This transcript is from a video filmed by Fluoride
Action Network
http://www.fluoridealert.org/
August 12, 2003
Presentation by Joyce Donahue,
PhD
Toxicologist, Office of Science and Techology,
US Environmental Protection Agency, Office of Drinking Water
to
National Academies' National Research Council Committee:
Toxicologic Risk of Fluoride in Drinking Water
[BEST-K-02-05-A]
(Also called, Committee on Fluoride in Drinking Water)
[First Slide]
US
EPA Drinking Water Regulations for Fluoride
Joyce
Donahue, Ph.D.
Health
and Ecological Criteria
Office
of Drinking Water
|
Good Morning. I am Joyce Donahue and I work as a toxicologist at
the Office of Science and Techology in EPA Office of Water. I'd
like to start these remarks by stating that I joined EPA in 1996,
which is ten years after this fluoride regulation was established,
and so I don't have first-hand knowledge of many of the discussions
that went on at the time the regulation was established.
I am going to talk to you today just about that regulation, what
they are, the utility's responsibilities of the various water systems
in enforcement of regulation and finding other information for your
clients and then let you see some of the reasons that we made the
recommendation for this review of the data. It is after all ten
years since the 1993 publication and in that time period there have
been a number of new studies that we felt we would like to have,
a panel such as yours, evaluate and give us recommendations.
Next Slide.
Drinking
Water Regulations*
•
Primary Drinking Water Regulations
•
Maximum Contaminant Level Goal (MCLG)
•
Maximum Contaminant Level (MCL)
•
Secondary Drinking Water Regulations
•
Secondary MCL
•
Not all information on this slide is included due to filming. |
EPA publishes drinking water regulations that have a variety of
characeristics. The primary drinking water regulations are those
that the utiliues must meet. And they come in the MCLG, which is
the goal, and the non-enforceable value which does provide an adequate
margin of safety for the public, and the MCL, which is the enforceable
value. The MCL will be equal to the MCLG if it is technically feasible.
If it is not technically feasible then there will be a difference
between the goal and the actual regulatory value. In the case of
fluoride, the two values are the same and they are 4 milligrams
per liter. EPA also establishes what we call secondary drinking
water regulations and gives a secondary maximum contaminant level.
They are not enforceable values, although the state have the option
of making them their state values. They deal with aesthetic and
cosmetic effects. For fluoride there is a secondry MCL and its based
on the cosmetic effect for dental fluorosis.
Next Slide
Fluoride
Regulations
FR (63) - April 2, 1986
•
MCL/MCLG = 4 mg/L
•
To protect against skeletal fluorosis
•
SMCL = 2 mg/L
•
To protect against dental fluorosis
|
As I just mentioned the MCL, MCLG for fluoride is 4 milligrams
per liter and its goal, or its purpose, is to protect against crippling
skeletal fluorosis. The secondary MCL is 2 milligrams per liter
and its objective is to protect against dental fluorosis.
Next slide.
Skeletal
fluorosis
•
Skeletal changes consisting of combined osteoschlerosis
and osteomalacia.
•
Osteoschlerosis: the hardening or abnormal hardening
of the bone
•
Osteomalacia: marked softening of the bone due to impaired
mineralization due to impaired mineralization and excess
accumulation of osteoide
|
According to the medical dictionary, skeletal fluorosis is described
as skeletal changes consisting of combined osteoschlerosis and osteomalacia.
Osteoschlerosis is hardening or abnormal density of the bone and
osteomalacia is a marked softening of the bone due to impaired mineralization
and excess accumulation of osteoide. Now this was not actually the
endpoint that was used as the basis of regulation. It went a step
further and it targeted crippling skeletal fluorosis. Next slide.
Crippling skeletal fluorosis is described as a condition that causes
limitation of joint movement, calcification of the ligaments, crippling
deformities, muscle pain and tenderness, and muscle wasting.
The MCLG derivation is given in the next slide.
MCLG
Derivation
MCLG
= 20 mg/day (2 L/day)
= 10 mg/L (2.5) = 4 mg/L
Where
20
mg/day = LOAEL for skeletal fluorosis
2
L/day = Adult drinkng water intake
2.5
= Safety factor
|
As described in the Federal Register of 1986 that established
the MCLG for fluoride the value was derived by taking 20 milligrams
per day, which is identified as a Lowest Observable Adverse Effect
Level, from case studes in limited number of kid studies of crippling
clinical skeletal fluorosis. Since we assume that the population
consumes two liters of water per day, this value of 20 milligrams
per day was divided by two liters, and then an uncertainty factor,
or as it was called at that time, a safety factor, of 2.5 was applied
to get the MCL.
Because these are case study cases, was determined after the effect
that the approximate intake of fluoride that led to this condition
was 20 milligrams per day and that was based, as far as I can tell,
on analysis of the water consumed by these individuals. But the
period of consumption was considered to be twenty years. Therefore,
since it was retrospective, you have to look at that value as being
an approximate, rather than a very precise value. It was also the
first regulation established by EPA.
QUESTION FROM COMMITTEE MEMBER:
Can we ask questions during this.
DR. DONAHUE:
I'm fine.
COMMITTEE MEMBER:
Was the 2.5 the safety factor?
DR. DONAHUE:
Right
COMMITTEE MEMBER:
The derivation of that - where did that come from? Do you know?
DR. DONAHUE:
No. And if we were to do it today, we now use uncertainty factors
rather than safety factors. And our uncertainty factors today are
1, 3 and 10 for dividing conditions. So, the 2.5 is unusual, it
is not without precedent. Copper is another one of my minerals and
in that one we use two. So there are a few cases where the uncertainty
factors don't follow our normal pattern 1, 3 and 10. Any others?
Dental
Fluorosis
•
Normal Tooth: smooth, glossy, and creamy enamel survace.
•
Dental Fluorosis: Mottled enamel of the teeth
* Mild: White opaque areas in the enamel of the teeth
•
Modewrate: Some brown stain visible along the upper
opcities
•
Severe: Yellow to brown staining discoloration; pitting
and cracking of the teeth.
|
Because of the acknowledged ability of fluoride to also affect
calcification of the teeth, or the structure of the teeth, there
was a secondary MCL that was also established in 1986. Next slide.
It was to prevent dental fluorosis. Now, normal tooth structure
is supposed to be smooth, glossy with creamy enamel surface. Dental
fluorisis is described as mottled enamel of the teeth and it comes
in a variety of degrees of seriousness. Mild fluorosis causes white
opaque areas in the enamel. When it becomes moderate you begin to
see some brown staining around those opaque areas. And when it's
severe, the teeth have yellow to brown discoloration, that have
pits and in very highest degrees of serverity there is actual cracking
of the teeth.
In targeting or developing the secondary MCL it was objectionable
dental fluorosis that was targeted.
Next slide.
Objectionable
Dental Fluorosis
•
Moderate or severe dental fluorosis
•
Visible dark stains and pitting of teeth
|
Now objectionable dental fluorosis is defined as moderate or severe
and it iconsisted of visible dark stain and pitting of the teeth.
[Next slide]
SMCL
Derivation
•
Utilized data on the incidence of moderate and severe
dental fluorosis
•
At 2 mg/L the incidence of modert dental fluorosis ranged
from 0 to 15%
•
There was a distinct increase in incidence of moderate
dental fluorosis at concentrtion above 1.9 mg/L; severe
dental fluorosis at levels above 2.5 mg/L
|
The SMCL was also derived from epidemilogical or type of case study
data, and as described, and I recognize this little discrepancy
in this, at 2 mg/L the incidence of moderate dental fluorosis ranged
from 0 to 15 percent in the various studies. And there was a distinct
increase in the incidence of moderate dental fluorosis at concentrations
above 1.9 mg/L. Severe dental fluorosis, a distinct increase grew
at levels above 2.5 mg/L. And at least in the record that's in the
Federal Register you have some discussion of the variety of studies,
but its again not terribly precise. You are trying to pool these
individual case studies where people went to dental fluorosis population.
[Next slide]
Support
for EPA Regulatory Approach
Public Health Service (1982)
•
The optimum concentration of fluroide is best defined
as that concentration which provided the highest level
of protection against dental caries with a minimal prevalence
of clinically observable dental fluorosis.
•
No evidence should shows that fluoride in public water
suppplies in the US has any adverse effect on dental health
as measured by loss of function and tooth mortality.
•
To minimize the occurrence of undesirable cosmetic effects,
maintain the upper limit of fluoride in drinking water
should at two times the recommended optimum concentration.
|
Back during the development of the regulations EPA at several instances
went to Public Health Service and asked for their input on deciding
whether or not the basis of the regulation should be the dental
fluorosis or the skeletal fluorosis. And the Public Health Service
in 1982 gave the second of two reportsthat they issued and they
said the following:
The optimum concentration of fluroide is best defined as that
concentration which provided the highest level of protection against
dental caries with a minimal prevalence of clinically observable
dental fluorosis.
No evidence should shows that fluoride in public water suppplies
in the US has any adverse effect on dental health as measured
by loss of function and tooth mortality.
And they recommended that to minimize the occurrence of undesirable
cosmetic effects, the upper limit of fluoride in drinking water
should be maintained at two times the recommended optimum concentration.
Now because of this recommendation EPA made the unusual decision
to separate the dental fluorosis from the skeletal fluorosis and
give a secondary MCL that had requirements for public notification
because the vulnerability of the tooth to dental fluorosis occurs
during the period of time from tooth formation from eight or nine
years of age, depending upon the source that you look at. So there
are public notice requirements that are part of the law.
[Next slide]
Public
Notification Requirements
•
Consumer Confidence Report
•
Sent by Utility once a year
•
Reports concentrations of fluoride monitored in water
during the year
•
Public Notification of SMCL exceedance
•
Sent by Utility if the 2 mg/L SMCL is exceeded
|
The latter of the two is the Consumer Confidence Report which
now must go out from every utility to every customer each year.
And it reports the concentrations that are monitored of fluoride
and all the other contaminants during the year. There is the requirement
for a failure or receipt of the secondary MCL that has been in effect
since 1986 when the requlation was passed.
Next slide
Consumer
Confidence Language
•
People who drink water with concentrations in excess of
the MCL for many years could experience pain and tenderness
in their bones.
•
Children under the age of nine with concentrations greater
than one half ot he MCL could experience mottling of teeth.
|
The Consumer
Confidence language which was published in draft form proposal,
and made final a few years ago, tells people that people
who drink water with concentrations in excess of the MCL for many
years could experience pain and tenderness of the bones. All of
these notices are short sentences because we are trying to maximize
the message in as few words as possible. And then it goes on to
say, children under the age of nine who drink water with concentrations
greater than one half of the MCL could experience mottling of teeth.
And that, as I said, goes clearly goes to the issue for the person
in public certified drinking water utility if their is an exceedance
of the SMCL or the MCL.
[Next slide]
SCML
Violation Notice
•
Explains dental fluorosis
•
Identifies concentration found in drinking water
•
Suggests use of alternate drinking water source for children
under age nine
•
Recommends dental consultation about use of fluoride-containing
products
•
Provides contact information for utility
•
Provides contact information for identifying home treatment
units that will remove fluoride.
|
The special secondary MCL violation of this is much longer and
so I excerpted and tried to point out to you the main points that
it conveys. And we recently made a change to this. So this is slightly
different from the ______[UNCLEAR]. It explains what dental fluorosis
is. It identifies for the consumer the concentration that was found
in your drinking water. It suggests the use of alternate drinking
water sources for children under nine. This is the new part. I have
four children and so I thought if I tell them that I can drink water
______[UNCLEAR]. So, it recommends dental consultation about the
use of fluoride-containing dental products. Because use of these
products has increased since 1986. It provides contact information
for the utility to let them know how they can contact the drinking
water system. And it also provides contact information for identifying
home treatment units that will remove fluoride from the drinking
water. And each system which contains at any time a reading for
the concentration of fluoride greater than 2 mg/L is required to
send this to area health authorities.
Next slide.
NAS
Review of Fluoride (1993)
•
Published: Health Effects of Ingested Fluoride
•
Reviewed health effects and occurrence data
•
Concluded EPA's MCL appropriate as interim standard
•
Made research recommendations on
•
Fluoride intake
• Dental fluorosis
• Bone strength and fractures
• Carcinogenicty
•
Recommended the examination of the standard when research
results become available.
|
Over the course of time since 1986, EPA has looked at fluoride
several times. Dr. Doull mentioned the first review done by the
National Academy in 1993. And in that review, the book Health
Effects of Ingested Fluoride, and that book reviewed
the health effects and occurrence data for fluoride at that time.
The conslusion was that EPA's MCL was appropriate as an interim
standard. So it's obvious
that the Academy intended us to go back and look at it again after
we had additional data. They made specific research recommendations
about measuring fluoride intake, the totality of fluoride intake,
because the MCL just deals with the fluoride from water. It does
not deal with fluoride from other sources. It made recommendations
about going back and doing additional studies about the incidence
of dental fluorosis in this country because, as we know, fluoride
has been continually added to other personal care products, like
mouthwashes and toothpaste for years. It suggested additional studies
on bone strength and fractures and it also asks for additional studies
on carcinogenicity. It was recommended that the study be re-examined
when the research results become available.So you're back here.
[Next slide]
EPA
Review of Drinking Water Regulations - 2002
•
Reviewed all Drinking Water Regulations established before
1996
•
Identified new health effect studies published after the
1993 NAS review
•
Examined monitoring data
•
Recommended an independent review of the data
•
Requested that NAS/NRC update their 1993 assessment
|
The 1996 Safe Drinking Water Act made a requirement for EPA to
relook at all of its drinking water regulations every six years.
So we completed a first review in 2002. And we did look at the new
toxicity data for 68 various contaminants, one of them was fluoride.
We did literature searches for new information on all 68. While
we examined the monitoring data from the ulilities, because unlike
1986, we had systems that were measuring fluoride on a quarterly
basis, so we really had good data from various sytstems across the
United States about how much fluoride was there. On the basis of
what we saw in our literature search and on the basis of what we
saw in our monitoring data we had recommended a independent view
of the new information on fluoride and we requested that you all
come here and update what was not in 1993.
QUESTION FROM COMMITTEE MEMBER:
Does the request for the update by NAS imply that EPA has concluded
that the research recommended in 1993 has been conducted sufficiently?
DR. DONAHUE:
Certainly there is more than there was then. Are all of the data
gaps filled, I would say no. But I did a review of the literature
searches rather than a review of the actual published papers. I
have looked at many of the published papers, but certaintly not
all of them. But there are things that were nøt available
in 1993, I can attest to that.
Next slide.
Recent
Data for NAS Consideration
•
First Nutritional Guidelines established by the Institute
of Medicine (IOM) in 1997
•
Adequate value
•
Children - 0.1 to 2 mg/day
• Adults - 3 to 4 mg/day
•
Increaased exposure to fluoride through personal care
products and dental treatments.
|
What are some of the things -this is not encyclopediac- what are
some of the things, that I'll call to your attention, that we know
from the literature review. I've worked as a toxicologist for the
Environmental Protection Agency, but it was many years ago that
a registered dietician and I ______[UNCLEAR]. So it was certainly
very much in mind - scope - that I came up with a RD that the National
Academy of Sciences Institute of Medicine for the first time in
1997 change their policies somewhat about calling fluoride a benefical
substance to actually calling it a nutrient
[see note at bottom] and establish what they call an adequate
intake value for it of .1 to 2 milligrams per day for children and
3 to 4 milligrams per day for adults. Also, the literature that
I've been looking at -and the literature that we found in our literature
search- indicates that there is increased exposure to fluoride through
personal care dental products and dental treatment. More dentists
are giving fluoride treatments to their patients. Back in '86, as
I recall, we had it in toothpaste but we didn't have it in mouthwashes,
we didn't have it in some of the other sources that we now have
it. So we felt that there was definitely a time to look at the total
exposure issue.
Next slide.
Recent
Data for NAS Consideration (contd.)
•
Possible increase in the incidence of dental fluorosis.
•
Topical versus systemic impact of fluoride on dental caries.
•
Critical exposure windows for dental fluorosis during
development.
|
Papers that I've seen indicate that there is a possible, and maybe
probable, increase in the incidence of dental fluorosis. But the
majority of the studies that I have read indicate that it can be
traced more to those personal care products rather than to fluoride
that we have in drinking water. There is a question about whether
or not the effect of fluoride on dental cavities is really just
topical or systemic. And I've seen that in the literature as well.
So that's another issue that you perhaps should consider. When we
revised the public notification language the question about how
quickly after the exceedance should we get the notice out came up.
And we started looking at the literature about what are the critical
windows this occurs if one is going to get cosmetic dental fluorois.
And there is not a lot of data on that but there are a couple of
studies that we looked when we were revising the revised public
notification notice. And I think those are things one should look
at.
Next slide
Recent
Data for NAS Consideration (contd.)
•
New data from clinical trials on the use of fluoride in
the treatment of osteoporosis.
•
Reproductive and developmental studies of fluoride.
•
Effects of fluoride on the brain.
|
Back in '93 there was the beginning of the process of using sodium
fluoride, other fluoride compounds, in treatment of osteoporosis.
That data base has expanded. And some of the studies that I have
reviewed the abstracts indicate that not all bone disease, that
some bones effected by that fluoride treatment in a different fashion
than others. Those studies are very good for hazard identification,
they're more problematic for dose response because we really don't
have regulated doses, we have the pharmacological dose that was
given. But its another body of literature which has expanded since
the '93 report. FDA has issued a study of developmental effects
of fluoride and another study of the reproductive effects of fluoride
which were not available at the time of the last study. And so that's
another thing that one should look at.
QUESTION FROM COMMITTEE MEMBER:
Is the comment of the magnitude of fluorosis used in this study
DR. DONAHUE:
Not off the top of my head. When I was younger I could have done
that. But now I can't remember those things.
And then there is a series of studies that are both a combination
of studies that do have doses but also some epidemiological data
that suggest that there may be effects of fluoride on the brain
directly or indirectly and that was another group of studies that
we have looked at. So we asked you to come here.
[Next slide]
Charge
to NAS
•
Review new toxicologic, epidemiological and clinical data.
•
Examine exposure data on orally ingested fluoride from
water and other sources.
•
Examine the scientific and technical basis for the EPA
MCL and SMCL.
•
Advise EPA on the adequacy of its MCL and SMCL to protect
childlren and others from adverse effects.
•
Identify data gaps and make research recommendations.
|
And the charge that we gave, again this is abbreviated, was that
we asked for a review of the new top of the line epidemiological
and clincical data on fluoride, and the effects of fluoride. We
asked that you examine the exposure data on orally ingested fluoride
from moderate and other sources to determine whether or not the
basic assumption of the original pool that if it took 20 milligrams
per day, all of it in moderate, to cause crippling skeletal fluorosis.
Should we still have a hundred per cent of relative source contribution
to fluoride. We asked for you to evaluate the scientific and technical
basis for the EPA MCL and secondary MCL. And advise EPA on the adequacy
of these values to protect children and others from adverse effects.
And, as before, there are still data gaps, we ask you to identify
data gaps and to make research recommendations. So, that's what
brought you all here and I'll be happy to answer any questions,
if I can answer, about the regulation itself and about how we got
from 1986 to today.
QUESTION FROM COMMITTEE MEMBER:
If you could, the charge sounds to me like you want us to examine
adverse effects and safety issues as opposed to benefits. In other
words, risks as opposed to benefits. Is that right? [Or, naturally
occuring incidence - UNCLEAR].
DR. DONAHUE:
Because EPA's regulations exist to prevent too much from being injury
to us and because since we are at specifically at what it says,
EPA are not to make any recommendations that cause the initiative
of anything to drinking water purposes other than disinfection and
disease control. I think we are asking you to look at the adverse
more than the beneficial. The Institute of Medicine, in terms of
their nutritional value, has examined the beneficial side of it.
COMMITTEE MEMBER:
As a follow up to that, recent data on topical versus systemic impact
on fluoride. Given what you just said about our scope, I don't understand
how that really applies.
DR. DONAHUE:
Right. Right.
NRC COMMITTEE MEMBER:
So could you clarify that for us.
DR. DONAHUE:
I can just say that when I sat down to put this together and I started
thinking about the issues that had come before me as I answer letters
from people who write in about fluoride, that was one of the issues
that I saw. And you're right. In terms of beneficial effect it doesn't
fit - UNCLEAR.
COMMITTEE MEMBER:
[Question inaudible]
DR. DONAHUE:
Again, I am going to refer to people who write letters to EPA. Much
of this came from letters. And they are concerned about people who
have kidney problems, and don't excrete the fluoride. Also consideration
about people who have diabetes and that is reflected in kidney problems
in [WORD UNCLEAR]. We also get letters occaisionally from people
who say they have allergeic reactions to it, so that's another question
we get asked.
NRC COMMITTEE MEMBER:
[Question inaudible]
DR. DONAHUE:
We have a mandate to protect all sensitive populations that we can
protect through the drinking water regulations. In some cases the
protection has to be through the medical community, for example
the sodium. We have a requirement the medical community to be notified
what the sodium levels are so that they can also notify their patients.
COMMITTEE MEMBER:
It's been 72 years since the MCL and the SMCL were developed. Can
you tell us how strongly this additional [UNCLEAR] and if we need
help in determining which studies were used and how they were -
you said they were set in a rather certain process
DR. DONAHUE:
I've been told that the docket for fluoride fills about [uses both
hands to demonstrate a large space] and all the paper are there
and Dr. O'Hanian, who is my supervisor, and was not able to be here
today, he was there through that process, so he's the institutional
memory. I can get and have gotten out of the docket, for example,
the Public Health Service reports. So things that you need that
can come from the docket I can get them for you.
COMMITTEE MEMBER:
I'm sort of interested in having your thinking on adverse effects
because it sounds like the 1986 limit setting that you decided that
mild fluorosis was not an adverse effect. But is that now wide open
and is that for our consideration?
DR. DONAHUE:
I cannot answer that one very [WORD UNCLEAR]. I can say that that
was a decision not made in a vacuum, that's why they went to the
Public Service and they went to a variety of people. You [pointing
to Dr. Wagner] would probably know more than I do.
DR. WAGNER (A COMMITTEE MEMBER):
[UNCLEAR] -In the last review - [UNCLEAR] in the last review the
committee responsible they regarded it as a minimal effect, it's
cosmetic, not adverse.
COMMITTEE MEMBER:
[UNCLEAR]
COMMITTEE MEMBER:
Is severe fluorosis considered adverse?
DR. WAGNER:
Yes, absolutely. [FURTHER RESPONSE UNCLEAR]
COMMITTEE MEMBER:
Will you just review the charge for me again here - we're looking
at adverse effects of anything added to water other than
DR. DONAHUE:
No, no, no. EPA deals with what is already in the water from other
sources. And we tell people that when they exceed the MCL they must
treat the water to remove it. It does not involve addition to water.
COMMITTEE MEMBER:
OK. But you are specifically looking at disinfection and disease
control.
DR. DONAHUE:
No. That's caveat in the Safe Drinking Water Act. It says the Act
for EPA does not deal with the addition of any substance to water
except for -and it covers it by disinfection for disease control.
COMMITTEE MEMBER:
And then how do you define disease control insofar as it can be
viewed as having an [UNCLEAR]
DR. DONAHUE:
I can't identify that. The Act was done by Congress. That's one
sentence in the Act. I didn't give it to you exactly. And I cannot
tell you what they had in mind with they wrote that one sentence.
But it is one sentence. And I'll be happy to provide you with the
one sentence.
COMMITTEE MEMBER:
About the source of [UNCLEAR] . I want to make sure that I understand
this. The way the regulations were written it assumes a hundred
percent of fluoride intake comes from water, but..
DR. DONAHUE:
Of that 20 milligrams that was tied to it ...
COMMITTEE MEMBER:
But do you have mechanisms that so if you can decide that, say,
fifty percent comes from water, or you have half that number, is
that what you're saying?
DR. DONAHUE:
In other regulations, in many other regulations, we have what you
call a relative source contribution factor. When the data are from
a study that only looked at the amounts in water, you don't find
that. So in, otherwise, take the the case for barium, the basis
for our barium regulation is just based on barium in the drinking
water. And it doesn't deal with how much is in the diets for the
individuals that were involved. And so we have no relative source
on that one either. So fluoride is not alone.
PORTION OF Q&A IS OMITTED HERE.
COMMITTEE MEMBER:
Are the EPA standards for finished water product.
DR. DONAHUE:
Right
COMMITTEE MEMBER:
The current standards are based on the assumption that one hundred
percent of the fluoride comes from water?
DR. DONAHUE:
Well, that 20 milligrams per liter was estimated from drinking water
-a retrospective trying to get how much it was- that the people
who got the crippling skeletal fluorosis were exposed to, and as
far as I can tell it was from what was in the water although the
records ascribed a small amount of it to food, when it gets into
IRA there's a small portion that's ascribed to food.
COMMITTEE MEMBER:
Is this true for the SMCL as well?
DR. DONAHUE:
The SMCL was just based on the drinking water from what I can tell.
QUESTION FROM ATTENDEE JEFF GREEN:
I notice that the charge is directly related to the MCL and SMCL
and it seems to have leaped over the Maximum Contaminant Level Goal,
which has typically been the process by which you derive those.
DR. DONAHUE:
In this case they're identical. They don't have to stay identical.
But in this case they are identical.
QUESTION FROM ATTENDEE JEFF GREEN:
In other situations that we've seen, for example California public
health rules established its own number and the regulatory point
is another number. Is part of the charge to come to a MCLG as well
and then to derive those other two
DR. DONAHUE:
The MCLG is the health goal. Let's just start there. Then you have
to say is that technologically achievable and in today's climate
you have to say does the cost balance the benefit. Back in the '80s
when the first review of the regulations were established the benefit
costs requirement was not as stringent as what was established by
the 1996 Act. But in this case I call them both the same thing because
they are same. But they don't have to stay the same.
QUESTION FROM ATTENDEE JEFF GREEN:
But the Committee's task would be an MCLG?
DR. DONAHUE:
Well, yes.
DR. DOULL (CHAIR OF COMMITTEE):
Let me just, the statement of charge. Based on the reviews of the
toxiclogy, epidemiology and clinical effects the subcommittee will
evaluate independently the scientific and the technical basis of
the US EPA maximum contaminant level of 4 milligrams per liter and
secondary maximum contaminant level of 2 milligrams per liter and
will advise the EPA of the adequacy of the fluoride MCL and the
secondary MCL. That is our charge.
PORTION OF Q&A IS OMITTED HERE.
QUESTION FROM ATTENDEE PAUL CONNETT:
Two quick comments. One is on the MCLG versus the MCL discussion.
I think it's well established that the MCLG would be presumably
based on the best science, the science of toxicology. When you get
into the MCL you're talking about technical feasibility. I don't
know if this panel has been selected in terms of their expertise
in dealing with those kinds of issues which pertain to a regulatory
standard.
DR. DONAHUE:
We haven't asked them about cost benefit as part of their charge,
but it's a part of the charge does say the technical aspects of
fluoride - and what's enveloped in that is beyond what I know.
QUESTION FROM ATTTENDEE PAUL CONNETT:
The second comment I have. You mentioned the Institute of Medicine
and you said something about them coming around to the leanings
of a nutrient. I spent eight hours in a public session on that and
we had correspondence with both the President of the National Academy
of Sciences and the Institute of Medicine and they made it very
clear in a letter to us, in writing, that if anybody at that meeting
referred to fluoride as a nutrient they mispoke. They talk about
it as a beneficial element, not as a nutrient. And as far as I am
aware nobody has produced any scientific evidence that fluoride
is a nutrient.
DR. DONAHUE:
I made my judgment by reading the 1997 book. I was not there. I
didn't have any correspondence with them. And my judgment is from
reading that chapter in there both on calcium fluoride and Vitamin
E which are the first new dietary references. And I may have misread
it, but that's the way I read it.
PORTION OF Q&A IS OMITTED HERE.
COMMITTEE MEMBER (Charles Poole):
[____UNCLEAR] It's confusing. Again, it sounds now as though the
MCLG is what EPA wants us to look at. Is that correct?
DR. DONAHUE:
That's always where we begin. And then we ask if that is technologically
feasible and whether or not today the question that the cost justifies
the benefits and that isn't written into your charge. The technical
part, the word technical is in your charge.
COMMITTEE MEMBER (Charles Poole):
So we can address the MCL as part of our statement of task, but
we can't get there unless we
DR. DONAHUE:
do the MCLG
THE REST OF Q&A IS OMITTED.
Note: In a November 20, 1998, letter to Dr. Albert Burgstahler
and others, the presidents of both the Institute of Medicine and
the National Academy of Sciences write:
... Nowhere in the report* is it stated that fluoride is an essential
nutrient. If any speaker or panel member at the September 23rd
[1997] workshop referred to fluoride as such, they misspoke. As
was stated in Recommended Dietary Allowances 10th Edition, which
we published in 1989: "These contradictory results do not
justify a classification of fluoride as an essential element,
according to accepted standards. Nonetheless, because of its valuable
effects on dental health, fluoride is a beneficial element for
humans." See
copy of letter.
* Dietary Reference Intakes for Calcium, Phosphorus, Magnesium,
Vitamin D and Fluoride. Institute of Medicine. 1997.
This video from which this transcript was made is available upon
request to Fluoride Action Network.
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