Open Letter to a
Dear Sir or
Bush has asked the Department of Environmental Protection
to respond to your letter to his office concerning the
use of fluoride in drinking water and impurities in
hydrofluorosilicic acid, which is used to add fluoride to
drinking water. We understand that your community is
discussing fluoridation. I hope the public discussion in
your community about this issue can provide you with the
information you need to make an informed decision in
support of fluoridation.
Our agency has
the responsibility to regulate water treatment chemicals,
such as hydrofluorosilicic acid. We require that all
water treatment chemicals be certified to be in
conformance with ASTM/NSF Standard 60 and AWWA Standard
B703. Chemicals that meet these standards are deemed safe
to be added to treat drinking water within specified
limits. When fluoride is added to drinking water it is
not a toxic or hazardous waste. It must meet strict
standards. It exceeds the food grade standards of the
In your letter,
you mentioned that hydrofluorosilicic acid contains
arsenic, mercury and lead. Your probable question is how
could this agency approve the use of a product with some
impurities and still protect public health? We would
answer that every material has some very small residue of
trace elements often considered impurities and that our
mission is to require that the public be protected from
levels of impurities that could cause some harm. The
levels of impurities found in hydrofluorosilicic acid are
very low and present no health risk to any consumers who
may drink water properly treated with this chemical.
we have evaluated the concentrations of six reported
impurities found in hydrofluorosilicic acid. Lead,
mercury and selenium are normally not present at all.
Iron and iodine are typically reported below levels
considered useful as a dietary supplement. The amount of
phosphorous found is usually insignificant to that amount
already added by your water system to your drinking water
to combat corrosion. Silver is typically reported at
0.0004 percent, or 4 parts per billion as an impurity.
The amount in drinking water would be less than 4 parts
per septillion (so small an amount that no lab could
measure it) at the usual dosage rate of fluoride
treatment for drinking water. The same is true for the
other chemicals you asked about. Think of the comparison
of one penny to the total national debt to visualize the
amount of impurities that may be in drinking water as a
result of fluoride treatment.
You also stated
in your letter that you were concerned that fluoride
treatment did not improve dental health for adults.
Evidence, gathered by the National Center for Disease
Control, now shows that fluoride treatment continues to
provide dental health benefits to all ages, perhaps not
as dramatic as for children, but still very important.
the possibility of accidents by your water treatment
plant in operating fluoridation treatment. They already
operate equipment that is much more complex to remove
ground water impurities from your drinking water. We are
confident that they can safely operate fluoridation
equipment. We will also require that they provide
safeguards such as day tanks and continuous monitoring
equipment to ensure that optimum dosages are maintained.
assured that we consider our mission to protect drinking
water our highest priority. We regularly review the
additives that drinking water systems use to ensure that
only safe chemicals are used.
Hoofnagle, P.E. Administrator
Drinking Water Program
letter from NSF International
International is an independent not-for-profit
organization. This organization develops standards
for chemicals and components. The State of Florida
requires all chemicals that are added to drinking water
and all components of a water system that come in contact
with drinking water be tested and certified as meeting
NSF International standards.
Florida Department of Health wrote to NSF International
and asked about the standards and testing programs for
chemicals used in fluoridation.
a copy of the letter NSF International sent to the Health