This transcript is from a video filmed by Fluoride Action Network
August 12, 2003
Presentation by Joyce Donahue, PhD
Toxicologist, Office of Science and Techology,
US Environmental Protection Agency, Office of Drinking Water
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)
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.
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.
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.
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 = 20 mg/day (2 L/day) = 10 mg/L (2.5) = 4 mg/L
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.
Was the 2.5 the safety factor?
The derivation of that – where did that come from? Do you know?
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?
• 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.
• 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.
• 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.
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.
• Consumer Confidence Report• Sent by Utility once a year• Reports concentrations of fluoride monitored in water during the yearPublic 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.
• 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.
• 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.
• Published: Health Effects of Ingested Fluoride
• Reviewed health effects and occurrence data
• Concluded EPA’s MCL appropriate as interim standardMade research recommendations on
• Fluoride intake
• Dental fluorosis
• Bone strength and fractures
• CarcinogenictyRecommended 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.
• 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?
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.
Recent Data for NAS Consideration
First Nutritional Guidelines established by the Institute of Medicine (IOM) in 1997
• 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.
• 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.
• 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
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.
• 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].
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.
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.
NRC COMMITTEE MEMBER:
So could you clarify that for us.
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.
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:
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.
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
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.
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?
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.
Is severe fluorosis considered adverse?
Yes, absolutely. [FURTHER RESPONSE UNCLEAR]
Will you just review the charge for me again here – we’re looking at adverse effects of anything added to water other than
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.
OK. But you are specifically looking at disinfection and disease control.
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.
And then how do you define disease control insofar as it can be viewed as having an [UNCLEAR]
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.
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..
Of that 20 milligrams that was tied to it …
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?
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.
Are the EPA standards for finished water product.
The current standards are based on the assumption that one hundred percent of the fluoride comes from water?
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.
Is this true for the SMCL as well?
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.
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
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. 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.
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.
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?
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
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  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.
Note: This was taken from FAN’s original website, http://www.fluoridealert.org/wp-content/pesticides/nrc.aug.2003.epa..html