplan, M. J. (1998) "Silicofluoride Usage and
Lead Uptake," Presentation to XXIInd Conference of the International
Society for Fluoride Research, Bellingham, Washington, August 24-27,
1998.
Report on findings of elevated blood lead associated
with communities using silicofluoride, based on sample of over 250,000
children in Massachusetts (see Masters and Coplan, 1999a), with special
emphasis on greater severity of harmful effects in communities with a
higher percentage of black residents.
Masters, R. D. (1999a). "Poisoning the Well: Neurotoxic Metals,
Water Treatment and Human Behavior," Plenary address to Annual
Conference of the Association for Politics and the Life Sciences," Four
Seasons Hotel, Atlanta, GA (September 2, 1999).
Review of
evidence linking heavy metal pollution with substance abuse and crime,
including presentation of data linking ban on sales of leaded gasoline
with decline in crime 16 years later. Summary of geographical data
analyses contradicting the "null hypothesis" that there is no
difference in the effects of sodium fluoride and the silicofluorides.
Coplan, M. J., Masters, R. D., and Hone, B. (1999b) "Silicofluoride
Usage, Tooth Decay and Children's Blood Lead," Poster presentation to
Confernence on "Environmental Influences on Children: Brain,
Development and Behavior, New York Academy of Medicine, Mt. Sinai
Hospital, New York, May 24-25, 1999.
Preliminary report on
data from analysis of national sample of over 4,000 children in NHANES
III, showing that while water fluoridation is associated with a
significant increase in children's blood lead (with especially strong
effects among minority children), data on tooth decay from the same
survey show limited benefits that are no longer evident among those
aged 15-17.
Coplan, M. J., Masters, R. D., and Hone, B. (1999c) "Association of
Silicofluoride Treated Water with Elevated Blood Lead," Poster
Presentation to 17th International Neurotoxicology Conference, Little Rock, AR, October 17, 1999.
Preliminary
report on date from analysis of sample of blood lead testing of over
150,000 children in New York State communities of 15,000 to 75,000
population. Once again, average blood lead levels were significantly
higher (p < .0001) in communitites using SiF in water treatment than
in those with unfluoridated water. The effect was found independently
in every age group for three ethnic subsamples.
Masters, Roger D. (2002) "Science, Bureaucracy and Public Policy:
Can Scientific Inquiry Prevail Over Entrenched Institutional
Self-Interest?" presentation at the annual meeting of hte Association
for Politics and the Life Sciences, Montreal, Que. (August 19-23, 2002).
Analysis
of bureaucratic opposition to reconsideration of public policy
decisions challenged by new data on SiF chemistry and its effects on
human biology and behavior.
Masters, Roger D. (2004) "The Hidden Handicap: Lead, Brain
Chemistry, and Educational Failure," Paper presented to 2004 Annual
Meeting of the American Political Science Association, Chicago, IL.,
Sept. 3, 2004.
Evidence linking higher rates of children iwth over 10-9g/dL
of blood lead iwth lower community average scores in Massachusetts'
standardized tests in seven different subjects and grade. These
findings, showing significant effects controlling for a wide range of
socio-economic and demographic factors, confirm earlier research by
linking toxicity with lower scores on types of tests used in programs
like "No Child Left Behind."
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