MERCURY IN DENTAL AMALGAMS: AN

EXAMINATION OF THE SCIENCE

HEARING

BEFORE THE

COMMITTEE ON

GOVERNMENT REFORM

HOUSE OF REPRESENTATIVES

ONE HUNDRED SEVENTH CONGRESS

SECOND SESSION

NOVEMBER 14, 2002

Serial No. 107–159

Printed for the use of the Committee on Government Reform

(

Available via the World Wide Web: http://www.gpo.gov/congress/house

http://www.house.gov/reform

MERCURY IN DENTAL AMALGAMS: AN EXAMINATION OF THE SCIENCE

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MERCURY IN DENTAL AMALGAMS: AN

EXAMINATION OF THE SCIENCE

HEARING

BEFORE THE

COMMITTEE ON

GOVERNMENT REFORM

HOUSE OF REPRESENTATIVES

ONE HUNDRED SEVENTH CONGRESS

SECOND SESSION

NOVEMBER 14, 2002

Serial No. 107–159

Printed for the use of the Committee on Government Reform

(

Available via the World Wide Web: http://www.gpo.gov/congress/house

http://www.house.gov/reform

(II)

COMMITTEE ON GOVERNMENT REFORM

DAN BURTON, Indiana, Chairman

BENJAMIN A. GILMAN, New York

CONSTANCE A. MORELLA, Maryland

CHRISTOPHER SHAYS, Connecticut

ILEANA ROS-LEHTINEN, Florida

JOHN M. MCHUGH, New York

STEPHEN HORN, California

JOHN L. MICA, Florida

THOMAS M. DAVIS, Virginia

MARK E. SOUDER, Indiana

STEVEN C. LATOURETTE, Ohio

BOB BARR, Georgia

DAN MILLER, Florida

DOUG OSE, California

RON LEWIS, Kentucky

JO ANN DAVIS, Virginia

TODD RUSSELL PLATTS, Pennsylvania

DAVE WELDON, Florida

CHRIS CANNON, Utah

ADAM H. PUTNAM, Florida

C.L. ‘‘BUTCH’’ OTTER, Idaho

EDWARD L. SCHROCK, Virginia

JOHN J. DUNCAN, JR., Tennessee

JOHN SULLIVAN, Oklahoma

HENRY A. WAXMAN, California

TOM LANTOS, California

MAJOR R. OWENS, New York

EDOLPHUS TOWNS, New York

PAUL E. KANJORSKI, Pennsylvania

PATSY T. MINK, Hawaii

CAROLYN B. MALONEY, New York

ELEANOR HOLMES NORTON, Washington,

DC

ELIJAH E. CUMMINGS, Maryland

DENNIS J. KUCINICH, Ohio

ROD R. BLAGOJEVICH, Illinois

DANNY K. DAVIS, Illinois

JOHN F. TIERNEY, Massachusetts

JIM TURNER, Texas

THOMAS H. ALLEN, Maine

JANICE D. SCHAKOWSKY, Illinois

WM. LACY CLAY, Missouri

DIANE E. WATSON, California

STEPHEN F. LYNCH, Massachusetts

———

BERNARD SANDERS, Vermont

(Independent)

KEVIN BINGER, Staff Director

DANIEL R. MOLL, Deputy Staff Director

JAMES C. WILSON, Chief Counsel

ROBERT A. BRIGGS, Chief Clerk

PHIL SCHILIRO, Minority Staff Director

(III)

C O N T E N T S

Page

Hearing held on November 14, 2002 ...................................................................... 1

Statement of:

Haley, Boyd E., professor and chair, Department of Chemistry, University

of Kentucky, Lexington, KY; G. Mark Richardson, director and risk

assessment specialist, Risklogic Scientific Services, Inc., Ottawa, Canada; Richard D. Fischer, past president of International Academy of

Oral Medicine and Toxicology; J. Rodway Mackert, professor of oral

rehabilitation, Medical College of Georgia Dental School, Athens, GA,

on behalf of the American Dental Association; Gregory Stoute, president, National Dental Association, Cambridge, MA; and Michael Bender, director, Mercury Policy Project, Montpelier, VT ................................. 25

Tabak, Lawrence A., Director, National Institute of Dental and

Craniofacial Research, National Institutes of Health, Bethesda, MD;

and Dr. David W. Feigal, Director, Center for Devices and Radiological

Health, Food and Drug Administration, Rockville, MD ............................ 108

Letters, statements, etc., submitted for the record by:

Bender, Michael, director, Mercury Policy Project, Montpelier, VT, prepared statement of ........................................................................................ 88

Burton, Hon. Dan, a Representative in Congress from the State of Indiana, prepared statement of .......................................................................... 5

Feigal, Dr. David W., Director, Center for Devices and Radiological

Health, Food and Drug Administration, Rockville, MD, prepared statement of ........................................................................................................... 118

Fischer, Richard D., past president of International Academy of Oral

Medicine and Toxicology, prepared statement of ....................................... 47

Haley, Boyd E., professor and chair, Department of Chemistry, University

of Kentucky, Lexington, KY, prepared statement of .................................. 29

Mackert, J. Rodway, professor of oral rehabilitation, Medical College

of Georgia Dental School, Athens, GA, on behalf of the American Dental Association, prepared statement of ........................................................ 56

Richardson, G. Mark, director and risk assessment specialist, Risklogic

Scientific Services, Inc., Ottawa, Canada, prepared statement of ............ 37

Stoute, Gregory, president, National Dental Association, Cambridge, MA,

prepared statement of ................................................................................... 83

Tabak, Lawrence A., Director, National Institute of Dental and

Craniofacial Research, National Institutes of Health, Bethesda, MD,

prepared statement of ................................................................................... 110

Watson, Hon. Diane E., a Representative in Congress from the State

of California, prepared statement of ........................................................... 12

(1)

MERCURY IN DENTAL AMALGAMS: AN

EXAMINATION OF THE SCIENCE

THURSDAY, NOVEMBER 14, 2002

HOUSE OF REPRESENTATIVES, COMMITTEE ON GOVERNMENT REFORM, Washington, DC.

The committee met, pursuant to notice, at 11:13 a.m., in room

2154, Rayburn House Office Building, Hon. Dan Burton (chairman

of the committee) presiding.

Present: Representatives Burton, Gilman, Otter, Norton, and

Watson.

Also present: Representatives Norwood, Simpson, and Linder.

Staff present: Kevin Binger, staff director; David A. Kass, deputy

chief counsel; S. Elizabeth Clay and John Rowe, professional staff

members; Blain Rethmeier, communications director; Allyson

Blandford, assistant to chief counsel; Robert A. Briggs, chief clerk;

Robin Butler, office manager; Joshua E. Gillespie, deputy chief

clerk; Nicholis Mutton, deputy communications director; Susie

Schulte, legislative assistant; Mindi Walker, staff assistant;

Corinne Zaccagnini, systems administrator; Sarah Depres, minority

counsel; Ellen Rayner, minority chief clerk; and Jean Gosa and

Earley Green, minority assistant clerks.

Mr. BURTON. Good morning. A quorum of the committee being

present, the Committee on Government Reform will come to order.

I ask unanimous consent that all Members’ and witnesses’ written and opening statements be included in the record. And without

objection, so ordered.

I ask unanimous consent that all articles, exhibits, and extraneous or tabular material referred to be included in the record. And

without objection, so ordered.

I ask unanimous consent that Congressman Norwood, Linder,

and Simpson, who are not members of the committee, be permitted

to participate in today’s hearing. Without objection, so ordered.

Sorry I am a little bit late. I appreciate all of you being here.

Over the last 3 years, the Government Reform Committee has

looked at health and safety issues related to mercury-containing

products.

In July 2000, we held a hearing entitled, ‘‘Mercury in Medicine—

Are we Taking Unnecessary Risks?’’ We focused on why mercury

is put into vaccines that are given to children. We received a report

during that hearing that indicated that the symptoms of mercury

toxicity are similar to the symptoms of autism.

That was followed up by a hearing on April 18, 2002, entitled,

‘‘The Autism Epidemic—Is the NIH and CDC Response Adequate?’’

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We found out during our investigations over the past several

years that to our knowledge there has never been a real test of

whether or not thimerosal and mercury in vaccines is a problem.

In the 1920’s, when they first started using thimerosal, which contains mercury and is used as a preservative, it was tested on I

think twenty-some people who had meningitis, all of whom died,

and because they didn’t die or have any reactions to the thimerosal

before they died, they said that it really did not have any adverse

effect and it was a good preservative.

To my knowledge, there has never been any blind study, double

blind study, or anything else done on thimerosal or mercury in vaccines since the 1920’s. If that is the case, and we believe it is, that

is a real failure of our health agencies because that should have

been checked out.

We have conducted numerous hearings on the Vaccine Injury

Compensation Program. I am pleased that Dr. Dave Weldon and

our ranking minority member, Congressman Waxman, joined me in

co-sponsoring legislation to improve the compensation program. I

believe through our oversight activities that we have made it absolutely clear to the Department of Justice and the Department of

Health and Human Services that the intent of Congress was and

remains that the National Vaccine Injury Compensation Program

should be a no-fault compensation program, not a contentious tort

system. I really regret that we have not been able to get this bill

passed because it would really help a lot of people, and there are

an awful lot of people who have suffered who have not been compensated because of vaccine related injuries.

Today’s hearing will focus primarily on the science regarding

mercury-containing dental amalgams.

Early in our investigation, I was accused of being ‘‘anti-vaccine.’’

Now that we are examining the science behind the use of mercury

in dental amalgams, I suppose I will be characterized as anti-dentistry. And after all the money I have spent on my teeth, that cannot be the case. [Laughter.]

Neither charge could be further from the truth.

Immunizations have been portrayed as one of the greatest advances in public health during the past century, second only to

clean water and improved hygiene. I think that is true, although

we need to make sure that vaccines are as safe as possible. I am

for vaccines, I am for good dentistry, but we want to make sure we

are not putting toxic chemicals into our bodies and into our children. Dentistry is a noble profession that has contributed to Americans’ overall health and quality of life. While immunizations may

offer a great benefit, they also carry risks. And while dentistry offers great benefit, the continued use of a toxic substance such as

mercury needs to be examined.

Mercury is mercury, whether it is methyl or ethyl, organic or inorganic. There is no one in this room or in all of science who can

say with any level of credibility that any form of mercury is safe.

While many people have absolutely no problem with being injected

with thimerosal-containing vaccines, and while mercury-containing

dental amalgams have been used for over 150 years, we have a responsibility to protect those who are pregnant women, infants and

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young children, those who have autoimmune dysfunction, and the

elderly.

And with dental amalgams, I am also talking about economically

disadvantaged people of all ages who depend upon Medicaid for

dental care. They either get fillings with mercury, or they get no

fillings at all.

Are we giving them short-term relief by helping pay for their

dental work, only to set them up for disaster, for long term problems down the road? We do not know.

The simple fact is that mercury is one of the most toxic minerals

on earth, second only to radioactive materials.

The fillings that typically are called ‘‘silver’’ fillings because of

their color probably should be called mercury fillings. They consist

of 50 percent or more of mercury. And a lot of people do not even

know that. When the mercury is mixed with an alloy of powdered

metals, it becomes Dental Amalgam.

For many years dental schools taught that when the amalgam

hardens it becomes inert. They taught that there was no further

risk from the mercury. However, from research, we now know that

mercury vapor continues to leech from amalgams for as long as it

remains in the mouth. The fumes are inhaled into the human body

and minute particles chip off and are ingested into the stomach as

fillings wear out.

This has important health implications, since mercury has a long

half-life and has the potential for doing significant damage to the

kidneys and brain. For reasons that are not well understood, some

individuals seem to hold on to the mercury absorbed by their body,

leaving them at risk for neurological or renal damage.

In 1999 the U.S. Agency for Toxic Substances and Disease Registry published the ‘‘Toxicological Profile in Mercury.’’ That was in

1999 that it was published. This report stated that poisonous mercury vapors are constantly emitted from amalgam, that these vapors go first to the brain, and that children are most at risk because their brains are still developing. The report further states

that the mercury crosses the placenta into the developing fetus,

and that it is transmitted through a mother’s milk to the infant.

The Food and Drug Administration has taken what appears to

be a bipolar approach to protecting the public from mercury. While

denying that thimerosal in vaccines or mercury in dental amalgams poses any health risk, it has taken a stand against mercury

in other products.

The FDA has repeatedly issued strong warnings cautioning the

public, and in particular pregnant women and young children, to

restrict their consumption of tuna and other fish that is known to

contain mercury.

The FDA has determined that mercury compounds used as active

ingredients in over-the-counter drug products were not ‘‘generally

recognized as safe.’’ Mercurochrome had mercury in it. When we

were kids we used to put it on our skin to heal wounds. It is a topical dressing. You cannot sell it anymore, you cannot use it anymore

because it has mercury in it and they said it might leech through

the skin and into the body and into the brain. And yet we inoculate

our kids with thimerosal in it, and have for years, and we put

metal amalgams into their mouths.

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They also have not approved any mercury-containing compounds

as food additives.

The FDA also states that lead, cadmium, and mercury are examples of elements that are toxic when present at relatively low levels.

I have asked before, and I will ask again, how is it that mercury

is not safe for food additives and over-the-counter drugs but it is

safe in our vaccines and in our dental fillings?

There are alternatives to mercury-containing amalgams.

Shouldn’t we exercise an abundance of caution and hasten the use

of these alternatives?

Before I conclude, I want to commend Congresswoman Diane

Watson of California for her initiative in sponsoring H.R. 4163, the

Mercury in Dental Filling Disclosure and Prohibition Act.

As I have already stated, the Federal Government must exercise

special care for vulnerable population groups. Physical and in particular neurological damage from mercury is an issue that crosses

all boundaries—geographic, economic, ethnic, religious, age, and

gender—all boundaries.

It is said that you cannot stop an idea whose time has come.

Hasn’t the time come for us to really examine this and whether or

not exposing people to mercury through medical interventions is

something that we should do away with.

I look forward to hearing from our witnesses today, to learning

about the scientific research that has been conducted and to learn

about what research still needs to be done.

The Record will remain open until November 28, 2002.

[The prepared statement of Hon. Dan Burton follows:]

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Mr. BURTON. I now recognize Ms. Watson for her statement, and

after that we will go to our guests.

Ms. WATSON. Thank you so much, Mr. Chairman. I would like

to thank you for your leadership and your hard work on this important issue. Above and beyond your diligence as chairman of the

Government Reform Committee, I applaud your vision and compassion on public health issues. Your ability to reach across the aisle

and co-author H.R. 4163 is a tribute and is a testimony to your

dedication to, and your concern for the public well being. I truly believe that elected public officials are the stewards of public health.

I also want you to know that the importance of this issue is highlighted by your decision to have this hearing before stepping down

as Chair. So thank you and your staff again. I look forward to this

and other work we will do together in the future.

As a former Chair of the California Health and Human Services

Committee for 17 years, I was given constant testimony as to the

status of Californian’s health, especially those in the lower socioeconomic sector of our population. In the medical professions, including dentistry, professionals have sworn to ‘‘do no harm.’’ Dentists have stood behind a long history of utilizing mercury; however, a long history of use is no excuse.

Mercury in any form is as much of a health risk as lead in paint

and asbestos. Mercury is being taken out of other health care products as well as disinfectants, thermometers, childhood vaccines,

and even horse medicine. With mercury, a highly toxic substance,

as the main ingredient in dental amalgams, I can only ask a very

simple question—why take the risk?

In 1991 I wrote a law, Section 1648.10 of the California State

Business and Professions code, that mandated a fact sheet be produced by the California State Dental Board stating the risks as

well as the efficacies of dental materials. Over the next 9 years, the

board did not comply. But I am pleased to see that our Governor

has installed a new California Dental Board. For the first time in

California history, the legislature closed down a State board before

its authorization time had run its course.

Of biggest concern to me when I wrote the law was amalgam, because it is composed of approximately 50 percent mercury, a very

pervasive and persistent toxic element. Mercury has been placed on

the list of reproductive toxic substances in California’s Proposition

65. I found that most consumers did not know amalgam contained

mercury, and it is easy to see why. The filling is simply called ‘‘silver’’ by organized dentistry—a very deceptive misnomer.

Mercury must be removed from the last known use in the human

body. Again I ask, why take the risk? Consumers have not been informed about the differing properties of various dental materials—

for example, resin, gold, porcelain, and mercury amalgam—and

they have certainly not been told of the possible risks to their

health and the environment. The public has a right to know. The

public has a right to be informed and to make choices.

Regrettably, the American Dental Association has a provision in

its code of ethics to stop dentists from initiating communications

with patients about the risks of mercury dental fillings. I would say

shame on them. This what I call ‘‘the gag rule’’ has unfortunately

been enforced by many dentist-dominated State dental boards. I

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am happy to report that yesterday the Iowa Dental Board repealed

its gag rule, and that earlier this year Oregon did likewise. The

dental board in my home State of California repealed its gag rule

in 1999. It is now time for the American Dental Association to stop

blocking communications from dentists informing their patients

about amalgam. It is time for every State dental board to stop enforcing this gag rule and to do the right thing.

This current legislation, H.R. 4163, introduced by Chairman Burton and I, is an extension of my California State disclosure law.

The bill has three main goals: One, to ban mercury amalgam for

children under 18, pregnant women, or nursing mothers, effective

immediately; two, dental disclosure and a health warning for all

consumers, effective immediately; and three, a phase-out of all

mercury amalgam use in the United States by January 1, 2007.

The provisions of the bill reflect the fact that mercury poses a

particular risk to children, lactating and pregnant women. The

U.S. Agency for Toxic Substances and Disease Registry states that

poisonous mercury vapors are constantly emitted from dental amalgams, that these vapors go first to the brain, and that children are

most at risk because their brains are still developing. The report

further states that mercury can go through the placenta to the

fetus, and through the mother’s breast milk to the infant. The two

most common occurrences of mercury toxicity in humans are from

dental amalgams and fish. It is time pregnant women learn as

much about the amalgam risks as they do the risks from mercurylaced fish. The fact that mercury vapor is continually being emitted

from the mercury amalgam fillings is not disputed by anyone.

Again I ask, why take the risk?

There is a growing international movement in both scientific and

dental communities that now disapprove of amalgam, and the government of Canada advised in 1996 against its use for pregnant

women, for children, and people with kidney problems, orthodontic

braces, or mercury allergies. Indeed, the major manufacturer of

amalgam warned back in 1997 that amalgam is contra indicated,

meaning not to be used, for those five vulnerable population categories. Sweden, Germany, Austria, and now Norway have announced plans to go mercury-free, and the U.K. says pregnant

women should not get mercury fillings.

What is happening in the United States? We hope that we will

see a movement starting with this bill, because mercury is an environmental poison and listed as the No. 1 environmental poison by

the World Health Organizations.

I am very pleased to inform you that the National Convention of

the NAACP endorsed H.R. 4163. And I tell you how significant that

is, because I had a group of minority dentists come to me and they

said, ‘‘How dare you scare people into thinking that they do not

want to come in because we are putting poisons in their mouths.’’

I said, ‘‘You as medical people, are you saying to me that you do

not want to inform your patients about what is in that amalgam,

if there is a risk? I do not understand, if you are sworn to do no

harm.’’

So to be able to convince the NAACP, and all these dentists who

are members, that there is a considerable threat to lower socioeconomic people and people that they serve, because they are the

11

ones that go in and get the fillings and they are the ones who are

at risk and they should be able to know, and we should be able to

inform them, then they can make the choice. The dentists said to

me, ‘‘Well, it is cheaper. You know, people do not like to go to the

dentist anyway.’’ That does not prevail. That is not a compelling argument when a person’s health is at risk. So we have the NAACP’s

endorsement, and I am very, very pleased to announce that.

And last, the subject of the Food and Drug Administration classification of dental mercury amalgam must be addressed. The FDA

must come forward and be open and honest with Americans.

And so we are hoping that this bill, Mr. Chairman, will be a beginning. I look forward to the testimony that is going to be presented here this morning. I am pleased to have the opportunity to

hear the scientific and regulatory testimony on this issue. I think

there is a lot to be learned, a lot to go public, and a lot for Americans to consider.

So thank you for your leadership, and thank you to the presenters. If I slip out for a moment, I have business in another building

but I will have heard your testimony. So thank you, Mr. Chairman,

for the opportunity.

[The prepared statement of Hon. Diane E. Watson follows:]

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Mr. BURTON. We will go next to Mr. Otter, who is a member of

the committee, and then we will go to our guests, Mr. Linder and

Mr. Norwood.

Mr. OTTER. Thank you, Mr. Chairman. It had been my intent

when you offered me the microphone to defer to my colleagues, all

three of which are guests here in our committee room today. But

knowing that they are dentists, it does not bother me to have the

dentists wait on me for once. [Laughter.]

So I am going to go ahead. Dentists have used amalgam fillings

safely for over a century. As my dentist colleagues can and will attest to, I believe, dentists have come to rely on the use of amalgam

as a harmless, dependable, and cost-effective material with which

to treat their patients. In fact, numerous studies have already been

conducted, apparently not for the benefit of those who would wish

to ban amalgam. An assortment of health organizations, including

the World Health Organization, the U.S. Public Health Service, the

Food and Drug Administration has issued an opinion on this, the

Center for Disease Control and Prevention and National Health Institute, all conducted and concluded that ‘‘with the exception of

rare personal allergic reaction to amalgam components, there is no

evidence that the use of amalgam in dental fillings causes consistent health problems in our population.’’

Given these conclusions, H.R. 4163 simply fixes a problem that

does not exist, and therefore unnecessarily eliminates I believe a

very cost-effective treatment option for dentists and for their patients.

The very function of the Department of Health and Human Services is to protect our population from health risks. This Congress

and many Congresses before it continue to fund these organizations. Why then does Congress ignore the research studies and continue to second-guess and undermine the conclusions of these very

organizations that we fund?

This country enjoys the most accurate and comprehensive stateof-the-art medical research institutions in the world. We should

heed the advice and conclusions of these health professionals. The

use of amalgams should remain a viable option for dentists and for

their patients. Simply put, Mr. Chairman, I hope we are not pulling the wrong tooth here today. Thank you.

Mr. BURTON. Thank you, Mr. Otter.

Mr. Linder.

Mr. LINDER. Nothing, Mr. Chairman.

Mr. BURTON. No opening statement? Mr. Norwood.

Mr. NORWOOD. Thank you, Chairman. I would like to particularly thank you for extending the courtesy of us participating in today’s hearing. I for one am very grateful for this opportunity.

I practiced dentistry for 25 years and I have placed thousands

and thousands of dental amalgam restorations in my patients. And

you know what? If I have been hurting my patients, I want to

know about it. But I want to know about it with good science. I

want to know about it from people who are trying to look at this

issue for all the right reasons.

I have always known this material to be safe and effective and

safe for me. If you think my patients have been around amalgam

very much, I have been around it many, many greater hours and

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times than any patients that I have. Now I will grant you, there

are some Members of Congress who might say that it has affected

me greatly. [Laughter.]

But my wife seems to think it is OK. And I want you to know

that I today believe it to be OK.

I am very worried about hearings like this and what it can do

to the dental health of the people of this Nation. Misinformation

is very, very dangerous. Those of us who have been trying to serve

our patients and improve the dental health of this Nation and have

been on the front line of this, the greatest majority agree that this

is a very safe restoration. The reason we call it silver is very simple—it is silver. It is not mercury. Mercury is toxic; I agree that

it is toxic, particularly in some doses. So is chlorine, but salt is not

deadly unless you inhale too much of it, I suppose. Mercury is not

the same thing as an amalgam. We need to make that very clear

in this hearing today.

We must put our emphasis on good peer reviewed science so as

to not harm our citizens and keep them away from seeking dental

care. I have spent my life trying to get patients to come and be

treated so that in this Nation we can have the best dental care in

the world. And this is not the way to go about improving dental

care in America. If we are going to take action on the use of dental

amalgam, we better be darn right or we are going to affect a large

part of our population’s ability to access care. And that should be

very much part of our concern here too.

Mr. Chairman, I look forward to this hearing more than I can

ever tell you. I am grateful for you allowing us to be here. I yield

back my time.

Mr. BURTON. Thank you, Dr. Norwood.

Mr. Simpson, my buddy from Idaho.

Mr. SIMPSON. Thank you, Mr. Chairman. I, too, want to extend

my appreciation for allowing us to sit with your committee today

to explore this issue. And I also want to thank you for actually

holding this hearing on H.R. 4163. I appreciate your sincere concern about this subject, and Congresswoman Watson’s concern

about this subject. Even though I am opposed to the bill, it is important to hold these hearings I think to be able to put forth the

science concerning amalgam and other mercury-containing medical

treatment.

Sometimes in this job, in fact most often in this job, we react to

public concerns. Sometimes we over-react to public concerns. And

let me say without equivocation that if there were any credible and

supportable evidence that amalgam was unsafe to the patient, I am

certain that the ADA, joined by Dr. Norwood, Dr. Leonard, and myself, would immediately call for its removal from the approved

products list. I would also have the amalgam fillings removed from

my mouth, of which I have a few.

What concerns me is some of the implication that was stated

during the testimony of Congresswoman Watson that somehow this

is a money issue with dentists, that they are less concerned with

their patients’ health. I can assure you that is not the case. I am

not sure what she meant by stop enforcing these board-enforced

gag orders that prevent dentists from communicating to their patients the effects of amalgam. I was always free in the 22 years I

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practiced dentistry to communicate whatever I wanted to to my patients. In fact, not only was I free to do so, I had an obligation to

communicate with them the effects of the treatment that I was

going to render them. So I do not know what gag order she is specifically talking about.

It is important to remember that mercury and amalgam, as Dr.

Norwood said, are not the same thing. Amalgam remains an important restorative material in dentistry, and I think will so in the future. Yes, we are developing other types of restorative material.

Those are not appropriate in all circumstances and oftentimes

amalgam is the best restorative material that you can use in certain circumstances.

So I believe, as everyone has said, that our decisions, and I am

sure you would agree, should be based on science and not over-reacting to public concern, while we should take public concern into

consideration. I do appreciate your holding these hearings today so

that we can put the science forward concerning amalgam. Thank

you.

Mr. BURTON. Thank you.

We will now go to our witnesses. I would submit to my colleagues

who are dentists, the March 1999 study, I do not know if you have

seen that or not, does have some interesting things that might be

illuminating for you.

I would now like to call to the dais Dr. Boyd Haley, Ph.D., Professor and Chair of the Department of Chemistry, University of

Kentucky, Lexington, Kentucky; Dr. G. Mark Richardson, Director

and Risk Assessment Specialist, Risklogic Scientific Services, Inc.,

Ottawa, Ontario, Canada; Dr. Richard D. Fischer, a good friend of

mine from Annandale, Virginia, past President of the International

Academy of Oral Medicine and Toxicology; Dr. J. Rodway Mackert,

Professor of Oral Rehabilitation, Medical College of Georgia Dental

School, Athens, Georgia, who is here on behalf of the American

Dental Association, your colleagues; Dr. Gregory Stoute, Cambridge, Massachusetts, President of the National Dental Association; Mr. Michael Bender, Director of the Mercury Policy Project,

Montpelier, Vermont.

Would you all please stand and raise your right hands.

[Witnesses sworn.]

Mr. BURTON. Be seated. We will start with you, Dr. Haley. I

would like to, since we have such a large number of witnesses, I

would like to have you confine your remarks to as close to 5 minutes as possible so we can get to questions, because I think there

is going to be an abundance of questions for all of you.

Dr. Haley.

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STATEMENTS OF BOYD E. HALEY, PROFESSOR AND CHAIR, DEPARTMENT OF CHEMISTRY, UNIVERSITY OF KENTUCKY,

LEXINGTON, KY; G. MARK RICHARDSON, DIRECTOR AND

RISK ASSESSMENT SPECIALIST, RISKLOGIC SCIENTIFIC

SERVICES, INC., OTTAWA, CANADA; RICHARD D. FISCHER,

PAST PRESIDENT OF INTERNATIONAL ACADEMY OF ORAL

MEDICINE AND TOXICOLOGY; J. RODWAY MACKERT, PROFESSOR OF ORAL REHABILITATION, MEDICAL COLLEGE OF

GEORGIA DENTAL SCHOOL, ATHENS, GA, ON BEHALF OF

THE AMERICAN DENTAL ASSOCIATION; GREGORY STOUTE,

PRESIDENT, NATIONAL DENTAL ASSOCIATION, CAMBRIDGE,

MA; AND MICHAEL BENDER, DIRECTOR, MERCURY POLICY

PROJECT, MONTPELIER, VT

Mr. HALEY. If I could have the first slide. We will go to the

science. This is what people are wanting to see. This is research

done where we looked at the mercury level in a birth hair of babies, those that have become autistic and those that are controls

are normal. And if you look at this slide and you look at the level,

if you look at the top line that is controls, and below that, on the

abscissa of that is the number of dental amalgams that the birth

mother had. And in control children, you see an elevation in the

birth hair with increasing number of amalgam fillings. However,

with the autistics, the bottom line, no matter how many amalgam

fillings the mother has, they have less on average of about 0.5

parts per million in their hair.

A reasonable interpretation of this is that autistic children represent a subset of the population that cannot effectively excrete

mercury. One thing you cannot disagree with is that autistics handle mercury different than children who are born and who do not

become autistic.

This slide shows the severity of the disease. As you go across, as

the level of mercury in parts per million in the hair of these children decreases, the severity of the autism increases. And what you

will notice is the female to male ratios are quite different in the

different categories. On the far left, where the mercury levels are

on average higher, you will see that the females almost all fall

below the average amount of mercury in their hair, whereas the

males are in the top and the females are roughly 50 percent. If you

go to the next one, you see the female population disappears, drops

dramatically. And as you go to the higher level, it is even more pronounced. There is only one female in the severe autism case. This

fits into the situation where boys get the disease about four to five

times more often than girls and they are the ones that get the severe cases of autism by far the most.

Could I have the next slide. If we look at the synergistic

toxicities, and this is my major disagreement with the dental association, you cannot tell somebody what level of mercury is safe. A

person that is exposed to lead, or aluminum, or a number of other

things that is then exposed to mercury will have a totally different

reaction than that individual who is not exposed, the same individual, if he were not exposed to other toxic metals, etc.

The thing that is very interesting here—this is with neurons in

culture, the mammalian neurons, and the top line is the control—

if you look at the green, that is the one that is critical, if we take

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testosterone, which has no effect on the neurons when it is added

alone, if you add it to a level of 15 nanomolar thimerosal, which

takes several hours to kill the neurons, it will kill all the neurons

100 percent in the first time point. So, logically or reasonably

speaking, the presence of testosterone enhances the toxicity of

ethyl-mercury from thimerosal by over 100-fold. This fits into the

data by Dr. Barren Cohen in London where he measured the testosterone level of the amniotic fluid of females that give birth to

autistic children, compared it to controls, and the one consistent

feature was that their amniotic fluid contained high levels of testosterone, the highest levels.

So we have a gender risk factor here that is put in by a hormone.

I would also point out that estrogen has exactly the opposite effect.

It is protective. If we add estrogen to this study, fewer of the neurons die out at 12 hours. And this fits into the model where you

see that people say women on estrogen therapy are less likely to

become demented with Alzheimer’s disease.

Could I have the next slide. This is the one that amazes me that

our Government, the American Medical Association, the National

Institutes of Health seem to totally ignore. This is a disease called

idiopathic dilated cardiomyopathy. This is young athletes that drop

dead during high school athletic events. They have 22,000 times

more mercury in their heart tissue. Most of these kids are innercity kids or kids from the countryside, they are not people that eat

shark, tuna, or mackerel. Where does the mercury come from? And

is it causal, or is it just a happenstance? This needs to be addressed. If you want science, why don’t you have NIH go look at

this.

Could I have the next slide. This is the fact about neurons. If you

take neurons in culture, you see significant death at five

nanomolar, 5 times 10 to the minus 9th molar, that is roughly

100fold less than what you find in the brain of the average person.

They have concentrations around 10 to the minus 7 molar, although it varies dramatically. So we can say this compound mercury itself is extremely neurotoxic if it gets into the brain and if

you do not have the reducing equivalence to effectively chelate and

remove it by the natural process.

Could I have the next slide. This is the problem with neurons.

The major protein in neurons is a protein called tubulin, it is the

one at the bottom, and it forms into something called mycrotubuls,

which you see at the very bottom. It is the major protein in there

and when one atom of mercury binds to one molecule of tubulin,

it disrupts that entire structure. Our studies have shown that mercury mimics the effects that we see in Alzheimer’s disease. And so

we are going to be talking about this protein for just a few minutes.

Could I have the next slide. This is what we do with our research, and I cannot explain photofendelabeling except to say that

NIH funded it for about 27 years in my laboratory and this technique is used by NIH, Mayo Clinic, and everyone else that do

roughly the same thing that I do. When you look at an Alzheimer

diseased brain, you will find that on the average about 80 percent

of them have a dramatically lowered or totally abolished

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photolabeling or viability of this protein called tubulin. This is significantly found only in Alzheimer diseased brain.

Could I have the next slide. When you take heavy metals, all of

them, we tested all of them, most of them are toxic but if you

chelate them with the normal compounds that exist in your body,

citrate, glutamate, or add EDTA, a common food additive which is

used to chelate and render heavy metals less toxic, it stops the toxicity of every one of the heavy metals except mercury and it makes

the mercury more toxic. So we do not have the level of protective

compounds in our brain to render mercury less toxic or non-toxic.

It just does not work. We did not evolve with any protective mechanisms except for glutathione and metalthien, but definitely other

compounds do not work. And you will see that mercury exactly

mimics the profile that you see in an Alzheimer diseased brain and

that it does not affect the actin which is the bottom band below

that.

Could I have the next slide. This is the take home lesson. We

have two controls on the right with zero mercury, it is not all showing on your format here, and two Alzheimer diseased subjects on

the left. The bottom line is as you add low levels of mercury—and

you need to understand that this is done in a test tube and it is

done within a few minutes, it is not letting it sit there for days,

weeks, years at constant low level exposure. You can make a control brain look like an AD brain by the mere addition of mercury.

Could I have the next slide, please. This is an enzyme. We published this in Molecular Brain Research called creatine kinase in

Alzheimer’s diseased brain. It is over 97 percent inhibited. I have

done a lot of biochemistry on this, way before the mercury issue

ever came up, it has a very reactive sulfur in the active site. If you

take an amalgam filling, drop it into distilled water, let it sit there,

as we show here, 15 minutes, you see significant inhibition of the

ability of that enzyme to make creatine phosphate. So you cannot

tell me that breathing mercury vapor, having it going into your

brain, if you are a person that is going to become Alzheimer’s diseased is a good idea. It is a risk factor that we do not need to take.

Could I have the next slide, please. This is the last slide. If this

were any other metal, it would have been kicked out and named

as a cause of Alzheimer’s disease a long time ago. It causes all the

aberrant biochemistry, based on the simple process it inhibits

thyroreactive enzymes. If you take neurons in culture and you add

mercury to it, you generate neurofibrillary tangles, the diagnostic

hallmark of the disease. You see the level of glutathione drop dramatically, which is also found in these type of diseases. You see the

hyper-phosphorylation of protein called Tau which is only seen in

Alzheimer’s disease, and it increases the production and secretion

of beta-amyloid protein which makes the senile plaques, which is

the other major diagnostic hallmark of the disease. So if you have

all of the scientific evidence behind it, this is where most people in

medicine would look at it and say, hey, this is kind of conclusive

evidence. But it is done on animals, it is done on a thing. So unless

we take somebody and do it on a human, the dental association

does not want to believe that this is something that is relevant.

Most medicine fits into this category.

And I would like to point out one other——

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Mr. BURTON. Doctor, if you could summarize.

Mr. HALEY. Sure. OK. Mercury is classified by dentistry as a

Class I material, totally safe. If I order that and it comes into my

chemistry department, it is placed in the most toxic of categories.

So there is the difference; the cavalier attitude that it is safe, it is

not toxic, and the attitude that, no, this is one of the most toxic

chemicals known. I think they need a wake-up call. Thank you.

[The prepared statement of Mr. Haley follows:]

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Mr. BURTON. Thank you.

Dr. Richardson.

Mr. RICHARDSON. Thank you. Ladies and gentlemen of the committee, it is an honor and privilege to address you this morning.

Dental amalgam is the single largest source of mercury exposure

in the U.S. population. This is acknowledged by the U.S. Environmental Protection Agency, amongst other agencies in this country.

While an employee with the Canadian Federal department of

health, I was directed in 1994 to undertake an assessment of mercury exposure and risks from dental amalgam on behalf of that

country. Subsequently in 1996, I was commissioned by the government of Sweden to contribute an updated assessment of those risks

for their review of this issue.

As you might expect, the work received considerable criticism

from the dental establishment, in Canada, the United States, and

internationally. Interestingly, however, my work is not unique. At

least 14 journal articles and government reports have evaluated

mercury exposure from dental amalgam, and that is what is presented in this slide. The horizontal bars show the different estimates of exposure ranging from the minimum to the maximum.

The green circles represent the average as estimated by the different authors in those studies. The four studies at the top have

been authored by what I will term ‘‘pro amalgam’’ authors who

want to support the continued use of amalgam. They are totally out

of step with every other study that has been done on mercury exposure from amalgam, including a committee of the U.S. Public

Health Service, my own study for Health Canada, the World

Health Organization, Tom Clarkson, who is one of this country’s

foremost mercury researchers, and other authors from Europe.

Therefore, the fact that mercury exposure occurs and the likely

levels of that exposure throughout the population are not in doubt.

Other than my own work, what every other report or article on

mercury exposure from dental amalgam failed to do was ask the

question: So what? What does that exposure really mean? One answer to that question is achieved by comparing the levels of amalgam related exposure to what is deemed to be a ‘‘safe’’ or reference

exposure level. These are represented by the red vertical bars in

this graph. Such toxicological benchmarks are routinely prescribed

by the U.S. EPA, again amongst other agencies. And when the

mercury exposure from amalgam is compared to what is deemed to

be a safe exposure level by the EPA, it is apparent that dental

amalgam leads to excessive exposure in a very large proportion of

the United States and Canadian population. All exposure represented by those horizontal lines that go passed the red bar to the

right are exposures that exceed what the U.S. EPA calls a safe

dose. And in fact, if a Superfund site is contaminated with mercury, the exposure to residents around those sites cannot exceed a

dose equivalent to that red bar. So the exposure that occurs from

dental amalgam exceeds what would be permitted at a Superfund

site.

In my own assessment of risks on behalf of Health Canada, I

concluded that a more appropriate safe or reference dose is some

4 times lower than the reference dose established by the EPA. Further, from the analysis prepared on behalf of Sweden, it was apparVerDate 11-MAY-2000 10:06 Jun 17, 2003 Jkt 000000 PO 00000 Frm 00042 Fmt 6633 Sfmt 6633 D:\DOCS\84699.TXT HGOVREF1 PsN: HGOVREF1
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ent that the frequency of both neurological impairments and subtle

kidney effects increases with increasing dose, but still well within

the range that results from the presence of dental amalgam fillings.

The science upon which the U.S. EPA based their safe or reference exposure level for elemental mercury is quite dated. The

most recent article on neurotoxicity that is cited on their IRIS data

base is 1993. The keystone paper dates from 1983. This agency has

so far failed to update that reference level to reflect and include

any new science on the neurotoxicity of mercury vapor that has

been published since 1994, and there are a lot of studies. In my

submission I have listed many of them. It is apparent from that literature that neurological effects occur at levels of exposure much

lower than believed 7 years ago.

Mercury from amalgam crosses the placenta and contaminates

the unborn fetus, in proportion to the number of amalgam fillings

in pregnant women’s teeth. Yet, no research has attempted to identify a safe dose, if one exists, for elemental mercury in an unborn

child. Mercury from amalgam contaminates breast milk, in proportion again to the number of amalgam fillings in nursing women’s

teeth, and amalgam fillings may be placed into the teeth of children as young as 3 years old. Young children are a population

group whose central nervous system is still developing and in

whom neurological toxins such as mercury are more harmful than

in adults. Again, however, we do not know what effects this exposure might be causing.

Several countries, including Canada, Sweden, Norway, Germany,

and Austria, have now taken or initiated steps to reduce or eliminate the use of amalgam as a dental restorative material. Canada

has identified an obligation of informed patient consent and has

made a series of recommendations regarding in whom amalgam

should not be used. Identified groups include pregnant women,

children, and persons with kidney diseases, among others. In Sweden, with a national socialized dental health care program, the

placement of amalgam fillings is no longer funded.

The Superfund program in the United States does not permit as

much mercury exposure to residents living near those sites, as I

have said previously. Yet the place of dental amalgam into the

human body is still permitted, if not promoted, despite the fact that

those exposures exceed what a Superfund site would be permitted

to occur from what is classified as a hazardous waste.

In both the United States and Canada, efforts are now underway

to force major industries, particularly coal-fired electrical generators, to spend hundred of millions or perhaps billions of dollars to

reduce or eliminate mercury emissions. The reduction in mercury

emissions to the environment is a worthwhile cause worthy of your

support. However, the reductions in mercury emissions that will result from those massive expenditures will do nothing to reduce

mercury exposure in the population, not as long as dental amalgam, the primary source, is still in use. Industrial emission reductions will reduce slightly mercury levels in the atmosphere and,

with time, the environment in general, but exposures in the general population will change only marginally, if at all, since their

main source of exposure is planted directly in their teeth.

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If the desired goal is to reduce mercury exposure in the U.S. population, then massive action on minor contributors to that exposure

will be totally ineffective. Dental amalgam use must be reduced or

eliminated if a significant reduction in mercury exposure in the

U.S. population is to take place. Thank you very much.

[The prepared statement of Mr. Richardson follows:]

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Mr. BURTON. Thank you, Dr. Richardson.

Dr. Fischer, how are you?

Mr. FISCHER. Great. How are you?

Mr. BURTON. You are recognized.

Mr. FISCHER. Good morning, Mr. Chairman, members of the committee, and guests. My name is Rich Fischer. I am a dentist. I have

been practicing for 30 years. Over 20 years ago, based on information available at that time, I made an ethical decision to stop using

mercury in my practice. Dental amalgam, or silver mercury fillings,

whatever you would like to call them, contribute more mercury to

the body burden in humans than all other sources, including dietary and vaccines put together. These fillings contain 50 percent

mercury, which is more neurotoxic than lead, cadmium, or even arsenic.

To put this in perspective, the amount of mercury contained in

one average size filling exceeds the U.S. EPA standard for human

exposure for over 100 years. Put in other terms, it takes only onehalf gram of mercury, the amount in one filling, to contaminate all

fish in a 10-acre lake.

Mercury vapor escapes from dental amalgam fillings and is readily absorbed into the body. It accumulates in all body tissues and

has been shown to cause pathophysiology, which means abnormal

changes in the way our organs function. Furthermore, in the case

of pregnant women with mercury fillings, the mercury readily

passes from her bloodstream through the placental barrier and accumulates in the developing fetus. Mercury from dental amalgam

has also been shown to concentrate in mother’s milk, providing not

only a prenatal, but a perinatal and a postnatal exposure for the

developing child whose immune system and central nervous system

are exquisitely vulnerable to this poison.

Scrap amalgam mercury, that unused portion of the filling material remaining after the filling is made, must by law be handled as

a toxic waste disposal hazard. It cannot be thrown in the trash,

buried in the ground, or incinerated. Yet, some will justify storing

this same mixture in people’s mouths just inches from the brain

stem and declare it harmless. That just does not make sense to me.

Governments of six other countries, including Canada, Germany,

and the United Kingdom, have placed restrictions and/or issued

advisories against the use of mercury in dental fillings, particularly

in children and pregnant women.

In addition to the direct exposure to humans from dental fillings,

there exists a secondary route of exposure from dental offices. Published research shows that between 14 percent and 75 percent of

the mercury found in municipal waste waters originate from dental

offices. This poison finds its way into our rivers and oceans where

it contaminates fish as well as the environment.

There is not scientific debate over the following facts regarding

mercury from dental fillings:

One, mercury is more toxic than lead, cadmium, or even arsenic.

Two, mercury escapes from dental amalgam fillings continuously

as a vapor.

Three, some 74 to 100 percent of inhaled mercury vapor is absorbed into the human body.

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Four, inhaled mercury vapor from dental fillings accumulates in

the body to levels which cause pathophysiology.

I would like to direct your attention to the graph, please. The

graph represents data on mercury intake for the unborn fetus and

newborn. On the left here, this is the fetus, this is the first 9

months of life for the newborn, and this is the second 9 months.

I have broken this data down into those three equal time periods.

Again, these data are taken directly from published studies by

mercury toxicologists, not from dentists publishing in dental journals, in the World Health Organization. The intake data again is

divided into three intervals of 9 months each. The red indicates

mercury intake into the fetus and the child from dietary sources.

The black represents intake into the fetus from the mother’s fillings. The blue represents mercury intake to the child from vaccines. And the green represents the EPA upper limit of exposure

for adults. We have no standard for children or fetuses.

Any toxicologist will tell you that the larger and the earlier the

absorbed dose of a poison the greater the degree of damage. The

FDA has very wisely been looking at this tuna fish, swordfish,

shark situation and advising pregnant women not to be eating

those fish because of the dietary intake. I submit that the big one

has gotten away. They have not dealt with the issue of mercury

from amalgam, which is the earliest and the largest insult to the

child.

Also in my testimony there is a list of bibliography which show

that there are a number of human and animal studies published

in peer reviewed journals demonstrating the transfer of mercury

from amalgam fillings of pregnant females into the brains of unborn babies. There are no studies that contradict those findings.

You have heard a lot of science already this morning. I would tell

you that this issue is really not that complicated. The Environmental Protection Agency says that amalgam is a toxic waste disposal hazard before we put it into the mouth, it is a toxic waste

disposal hazard after we take it out of the mouth, and it does not

take a genius to figure out what it is in the mouth. Thank you.

[The prepared statement of Mr. Fischer follows:]

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Mr. BURTON. Thank you, Dr. Fischer.

Dr. Mackert.

Dr. MACKERT. Mr. Chairman and members of the committee, my

name is Rod Mackert. I am a dentist, I hold a Ph.D. in material

science, and I am a professor of dental materials at the Medical

College of Georgia School of Dentistry, and a member of the ADA

Council on Scientific Affairs. I speak on behalf of the more than

140,000 members of the ADA, the voice of more than 70 percent

of the Nation’s dentists. I am grateful for this opportunity to discuss dental amalgam, which increasingly is a subject of controversy, the discussion often marked by half-truths and misinformation.

I want to begin by stating categorically that dental amalgam is

a safe and effective treatment option for dental decay. I also want

to clarify the ADA’s role. It is not our intention to advocate one restorative material over another. We are here to attest to the safety

of dental amalgam. Our purpose is also to help dentists and patients understand all of the appropriate treatment options that are

available to fill cavities, to provide that scientific basis for professional choice of safe materials, and to defend the rights of dentists

and their patients to make informed choices among those safe options. And the vast majority of American dentists support us in

that purpose.

The ADA wants dentists and patients to understand dental treatment. I call your attention to the chart on restorative materials

that is in the materials that we have provided, which the ADA prepared to help dentists understand the various restorative options.

Amalgam is, by far, the most thoroughly researched and tested restorative material among all those that we dentists use. That is

why we oppose any legislative or regulatory action to limit its continued appropriate use.

One of the principal difficulties in designing a study on low-dose

neurological effects of any substance is identifying an appropriate

control group. To be valid, such studies must compare apples to apples. In this light, a particularly important study population is that

of the Swedish Adoption Twins Study of Aging, or SATSA, conducted by the Karolinska Institute which awards the Nobel Prize,

which evaluated twins reared apart and control twins reared together. A total of 587 subjects with mean age of 66 years were

studied. The authors concluded, ‘‘This study does not indicate any

negative effects from dental amalgam on physical or mental health

or memory functions in the general population over 50 years of

age.’’

A 1998 multi-center study by Amelcart and colleagues examined

4,787 patients to determine whether there is a difference in symptoms between patients with and without amalgam fillings. They

concluded, ‘‘Based on the present results, the first question of the

study, whether patients with amalgam fillings differ from patients

without amalgam fillings in regard to clinical symptoms, has to be

answered with a clear no. Additionally, there was no quantitatively

assessable relationship between the presence or intensity of special

symptoms and the number of amalgam surfaces.’’

Many other human studies have investigated the possible relationship between dental amalgam and Alzheimer’s disease, mulVerDate 11-MAY-2000 10:06 Jun 17, 2003 Jkt 000000 PO 00000 Frm 00062 Fmt 6633 Sfmt 6633 D:\DOCS\84699.TXT HGOVREF1 PsN: HGOVREF1
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tiple sclerosis, adverse pregnancy outcomes, reduced immune competence, impaired kidney function, or other adverse health effects

and they have found none. This is not to say that we consider the

book closed. Significant research about dental amalgam is ongoing,

most notably two major studies supported by the National Institute

of Dental and Craniofacial Research which you will hear about

from the next panel. We enthusiastically support these efforts and

any other legitimate research that deepens our understanding of

the science behind dental practice.

Simply put, mercury and dental amalgam are very different substances and using the terms interchangeably is misleading. When

mercury is mixed with other metals such as silver, copper, and tin

it forms inter-metallic compounds that behave completely differently from liquid mercury. The ADA is not alone in its position

that dental amalgam is safe and effective. The National Institutes

of Health, the U.S. Public Health Service, the Centers for Disease

Control and Prevention, the Food and Drug Administration, and

the World Health Organization, among others, have independently

reached the same conclusion.

The Alzheimer’s Association, the National Multiple Sclerosis Society, and the American Academy of Pediatrics all have explicitly

stated that there is no scientific evidence linking dental amalgam

with any known disease or syndrome that these groups track.

These organizations exist to understand these diseases and to advocate for those who suffer with them. They would not put their

reputations and the safety of their members on the line if they did

not agree with the majority of the scientific community that dental

amalgam is safe.

Dentists use amalgam because it is durable and easy to handle,

and therefore particularly useful for large fillings in back teeth on

which the bite pressure is greatest. It is especially valuable for

treating children and some disabled patients who have difficulty

keeping still because it can be placed quickly and does not require

a perfectly dry environment. Any dentist who has placed a good

filling in a moving 3 year-old can tell you how important this is.

It should go without saying that if we doubted the safety of

amalgam, its qualities, durability, ease of use, and cost-effectiveness would not matter. But this is not the case. Dental amalgam

is safe. We are greatly concerned that emotionally and scientifically

invalid reports about amalgam are confusing and even alarming

people to the point where they will not seek necessary dental care.

Postponing needed care only ensures that the problem will get

worse. Mr. Chairman, amalgam fillings are no threat to patients.

The real danger is untreated dental disease. Amalgam is an excellent material, albeit only one of many, in our fight against dental

disease. We urge you to consider only valid, scientific information

and take no action that would rob us and our patients of this valuable safe and effective therapy.

[The prepared statement of Mr. Mackert follows:]

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Mr. BURTON. Thank you, Doctor.

Mr. Stoute.

Mr. STOUTE. Mr. Chairman and members of the committee,

thank you on behalf of the National Dental Association for this opportunity to participate in today’s hearings. My name is Gregory

Allen Stoute, and I am currently serving as president of the National Dental Association. In addition, I am the Chief of Dental

Health Services for Harvard University in Cambridge, Massachusetts, I hold a Master’s of Public Health degree, and also serve as

a dental public health resident at Boston University Goldman

School of Dental Medicine, and serve as a Lieutenant Colonel in

the Medical Corps of the U.S. Army Reserves. I have practiced dentistry for 26 years.

The NDA represents more than 7,000 African-American dentists,

both in the United States and abroad. Since 1913 the association

has been dedicated to improving the health of the underserved and

promoting safety, prevention, quality, and equity in oral health as

well as general health. We are deeply committed to educating the

consumer and helping the public make informed choices based on

sound science.

Dental amalgam has been used as a restorative material in dentistry for over 150 years. In fact, the Food and Drug Administration stated that there is ‘‘more significant human experience with

dental amalgam than any other restorative material.’’ The National

Institutes of Health, the Centers for Disease Control and Prevention, the U.S. Public Health Service, and the World Health Organization have all said that dental amalgam is a safe restorative material.

I will simply state for the record that the NDA supports the conclusions of these organizations that we trust and believe amalgam

is a safe and effective restorative material. This belief underlies

our position. Dentistry is a profession built on sound science and

the NDA and our members are proud to be a part of that tradition.

Because we are firm in that belief, we will continue to advocate

vigorously for its continued availability as a treatment option.

All dental patients deserve the right to choose the most appropriate course of treatment. Eliminating dental amalgam as a restorative option precludes a dentist from offering his or her patients what may be the best choice from a clinical perspective. Dental amalgams are generally the preferred material for large fillings

in back teeth or in very deep fillings or fillings under the gum line.

Alternatives are often less effective and clinically contra indicated

in these situations. The NDA believes that all dental patients

should be provided with a full range of appropriate treatment options. Decisions on the most appropriate course of oral health treatment are best made by the dentist, in consultation with the patient, prior to treatment.

Dental caries, or tooth decay, are the most common chronic childhood disease, five times more common than asthma and seven

times more common than hay fever. Epidemiological evidence demonstrates that dental disease rates and dental needs are highest in

low-income and special needs populations—those who qualify for

Medicaid and the State Children’s Health Insurance Program

[CHIP].

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Access to quality dental care for all children, but especially poor

children, is a vital element of overall health care and development.

Unfortunately, children eligible for Medicaid and CHIP are three

to five times more likely to have untreated tooth decay and those

programs provide the only access to oral health care for a large

proportion of the economically disadvantaged. Very often these children have well-advanced dental disease. About 20 million children

are now covered under the Early and Periodic Screening, Diagnosis

and Treatment program in Medicaid. Nevertheless, only 20 percent

to 30 percent of Medicaid-eligible children see a dentist annually

and an unknown but much smaller percentage receives comprehensive care. CHIP extends dental benefits to millions more children,

but the law provides no mandate for dental services.

The NDA is concerned that the movement to eliminate amalgam

will create unwarranted public anxiety, increase disparities, eliminate access, and eliminate viable treatment options. We believe

strongly that all Americans are entitled to quality dental care and

we believe that these populations who have always received the

least care deserve to have all the dental care options available to

them. We feel that eliminating these options will place Americans

who are already disenfranchised at an ever greater disadvantage.

The NDA believes that all publicly and privately funded dental

plans should be required to provide reimbursement for all appropriate restorative materials. Many public and private sector dental

plans pay only for the most cost efficient restorative material. The

NDA believes that the patients and their doctors should have the

option to discuss and select the most appropriate course of treatment. These discussions would include the type of materials to be

used and the services to be rendered, as well as other considerations such as cost, durability, and aesthetics.

The NDA, along with the National Medical Association, opposes

eliminating dental amalgam as an option for dental patients because we believe this would decrease access and increase disparities.

By the way, I have spoken directly with Kweisi Mfume, the

president and CEO of the NAACP, and he states that, ‘‘following

delegate vote at our annual convention, our association does not

formally adopt any resolution unless it is approved by the national

board of directors, which has not met as of yet.’’

Also from their health division and the health committee, it

states that they both felt that this resolution was premature because ‘‘the science is still not available yet to confirm the need to

support the Watson-Burton bill to phaseout all mercury in dentistry within the next 5 years.’’ And likewise, getting the State legislators to develop similar legislation is too soon for that as well.

Thank you very much.

[The prepared statement of Mr. Stoute follows:]

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Mr. BURTON. Thank you. And I am sorry that I introduced you

as Mr. Stoute. I understand that you are Dr. Stoute as well. So

thank you.

Mr. Bender.

Mr. BENDER. Thank you, Mr. Chairman, members of the committee. My name is Michael Bender and I am the director of the Mercury Policy Project, an advocacy organization focused on reducing

exposure in emissions from mercury. While there has been considerable debate about the health effects of mercury fillings, little attention has been focused thus far nationally on dental mercury releases to the environment and their subsequent impacts. Yet there

is ample evidence from multiple government agencies that U.S.

dental mercury uses and releases is an environmental concern that

in turn presents health risks.

Due to human activities over the last century, mercury levels

have increased in the environment three-to fivefold and are responsible for between 50 to 70 percent of the total mercury loadings.

The most recent data from the Centers for Disease Control indicate

that 8 percent of women of reproductive age in the United States

have blood mercury levels that pose a risk to the developing fetus.

In June 2002, the Mercury Policy Project co-released a report

highlighting the pathways by which dental mercury is released to

the environment. Our study found that U.S. dentists are among the

top mercury users, on average consuming well over 30 tons of mercury per year, and are the single largest polluter of mercury to the

Nation’s wastewater. And while most human activities for mercury,

and their releases, have declined by 80 percent or more since the

1980’s, this has not been the case with the U.S. dental sector.

Approximately 70 to 100 million amalgams are placed in Americans each year by dentists, and 70 percent of these are replacement

fillings. Extracted amalgam materials are either rinsed down the

drain, usually to a municipal wastewater treatment system where

the heavy metal builds up in the sewage sludge, or deposited in

biomedical containers that are incinerated or placed in trash disposed in landfills or incinerators. When amalgam waste or mercury-laden sludge is incinerated, the mercury is instantaneously released to the air, contributing to both the regional and global mercury pollution. There is no debate on this point.

Studies by EPA and numerous municipalities document that

most wastewater treatment plans have high levels of mercury with

significant contributions from dental clinics. Moreover, conditions

within some dental unit holding tanks are perhaps favorable for

promoting methylation of mercury. Recently the Association of Metropolitan Sewerage Agencies evaluated seven major municipal

wastewater treatment plants to determine and quantify sources of

mercury coming into facilities. At all plants dental uses were identified as ‘‘by far’’ the greatest contributors to the mercury load, accounting on average for 40 percent of the load, more than three

times the next largest source. Yet wastewater treatment plants are

not designed to reduce mercury loadings to the environment. Consequently, all mercury either settles in the sewage sludge or passes

through the system to be discharged directly into a waterway.

However, there are cost-effective solutions readily available today

to significantly reduce dental mercury releases through employVerDate 11-MAY-2000 10:06 Jun 17, 2003 Jkt 000000 PO 00000 Frm 00094 Fmt 6633 Sfmt 6633 D:\DOCS\84699.TXT HGOVREF1 PsN: HGOVREF1
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ment of best management practices and installation and, I emphasize, proper maintenance of amalgam separators at dental clinics.

Several States, including Vermont and New Hampshire, are currently working with their State dental associations to foster this

approach. Furthermore, the American Dental Association has demonstrated a proactive approach through review of twelve amalgam

separators currently available in the United States today, finding

that all exceeded testing standards and that several of the units

tested exhibited removal efficiencies in excess of 99 percent.

Our June 2002 report describes successes throughout the United

States and in many countries who have worked cooperatively with

their dental sector in promoting installation of amalgam separators. A case in point is Canada which has recently developed nationwide standards to reduce dental mercury pollution. In response,

the city of Toronto, Canada, has substantially reduced dental mercury releases over the last year solely through the installation of

amalgam separators and employment of best management practices by 1,000 of Toronto’s dental practices. Data from Toronto indicate that the total average monthly mass of mercury in the sludge

has been reduced on average by 50 to 60 percent, and that is just

over the last several months.

In a second example, a 2001 study conducted cooperatively between the Minnesota Dental Association and the Metropolitan

Council Environmental Services quantified sludge mercury reductions at two wastewater treatment plants before and after amalgam separators were installed in dental clinics. The study found

significant reductions of mercury loadings from dental clinics of between 29 to 44 percent at the two wastewater treatment plants.

In sum, employment of best management practices and installation of amalgam separators would divert significant quantities of

mercury from ending up in the sludge at U.S. wastewater treatment plants and reduce disposal into landfills and incinerators and

reduce environmental releases and the subsequent risk to humans

from this dangerous toxin. Unfortunately, at this time less than 1

percent of dentists nationwide have installed amalgam separators.

Based on conservative estimates, the costs for U.S. dental clinics to

achieve these results would average approximately $600 per year.

What we are talking about is perhaps one to five visits from dental

patients would cover the cost for the entire year. This is clearly a

cost-effective solution to a serious environmental problem. Thank

you, Mr. Chair.

[The prepared statement of Mr. Bender follows:]

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Mr. BURTON. Thank you very much.

Let me start the questioning by asking a question of Dr.

Mackert. I think you indicated that, and I cannot remember exactly

what you said, but you indicated there is no risk with amalgams

in the mouth. Why is it, as Dr. Fischer said, it is a toxic substance

before you put it in the mouth and it is a toxic substance after you

take it out of the mouth, but it is not a toxic substance while it

is in your mouth?

Dr. MACKERT. Well when amalgam is first mixed, for several

minutes after that it contains liquid mercury. The mercury reacts

with the silver and tin and other elements in the metal powder and

forms inter-metallic compounds which have completely different

properties than liquid mercury. So immediately before it does contain liquid mercury and that is why it would be a hazard at that

point.

Mr. BURTON. And it is soft when you are putting it into the

mouth?

Dr. MACKERT. That is correct.

Mr. BURTON. It still does have liquid mercury in it.

Dr. MACKERT. That is correct.

Mr. BURTON. So when you are putting it in the mouth it is toxic?

Dr. MACKERT. Well, it releases some mercury vapor.

Mr. BURTON. So when you are putting it in the tooth there is a

release of mercury vapor that the patient would be subject to?

Dr. MACKERT. A small amount of vapor. And this has been studied, how much is released when it is placed, and the amount is

small.

Mr. BURTON. You are saying when it gets hard in the mouth it

is safe?

Dr. MACKERT. Yes.

Mr. BURTON. OK. Now after the dentist takes it out of the mouth

it is still hard.

Dr. MACKERT. Correct.

Mr. BURTON. So why is it toxic now?

Dr. MACKERT. It is not toxic at that point.

Mr. BURTON. Well we just heard from Mr. Bender here that one

of the largest contributing factors in the toxicity of wastewater

treatment plants is the mercury, and that is something that has

been said all over the world. So if it is not toxic when you take it

out of the mouth, why is it toxic when it gets into the wastewater

treatment plant?

Dr. MACKERT. Well it is not toxic when it gets to the wastewater

treatment plant. The way that these are analyzed is to digest such

materials in nitric acid and you dissolve the mercury in nitric acid

or other harsh chemicals and measure the amount of mercury and

you just have a number there on your analysis that is mercury.

That does not mean that the mercury that is in amalgam is available to be absorbed into the water or dissolved into the water.

Mr. BURTON. I think we have a difference of opinion. So let me

ask you another question. If you have mercury in your teeth, does

it wear down over time?

Dr. MACKERT. Yes, it does.

Mr. BURTON. So when it wears down as you are chewing, where

does it go?

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Dr. MACKERT. The particles of amalgam are swallowed usually

and the absorption even of liquid mercury in the gut is very small,

people have estimated 0.01 percent as the amount of mercury that

is absorbed if you swallow liquid mercury in your gut.

Mr. BURTON. But the point is it does flake off over time and it

does go into your system, this mercury.

Dr. MACKERT. Well, not through swallowing. The amount of

swallowing—we have estimated this, Dr. Anders Berglund of the

University of Umea—the dissolution in swallowing is about 1

microgram per day, and this is in comparison to 5 to 6 micrograms

per day that we absorb from our food and other sources, not amalgam. So it is a small contribution.

Mr. BURTON. What about the mercury vapors?

Dr. MACKERT. Mercury vapor is emitted, and this has been

known since about 1979. Prior to 1979, the instruments that were

available for measuring could not detect mercury vapor coming off

of amalgam fillings after they had set.

Mr. BURTON. What does the vapor do when it goes into the

mouth?

Dr. MACKERT. The amount of mercury vapor that escapes from

the fillings when a person is breathing in through the mouth is absorbed and contributes to the total daily dose. From several different ways of examining how much that is, it is between 1 and 3

micrograms per day. I know Dr. Richardson showed a chart of all

these, but I have a paper from Dr. Clarkson, who he mentioned as

being acknowledged by both sides of this issue as an international

expert on mercury, and I just want to point out what he said in

a paper he published this year, entitled ‘‘The Three Modern Faces

of Mercury.’’ He pointed out the amount of mercury that is released, he said, ‘‘As discussed below, these are far below’’—talking

about the amount that is released from fillings—‘‘these are far

below toxic levels.’’ So here is the world’s expert on mercury.

Mr. BURTON. OK. Let me ask you this question. I have been told,

and I am not a scientist, but I have been told that mercury in the

brain has a cumulative effect, it builds up. In other words, if you

get a little bit in, it is hard for you to chelate it out of your brain

because of the fatty tissue in the brain. So even though the amount

of mercury vapor you are talking about might be very low, if you

ingest that, even part of it over a period of time, would it not have

a cumulative effective which could have a dilatory effect on the

brain?

Dr. MACKERT. Scientists have measured about how much mercury that is inhaled is partitioned, what we called partitioned in

the brain, and that is about 7 percent of the total that is inhaled.

That mercury has a half-time, which means over half of it will decrease, it will decrease to half its amount in about 21 days. This

has been measured by Dr. Clarkson’s laboratory and others. So all

the mercury that is absorbed is not retained. It is fairly rapidly excreted actually, I mean 21 days. There is another compartment

that indicates a very small amount, which it is difficult to pin down

exactly how much, but a small amount does accumulate. Dr.

Clarkson and others have pointed out that this is because it forms

compounds with the element selenium which he and others believe

that this is a biologically inactive form, it is very insoluble——

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Mr. BURTON. Well that is what he believes.

Dr. MACKERT. Well he’s the expert in the world on mercury.

Mr. BURTON. We have got a bunch of experts here.

Dr. MACKERT. Not of the calibre of Dr. Clarkson. In the area of

mercury, I do not think any of these people here would claim to be

on a calibre of Dr. Clarkson. We can ask them if they think they

are and they know more about mercury toxicity than Dr. Clarkson

does.

Mr. BURTON. Well, we’ll hear from them. I will let my colleague

here ask a bunch of questions in just a moment.

Dr. Stoute, one of the things that you said was that dentists

should provide a full range of options.

Mr. STOUTE. Correct.

Mr. BURTON. Why would it be wrong for all patients to know that

there is some concern and a divergence of opinion about amalgams?

In other words, if I go into your office and you are going to put a

filling in my mouth, what would be wrong with you telling me that

there is a divergence of opinion about whether or not the mercury

in an amalgam is a problem and say that I think it is safe, but

there is this divergence of opinion and there are other alternatives

you can use, like a composite, and it is going to cost more, but I

think you ought to know that. What would be wrong with that?

Mr. STOUTE. I do not see anything wrong with that.

Mr. BURTON. Do you do that in your practice?

Mr. STOUTE. Yes, we do. We offer options based on——

Mr. BURTON. Do you tell them about the divergence of opinion

and whether or not mercury does cause a problem in the mouth?

Mr. STOUTE. In most aspects, I would say in all aspects of dentistry we do that. Some people have concern about x-rays and we

inform them about x-rays.

Mr. BURTON. So you do that?

Mr. STOUTE. Yes.

Mr. BURTON. Well I would say that would be great if all dentists

did it so we would all know those things.

I saw you shaking your head and I am going to let you respond

to some of the things he said, and then I am going to let Dr. Norwood ask some questions.

Mr. RICHARDSON. In regards to what happens to mercury when

it is absorbed into the body, the half-life in the blood is approximately 45 to 60 days, not 21 days. The half-life in the brain is on

the order of 30 years, not 21 days. It accumulates there. There

have been studies done on cadavers and, in fact, the concentration

of the mercury in the brain correlates with the number of amalgam

fillings in the teeth of those cadavers, as it does in numerous other

tissues of the body. And, yes, it does accumulate in the brain, it

does get locked in. Once it crosses the blood-brain barrier it is converted to a different form by binding with sulfhydryl groups, not

with selenium, and once in that form it cannot cross back across

that blood-brain barrier and be taken out of the brain. So that is

why there is the prolonged 25 to 30 year half-life for concentrations

in the brain.

Mr. BURTON. Anybody else have any other comments real quickly

before we go to Dr. Norwood?

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Mr. HALEY. Yes. I have the highest respect for Dr. Clarkson, but

I would say that if you read Dr. Clarkson’s papers, he totally ignores synergistic toxicities. What we presented here today is you

cannot tell what level of mercury is toxic unless you know a lot of

things about the person, the concentration of lead they are exposed

to, cadmium, and certain other things. The potentiation of toxicity

is dramatic, and I do not think Dr. Clarkson would disagree with

me that what we have shown with the effect of mercury on the

neurons is a very significant find and that it really lowers the level

of mercury that would be considered safe for young infants to be

exposed to.

Mr. BURTON. OK. Dr. Fischer.

Mr. FISCHER. Thank you, Mr. Chairman. I would have one question to my colleague. When he says that the amount of mercury

vapor coming off the fillings is very small, I would like to know

what units ‘‘very small’’ would be, if we can get an idea of units,

and at what level would it be of concern.

Mr. BURTON. OK. Dr. Mackert.

Dr. MACKERT. There have been a number of different assessments of the amount of mercury vapor that comes off of fillings. I

believe looking at all the available literature, and I am familiar

with all of the studies that Dr. Richardson showed on his slide, but

in evaluating these, 1 to 3 micrograms a day for a person with an

average number of fillings is the amount that would be absorbed.

And this compares with 5 to 6 micrograms per day that people

would absorb from other sources, including seafood.

In terms of what would be a level of concern, the World Health

Organization published numbers along that line for people, the

most sensitive group in the population where the first sub-clinical

effects would appear, and it would take between 400 and 500 fillings, surfaces of fillings to achieve these levels with the release

rates that we know.

Mr. BURTON. Dr. Norwood, I know you have some questions. I

will let you take it now.

Dr. MACKERT. May I also comment on Dr. Richardson’s response.

Are you saying that the half-time of mercury is 30 years, the

amount of mercury a person takes in, half of that takes 30 years

for that to go away? Are you claiming that on the record?

Mr. RICHARDSON. I will submit to this panel a paper that documents the half-life of mercury in the brain as being on the order

of 25 to 30 years.

Dr. MACKERT. All of the mercury that is absorbed, is that what

you are stating for the record?

Mr. RICHARDSON. Yes.

Dr. MACKERT. You are sadly mistaken.

Mr. BURTON. If you have a position paper on that or some documentation, I would like to have it from both of you so we can look

at it. OK?

Dr. Norwood.

Dr. NORWOOD. Thank you very much, Mr. Chairman. I have got

so many questions I do not know where to begin.

Mr. BURTON. Well there are only two of us so I am going to let

you go for a while.

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Dr. NORWOOD. Thank you, sir. I want you to know that I recognize this is not my committee and I am going to mind my manners.

I really would not be this nice if this were a Commerce Committee

meeting. But having said that, Mr. Chairman, I was greatly and

personally offended by the remarks in the opening statement from

Congresswoman Watson and I would like your permission to respond to that in writing for the record rather than making a big

to-do about it right here.

Mr. BURTON. Sure. Without objection, that is fine, Doctor.

Dr. NORWOOD. Dr. Haley, you are a chemist. Yes or no?

Mr. HALEY. Yes.

Dr. NORWOOD. Do you have degrees in biology?

Mr. HALEY. I did 3 years post-doctor at Yale in physiology and

my major emphasis area in chemistry was in biochemistry.

Dr. NORWOOD. OK. I understand. You must be a smart guy because that is a hard subject.

Mr. HALEY. I enjoy it.

Dr. NORWOOD. Good. I see that you do. I noted, and I have no

idea whether your scientific work is correct or not, and would not

question it anyway at this point, but I did note that most of it was

about mercury, the toxicity of mercury.

Mr. HALEY. What I talked about today, yes. Most of my work is

not about mercury.

Dr. NORWOOD. What is most of your work about?

Mr. HALEY. About the structure and function of nucleotide binding proteins that regulate body functions.

Dr. NORWOOD. Thank you. I got you. [Laughter.]

But your scientific work today was about liquid mercury. And

our hearing really is about amalgam, a metallic compound that

varies in percent but is at least 50 percent silver. So I do not question you, I bet you are right about the toxicity of mercury. But that

is not what we are here about. We are here about the possibility

of considering banning a major restoration material in this Nation

that will affect dental health. So we thank you for being here, mercury you may be right on, you may be right about the environment,

but we need to talk I think about what we are here about, which

is the amalgam filling.

It is clear to me from my work in the Commerce Committee with

the EPA that there are two or three known things. No. 1, you can

buy a scientific report saying anything you want to say. It just does

not matter. Whatever the opinion is that you want you can get it

paid for and get it done. I have seen that for 8 years in the EPA.

So I do not know who is right or who is wrong about the science.

I tend to think probably Dr. Clarkson is one of the world’s foremost

toxicologists in mercury. Do you still stand by that, Dr. Mackert?

Dr. MACKERT. Yes, I do.

Dr. NORWOOD. Do you agree with that, Dr. Haley?

Mr. HALEY. Yes, I mean he works primarily on methyl-mercury.

And to say that he would understand the toxicity and medical effects of mercury any better than any other well-trained bio-chemist, I would not give him—it is the area he worked in. But it is

something you teach to freshman——

Dr. NORWOOD. That is his area of specialization, like yours is

whatever that long list was?

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Mr. HALEY. He mainly works with methyl-mercury. Most of the

research I have read from Dr. Clarkson’s laboratory has been on

the mercury that comes from fish, not from amalgams.

Dr. NORWOOD. So he is an expert like all of you are experts, for

which nobody here dare define the word ‘‘expert?’’

Mr. HALEY. Probably. But I would point out one thing. We did

talk about amalgams. I get the same effect if I take an amalgam

made outside the mouth or in a tooth that has been given to me

by a dentist, if I drop it in water and I take that water after a period of time, and I showed that on the slides, and add that to brain

tissue enzymes or neurons in culture, it is toxic. So the amalgams

release mercury. And I tell you the problem here, which I would

challenge you and Dr. Mackert, let’s make 1,000 amalgams outside

the mouth and send it to Cal Tech and Harvard and the major

science institutions in the United States and let’s live with how

much mercury, let’s determine how much mercury comes out of

amalgam with no brushing, brushing 1 minute a day, and——

Dr. NORWOOD. Dr. Haley, I do not know that test has not been

run. I do not know that study has not been run. Are you telling

me you know of every study ever done with amalgams?

Mr. HALEY. No.

Dr. NORWOOD. Of course you do not.

Mr. HALEY. I am telling you that I have done it in my lab and

I get results that totally disagree with what Dr. Mackert says.

Dr. NORWOOD. Dr. Mackert, do you want to respond to that?

Dr. MACKERT. There is a big difference in doing a study in a lab

in a petri dish and doing human studies. Always the first step is

you look in the laboratory study, then you look in animals, and

then you look in humans. All the studies that I referenced today

were in humans. If these theoretical possibilities Dr. Haley has

raised were true in actual fact, then we would see them in these

human studies that have been done, and we do not.

Mr. HALEY. This is not theoretical. This is absolute——

Dr. NORWOOD. Excuse me. We need to have order. It seems to

me that it is hard to refute that only the EPA, who I have mentioned earlier is the one who buys the studies they want, is saying

that amalgam is toxic and we cannot get the CDC or the FDA or

the Public Health Service or the World Health Organization—I

mean, come on, are these people—I am not asking a question just

making a statement. [Laughter.]

I saw you warming up. I am going to ask you a question in just

a minute. It seems to me all of these people are not in cahoots with

the ADA. I do not believe they are. And this all says to us that we

do not really know that you are right at all about what you are

saying about the toxicity. People like me know what happens if you

are wrong and you get rid of this restoration, which in many cases

nothing else we have today will work. So I am just asking you to

be just sort of real careful with what you are saying now.

Dr. Haley, Dr. Linder asked me to ask you a question, and I am

not sure if he wanted to know this on a personal basis or just wanted to know in general. But he wants to know if there have been

any studies that show a higher incidence of Alzheimer’s disease in

retired dentists.

Mr. HALEY. There have been no studies done.

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Dr. NORWOOD. Anybody know of any?

Mr. HALEY. I do not know of a one. I do not know of a study.

This is a thing that says there is no proof of amalgams being toxic

or being dangerous or causing disease. There is no proof that it

does not.

Dr. NORWOOD. I understand. But there is absolute proof of the

damage done to the dental health of this country if you eliminate

it. I can tell you about that. I know something about that.

Dr. Mackert, next year I will have been a member of the ADA,

American Dental Association, for 40 years and I can guarantee you

they do not gag me on anything or I would not have paid my dues.

I would have just said good-bye and leave. Are you aware of any

gag rules in our Code of Ethics about talking to our patients?

Dr. MACKERT. No, I am not. In fact, the ADA encourages dentists

to discuss treatment options with patients. The ADA is concerned

that they not misinform patients on this or any other issue and encourage patients to subscribe to treatments that are not in their

best interest. They would certainly be opposed to that.

Dr. NORWOOD. Well I feel fairly certain that there are not any

gag rules. And if there were, we are an ornery group, dentists are,

and we would not pay them any attention anyway.

Most of us, Mr. Chairman, do talk to our patients about what

their alternatives are. Most patients do not want to sit there and

have me or any other practitioner respond to them on the details

of what is in, for example, amalgam fillings, although none of us

that I ever knew of would—you know, what the heck, if you do not

want amalgam, that is OK. I used to make a lot of money using

gold, probably the best restoration known to man. The only reason

we do not use it all the time now is because if we did another 30

percent of Americans would not be able to go to the dentist. That

is why we do not do it. That is the restoration of choice for us.

Part of our job is to treat Americans and we have to be very concerned about the cost because in dentistry, unlike medicine, thank

God, we do not have the Federal Government funding everything

that we do. People pay out of their own pockets. And we have to

keep that in mind if we want them to be treated. And that is really

what we are there for is to treat those patients. Now if you want

to tell a patient they need to have all their amalgam fillings taken

out so you can put in all new fillings, I would not lose, I would not

do badly in that arrangement to tell you, sit down, let’s take them

all out and do them all over again. We are a capitalistic country;

I am going to make a little profit on every one of them I take out

and every one of them I put in. So it is not that we mind doing

that. If that is what a patient wants us to do, let’s do it, although

I would question it.

Dr. Fischer, I want to ask you about that. What I know of you

is you are a really nice guy, a good guy, concerned, and really believe this honestly. But let me ask if I could just yes or no questions. You talk about the danger to children from dental amalgams.

Does the American Academy of Pediatrics agree with you? Just yes

or no.

Mr. FISCHER. I do not know. About what?

Dr. NORWOOD. Whether dental amalgam is dangerous to children.

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Mr. FISCHER. Did they say that? Is that what you are asking me?

Dr. NORWOOD. No. You believe that, don’t you?

Mr. FISCHER. I believe it is dangerous to some children and to

some people, yes.

Dr. NORWOOD. Does the American Academy of Pediatrics agree

with you?

Mr. FISCHER. As I say, I do not know what they say about it.

Dr. NORWOOD. Well you ought to, it seems to me.

Mr. FISCHER. I am not a pediatrician.

Dr. NORWOOD. No, I know, nor a physician.

Mr. FISCHER. Right.

Dr. NORWOOD. But if you are going to tell people this material

is dangerous, it should be I think of interest what the entire medical community that treats children think.

Next question. You talk about a relationship between dental

amalgam and autism. Yes or no, does the Autism Association agree

with your position on dental amalgam?

Mr. FISCHER. First of all, I do not tell patients it is dangerous.

You asked me if that was my opinion, and it is. Do I tell that to

patients? No, I do not. So let me clarify the first question.

Dr. NORWOOD. You do not tell patients that you are concerned

that they should not have dental amalgam, you just do not give

them the option?

Mr. FISCHER. I do not give them the option because I do not want

to expose the patients, my staff, or myself to the material. So that

is an option we do not give. If they want it, we refer them out for

that. I do not do root canals either, we refer them out.

Dr. NORWOOD. Do you basically think then that there is a negative relationship between dental amalgam and autism, patients

with autism?

Mr. FISCHER. Again, I am not a physician and I cannot make a

medical diagnosis. But from the American Academy of Pediatricians, they say in one of the conclusions in this report, ‘‘Mercury

in all its forms is toxic to the fetus and children.’’

Dr. NORWOOD. Of course, mercury. Who the hell would disagree

with that. We are not talking about mercury though. I would have

loved to have brought some mercury and put it out on that table

and then put a big wad of amalgam and ask you to pick each of

them up. Have you ever tried to pick up mercury?

Mr. FISCHER. OK.

Dr. NORWOOD. Me too. It is not easy.

Mr. FISCHER. The point being?

Dr. NORWOOD. The point I am making to you is there is a difference between mercury and amalgam.

Mr. FISCHER. Are you saying that there is no mercury in amalgam?

Dr. NORWOOD. Did I say that?

Mr. FISCHER. No, but——

Dr. NORWOOD. I sure didn’t.

Mr. FISCHER. OK.

Dr. NORWOOD. Now since I am going to ask the questions, let me

go to the next question. You talk about a relationship between dental amalgam and Alzheimer’s disease. Does the Alzheimer Association agree with you on your position on dental amalgam?

99

Mr. FISCHER. I did not speak about Alzheimer’s disease.

Dr. NORWOOD. Do you have a position on that?

Mr. FISCHER. No, I am not a physician or a neurologist.

Dr. NORWOOD. Did you have a position on that, Dr. Richardson?

Mr. RICHARDSON. No. It was Dr. Haley who spoke on Alzheimer’s.

Dr. NORWOOD. Do you have a position on that?

Mr. HALEY. Yes. I think absolutely you can say that exposure to

mercury would exacerbate the clinical condition we call Alzheimer’s

disease since it causes all the aberrant biochemistry and hallmarks

to be produced.

Dr. NORWOOD. And does their association agree with you?

Mr. HALEY. I have never talked to them. But they are just a

group of lay people. They are not scientific body. So there are a lot

of committees who do not know anything about this.

Dr. NORWOOD. How do you know they are a group of lay people?

Since you have never talked to them, I would like to know how you

know that.

Mr. HALEY. I read their literature, I know when they are out

raising money, I talk to the people at conferences that have Alzheimer’s booths.

Dr. NORWOOD. Well have you ever mentioned to them, hey, guys,

you ought to be on my side and be against dental amalgam, this

is real bad for Alzheimer’s and your association?

Mr. HALEY. Yes, I have. I sent them a letter a long time ago.

Dr. NORWOOD. And do they agree with you?

Mr. HALEY. No, they did not fund me.

Dr. NORWOOD. Thank you. Multiple sclerosis, that society does

not agree either. Do you ever advise your patients, Dr. Fischer,

with multiple sclerosis and other diseases that they ought to have

all of their amalgam fillings removed?

Mr. FISCHER. I am glad you asked me the question because the

answer is, no, I have never advised any patient to have their amalgams removed. When they come to me and ask me to do that, even

if it is based on a referral from a physician, we explain the options

to them—I give them the ADA materials without any references to

safety but they say it is safe and it is inert. We give them that material as well as some of the scientific references and then we let

them make their own choice. If they decide to get them out, we

have them sign an informed consent form after we fully inform

them. So, no, we do not recommend that they get them out.

Dr. NORWOOD. They said you were a good guy. But the question

is if patients come in and they have a mouth full of amalgam,

which you are on record very clearly thinking that is a very dangerous thing, do you advise them to remove their fillings?

Mr. FISCHER. No.

Dr. NORWOOD. That is an interesting concept. I will close, Mr.

Chairman, if I may, with one last question.

Dr. Mackert, it seems that if dental amalgam were banned,

frankly, the dental profession would make a lot more money because of the cost and the time that is associated with using other

restorative materials, which, by the way, Medicaid patients do not

all get amalgams. It was implied earlier that there was nothing

else that Medicaid patients could ever get. That is just not true. It

100

varies State by State. But tell me why you think the ADA is fighting so hard to keep amalgam as a restorative material.

Dr. MACKERT. In a number of situations, the ADA has advocated

positions that are not necessarily in the economic interests of dentists, and I think fluoride is a good example. This has been vigorously opposed by some groups but the ADA has been steadfastly

behind water fluoridation even though it actually works against the

economic interests of dentists. And I think this is a similar situation where there is no economic interest for the ADA or dentists

or even dental manufacturers who have told me, at least one manufacturer told me they actually make a bigger profit on the resin

composite materials than they do on amalgam. So they do not have

any vested interest in the continued use. It is just that amalgam

is one option. For example, if patients are allergic to ingredients in

the resin composites and we ban amalgam, what are they going to

use on those people? And people are allergic to things like hydroxy

ethyl-methacrylate which is used in dental bonding agents. It is

one of the most potent allergens used in dentistry. If we ban amalgam, then what are these people going to use for a filling?

Dr. NORWOOD. Mr. Chairman, people like myself who have spent

their life trying to take care of patients in dental health, we are

very concerned about this, and you pointed out some of it. We just

do not have some alternatives in some places. We would find alternatives or we would do something different if we knew for a fact

that this is harmful. What we do know is, my own personal experiences dealing and living with this and dealing with amalgam everyday, that it does not appear to be harmful to people that I am

aware of. And the other part of it is that if we knew it to be harmful, we would find something else. But we cannot do that with bad

science. We cannot do that with misconceptions in science that are

not always right.

Dr. Mackert, do you know who out there, for example, what are

the groups that are interested in banning dental amalgam? Who is

out there talking about this?

Dr. MACKERT. Well, there are several groups. One is called

DAMS, which I believe stands for Dental Amalgam Mercury Syndrome. Another is the IAOMT, which is International Academy of

Oral Medicine and Toxicology, which was founded by Murray Vimy,

a Canadian dentist in 1984, and almost the first action that group

took in 1984, before most of these studies were even conducted,

was to issue a press release calling for the banning of amalgam.

So almost the first thing they did as an organization was to call

for the banning of amalgam. So even before Vimy and Lorscheider

had done their studies, they were calling for the banning of amalgam.

Dr. NORWOOD. Who is that holistic dental society?

Dr. MACKERT. I am not sure.

Mr. BURTON. Dr. Norwood, we do have one more panel and I will

give you liberty to ask as many questions as you want. I would like

to ask just a few more questions of this panel.

Dr. NORWOOD. You have been very kind.

Mr. BURTON. You are a good man, even though we have a little

disagreement here.

101

Dr. Haley, what is the difference between dental mercury and a

jar of pure mercury? What is the difference as far as toxicity is concerned between a dental amalgam with mercury and a jar of pure

mercury?

Mr. HALEY. The mercury vapor coming off of liquid mercury and

the liquid vapor coming off of amalgam fillings is the same thing.

It is identical, absolutely chemically identical.

Dr. MACKERT. Could I comment on that? Are you saying that it

is the same amount that comes off?

Mr. HALEY. Of course not. When you form metallic bonds in

amalgam fillings and reduce the vapor pressure of the mercury and

it slows the evaporation rate. But what you have is allergens that

release mercury at a very low level for scores of years.

Mr. BURTON. That is the point I wanted to make. The mercury

vapor does come off of the amalgam?

Mr. HALEY. Yes.

Mr. BURTON. And it does chip away over time and you do consume that, it goes into the body and is excreted through the body.

Mr. HALEY. Yes, 80 percent of the vapor that is inhaled in the

body is retained by the body.

Mr. BURTON. You said 80 percent?

Mr. HALEY. Yes.

Mr. BURTON. OK. Now when it goes into the brain, I have been

told by leading scientists and doctors from all over the world that

the fatty tissue in the brain holds that in there more than any

other part of the body, so there is an accumulation of the mercury

over a period of time. Is that correct?

Mr. HALEY. The aspect is that mercury is what we call a hydrophobic gas, it would rather be in the fat. It will partition into fat

tissue versus water. Mercury is not very fond of water. However,

when it is in the brain it gets converted to the HG2+ and it binds

to proteins.

Mr. BURTON. So it sticks around for a long time.

Mr. HALEY. The fact is that versus, say, the HG2+, which does

not cross the blood-brain barrier very effectively, mercury vapor

does it with a great deal of ease. Once it is inside and it is oxidized,

the HG2+, then it does not come out.

Mr. BURTON. I have a couple of questions, and I do not know the

answer, but I do have two questions here real quickly. One is, Dr.

Norwood asked about an increase in the number of people I think

that have become autistic or hurt from mercury vapors and amalgams. I do not know what the relationship is there, but I do know

that we had 15 years ago 1 in 10,000 children was adjudged to be

autistic. Today, according to the Food and Drug Administration, it

is more than 1 in 250. We have had more than a 40fold increase.

Now that could be attributed to a number of things, but we do

know that mercury was in the vaccines and mercury was in the

amalgams of the mother and that may be a contributing factor. We

just do not know.

As far as Alzheimer’s is concerned, do any of you know whether

or not there has been an appreciable increase in the amount of Alzheimer’s?

Mr. HALEY. Yes.

Mr. BURTON. Can you give me statistical data on that?

102

Mr. HALEY. I would feel uncomfortable doing that, I just know

it is very significant. Every time you read a paper on Alzheimer’s

disease they bring up that there is something like I think 6 million,

somewhere in that range, of Americans today that have it and that

by 2040 it will be astronomically higher than that, I cannot remember the exact number, just that it is in the millions though.

Dr. MACKERT. Mr. Chairman.

Mr. BURTON. Yes?

Dr. MACKERT. I was just wondering if I could comment on that

question.

Mr. BURTON. Sure. Sure.

Dr. MACKERT. It is interesting that the use of dental amalgam

has actually declined over that same period that you mentioned on

autism and resin composites have increased till this year they are

more than half of the restorations placed. So, actually, if you are

looking for something to track—and I am not at all suggesting composites are behind it—but you would actually see the correlation

between composite and Alzheimer’s and autism rather than with

amalgam since amalgam use has declined.

Mr. BURTON. I did not say it was just from that source. When

Dr. Norwood and I get our flu shot, there is mercury in that flu

shot. A lot of people do not realize that and I do not think many

of our colleagues know that.

Dr. NORWOOD. It has affected us both too, I am pretty sure.

Mr. BURTON. Yes. Sure. [Laughter.]

But the point is there have been a number of things that could

be contributing factors to that and that is why I asked that question.

Is there a peer reviewed study that shows mercury fillings are

safe? Is there any peer reviewed study that you know of that shows

they are safe?

Dr. MACKERT. The difficulty in showing that any material is safe

is that you have to do several things. You have to identify potential

adverse effects, you can study, for example, multiple sclerosis or

even subtle changes in enzymes, and if you look at those in a

study, that is all you know is whether it causes that one thing that

you have studied. And there are thousands, if not millions, of

things that we could study that we could try to correlate with the

presence of amalgam fillings. Many of those studies have been done

but we have not looked at everything. It is not possible to do so.

We do not have enough money or enough people to look at everything. But the studies that have been done so far indicate that, as

the ones I have cited and others that are in our statement for the

record, these do not indicate any adverse effects from amalgam.

Mr. BURTON. Let me ask you one more question, and any of you

can answer this, and then we will get on with the next panel. I

would like to end with a little comment. Are removed mercury fillings a hazardous waste, Dr. Mackert?

Dr. MACKERT. According to the EPA test that is done to determine whether something is a hazardous waste, this was studied,

amalgam was subjected to this test and it does not qualify as an

EPA hazardous waste, according to my understanding.

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Mr. BURTON. Well why don’t we just flush it down the drains?

They do not do that anymore, do they? What does a dentist do with

an amalgam when he takes it out of a person’s mouth?

Dr. MACKERT. Well, I all the time get mailers and packages from

these different recycling companies that offer me money for amalgam scrap and other metal scrap. So many dentists, I do not know

what percentage, but many of them collect this and turn it in to

have the metals——

Mr. BURTON. I am not talking about many. I am saying when

dentists are taking a filling out of a tooth, are they allowed to just

flush it down the toilet or down the drain?

Dr. MACKERT. There are amalgam separators, there are traps

and stuff that collect various amounts of that mercury. This is not

an area of my expertise. There are others here I think that might

better answer that question.

Mr. BURTON. Does the ADA or any of its affiliate organizations,

such as the AD Health Research Foundation, hold any patents or

reap any financial benefit from mercury or amalgams?

Dr. MACKERT. Well amalgam was invented long before the ADA

was even established as an organization. So, obviously, the ADA

was not around when amalgam was invented. As with all different

materials, the Health Foundation works on improvements of materials, including amalgam. There were two patents issued I believe

in the 1980’s which were never exploited, never licensed.

Mr. BURTON. So they do not make any money off of amalgams?

Dr. MACKERT. They do not. In fact, the ADA Health Foundation

was the organization, an ADA scientists named Ray Bowen was the

man who invented the dental composite, the white filling that is

used.

Mr. BURTON. OK. OK. Let me ask Mr. Bender and Dr. Haley a

question. The amalgams, after they are taken out of the mouth and

disposed of, are they considered toxic by the environmentalist and

the EPA?

Mr. BENDER. I am not aware of the study that Dr. Mackert refers

to in terms of whether or not they pass or fail the EPA’s TCLP test.

What I do know is from an environmental standpoint dentists are

not regulated in terms of their disposal. That is one of the major

problems. What I do also know, I indicated in my testimony, that

approximately less than 1 percent of dentists in the United States

today have amalgam separators. In fact, talk about commissioning

studies to get the answers that you are looking for, the ADA recently commissioned with a group called Environ to basically come

out and say that amalgam separators were not a cost-effective approach to go.

Mr. BURTON. Dr. Haley, the amalgam, when they come out of the

mouth and are flushed down the toilet and down the drain and go

into the water——

Mr. HALEY. They place them in sealed containers to keep the

mercury vapor, when they are sitting in the dental office, from contaminating the air and making it unsafe for people to work.

Mr. BURTON. Dentists put them in a sealed container?

Mr. HALEY. In a sealed container under a liquid solution that

will bind the mercury vapor if it is released.

Mr. BURTON. Is that a common practice among dentists?

104

Mr. HALEY. I think so.

Mr. BURTON. Is that right?

Dr. MACKERT. That is. And the reason for that, as I mentioned

earlier, is that when the amalgam is first mixed it does release

mercury vapor for a short time until it completely sets. So that is

why it is placed under liquid, usually a photographic fixer or other

sulfur containing liquids are used.

Mr. HALEY. Research has absolutely shown that amalgams release mercury for years after they are hardened. Dr. Mackert is

just flat wrong in his assessment.

There was a study when they used a material called composel

and they showed that it released 43 micrograms per centimeter

squared per day and it did so consistently for 2 years. Unfortunately, this was put in the mouths of Americans. And the person

who published this research in Clinic Dental Research was from

Singapore University, it was not the FDA or the ADA. I do not

think they look at it. I had a debate with the dental department

at the University of Kentucky this Tuesday and I asked them, ‘‘Do

you have any devices in the school of dentistry that measures mercury in the air or in the water?’’ They did not have a thing.

Dentists are allowed to do things that the rest of us are not allowed to do. If I were to do experiments on mercury, I have to have

it picked up as a toxic waste. Mercury coming into my department

is classified as in the most toxic category of chemicals whereas the

FDA dental branch classifies it as a totally safe material, as safe

as a bedpan. There is a lack of common sense being applied here.

And that is what I am saying. Do not believe me, do not believe

him, make amalgams outside of the mouth, get a Government

group to go check the amount of mercury that comes out under abrasion, under heat, and then settle this. This is not rocket science;

this is simple stuff. And I know I am right and I know the amount

that Dr. Mackert says comes out of amalgam fillings is wrong, because if he talks about the amount that comes out per surface area

exposed, and if you look at the amount that is in the urine and you

multiply that by 9, because 90 percent of the mercury comes out

in the feces, you cannot even possibly account for that amount of

mercury with his values.

Dr. MACKERT. Let me just comment on that study. I know Professor Chou, he is a friend of mine, who published that study. It is

interesting, they only pick the one material that is not even sold

in the United States, never has been sold in the United States, the

composel that he mentioned, it is not a standard formulation of

amalgam at all. Even in that study that he mentioned it says, so

he could not be unaware of this, that it released much more mercury, in fact, 400 times more mercury into solution than any other

amalgam that was studied. So why does he pick that one amalgam?

Mr. BURTON. Let me interrupt here just a second. I think this is

a very interesting debate. Would the American Dental Association

and your association, Dr. Stoute, be willing to perform the kind of

test that he is talking about? In other words, make amalgams and

put them into different kinds of conditions, send them to major scientific research laboratories around the country—I would be very

happy to facilitate that—and let them come up with an answer to

105

this because the American people would like to know. Now if the

ADA says no, I would like to know why.

Dr. MACKERT. We are willing to fund any studies or——

Mr. BURTON. Are you willing to do that? Are you willing to make

the amalgams——

Dr. MACKERT. It has been done.

Mr. BURTON. It has been done?

Dr. MACKERT. Yes. The study that he mentioned talks about

other amalgams and they are 400 times lower than the one that

he happened to cite.

Mr. BURTON. The amalgams used here in the United States, the

amalgams that are used in dentists offices all across the

country——

Dr. MACKERT. The other amalgams that were in that study were

used in the United States.

Mr. BURTON. Would the ADA be willing to do a study where they

took amalgams, 100, 200, whatever it takes, make them, put them

under different conditions, send them to the various laboratories

around the country and let the American people know what the results are? Would they be willing to participate in that kind of a

study?

Dr. MACKERT. We would. But again, these studies have been

done. The study that he cited has that very data in it that he failed

to cite.

Mr. BURTON. If you would be willing to do that, that would be—

so you are speaking on behalf of the ADA that you would be willing

to do that?

Dr. MACKERT. We will respond in writing to that. You know, I

am a faculty member of the Medical College of Georgia, I do not

work for the ADA. I cannot tell you what the ADA——

Mr. BURTON. You are representing the ADA today.

Dr. MACKERT. Yes, I am. But I do not work for the ADA.

Mr. BURTON. Who would make that decision?

Dr. MACKERT. The Council on Scientific Affairs, of which I am a

member, I start my term in January.

Mr. BURTON. So you are a member of that. Would you recommend that they would do that?

Dr. MACKERT. Well, if we want to be cost-effective in our expenditures of research dollars, if something has already been done multiple times, then it is not cost-effective to do it once again. If that

information is not available in the literature, we would certainly be

very interested in pursuing that and funding that.

Mr. BURTON. I do not see why it would not be something that

you would want to do, because it would put an awful lot of this debate to rest.

Dr. MACKERT. It would never put it to rest because—I am sorry,

I keep interrupting.

Mr. BURTON. I just think it is something that would allay a lot

of people’s concerns and fears. Because Dr. Haley I think has said

very, very clearly that the amalgams outside the mouth are toxic,

they release toxic vapors.

Dr. MACKERT. But they are not toxic. Toxic means it causes demonstrable adverse health effects, and they do not. There are studies that have shown that, studies that have looked at this, thouVerDate 11-MAY-2000 10:06 Jun 17, 2003 Jkt 000000 PO 00000 Frm 00113 Fmt 6633 Sfmt 6633 D:\DOCS\84699.TXT HGOVREF1 PsN: HGOVREF1
106

sands of subjects, all the things that I mentioned, Alzheimer’s disease, multiple sclerosis, adverse pregnancy outcomes. You can always think of more symptoms to look for but we have looked at the

major ones people have brought up as adverse health effects, reduced immune competence, kidney function, all these studies have

been done and looked at it and compared groups of people with and

without amalgams and they do not find any difference.

Mr. BURTON. OK. Well you are not for doing the study then? You

do not want to do it?

Dr. MACKERT. If the study has already been done and we have

the data in the literature——

Mr. BURTON. Has that kind of study been done, Dr. Haley?

Mr. HALEY. Just one study he reported. When I bring up the aspect of the 43 micrograms, it is that here was an amalgam filling

that was used and it was placed in the mouth of Americans and

nobody tested it.

Dr. MACKERT. No, it was not.

Mr. HALEY. I have tested, and I teach a class called Mercury,

Science, and Politics, and I have students measure the amount of

mercury that comes out of amalgam fillings. And while it is not as

high as the composel, which is extremely high, it still is very significant. And when you brush it, it goes up to 43 micrograms per

centimeter squared. If you abrade the amalgam filling 30 seconds,

twice a day, you get a huge increase.

Now I know high copper amalgams release more mercury than

low copper amalgams. I have read all the stuff. What we have to

do is talk about the specific material that is being put in people’s

mouths and just test it. That is the only thing I think that is needed. If you are going to use it, test it and say how much comes out

just setting quiescently in a test tube in water, and then abrade

it, just brush it, and say how does it respond when you brush it

with say a medium bristle toothbrush, add heat to it like you are

drinking coffee and see does it increase it. You have got to do these

studies. And no, these studies have not been done.

Dr. MACKERT. Yes, they have.

Mr. HALEY. Where?

Dr. MACKERT. Anders Berglund, at the University of Umea in

Sweden, did exactly those things. He monitored patients every 30

minutes throughout the day, including all night——

Mr. HALEY. Not in a sealed container.

Dr. MACKERT. Let me finish. He had them drink coffee and, contrary to the allegations of the anti-amalgamists, it does not cause

an increase in mercury release. Many foods actually cause amalgam release to go down.

Mr. BURTON. OK. Let’s end this panel. Let me just say, and I

have all kinds of literature that we have studied and read, mercury

is a toxic chemical, mineral. Nobody has any doubt that if mercury

was lying on that table there, nobody would want to be messing

with it because it is toxic. It is in amalgams. It is in some of our

vaccinations. And in many people’s minds, mine included, there is

a substantial risk. I have had my amalgams out. I am going to get

even my capped teeth, the ones that have gold over them that may

have a filling in them, I am going to get those out because I just

do not want the risk, even though you would not agree with me.

107

If there is any doubt whatsoever, it seems to me that people

ought to err on the side of safety. And I think the American people

need to know at least that amalgams contain 50 percent mercury.

They do not know that. I did not know that and I am a fairly wellread person. I think if the American people were made aware, just

made aware of the fact that the amalgams contain 50 percent mercury, knowing even a small amount of what they do about chemistry and about the biology of the human body, I think an awful

lot of them would opt for another kind of filling.

It just seems to me—I understand that Dr. Norwood is going to

oppose this bill, it is probably not going to go anywhere—that we

need to have more hearings on this subject, and we will have more

hearings. This subject will be discussed and debated and it will be

illuminated. At the very least, the American people will know there

is mercury in fillings and they will be able to make an informed

decision on whether or not they want to have that in their mouth,

just like we have been trying to illuminate the issue of whether or

not there should be mercury in vaccinations for children. My

grandson got nine vaccinations in 1 day. He was a wonderful boy.

Two days later, 3 days later he became autistic and he is ruined

in part for life. He got 47 times the amount of mercury that is tolerable in an adult in 1 day and it made a big difference I believe

in his life.

So when somebody asks me should there be mercury in vaccines,

I say hell no. And if somebody asks me if mercury should be in

anything that goes into the human body, I am going to say I do

not believe so. I am a layman, I am not a scientist, but from what

we have heard at our hearings and from scientific research around

the world, I do not believe it should be in there. But at the very

least, I think dentists ought to inform the American people that

they are half mercury, and if the American people know that, I

think they will make the decision themselves.

With that, I think we ought to go to the next panel. Thank you

all very much. We appreciate your comments.

We will take a 5-minute break here, if you like, and I will come

right back.

[Recess.]

Mr. BURTON. The committee will reconvene.

We will now hear testimony from the second witness panel. I

would appreciate those individuals coming to the table. Dr. Lawrence A. Tabak, Director, National Institute of Dental and

Craniofacial Research, National Institutes of Health; and Dr. David

W. Feigal, Director, Center for Devices and Radiological Health,

Food and Drug Administration. I appreciate your being so patient

listening to all the discussion and debate.

Would you please rise and be sworn.

[Witnesses sworn.]

Mr. BURTON. Dr. Tabak, do you have an opening statement?

Mr. TABAK. Yes, Mr. Chairman, thank you.

108

STATEMENTS OF LAWRENCE A. TABAK, DIRECTOR, NATIONAL

INSTITUTE OF DENTAL AND CRANIOFACIAL RESEARCH, NATIONAL INSTITUTES OF HEALTH, BETHESDA, MD; AND DR.

DAVID W. FEIGAL, DIRECTOR, CENTER FOR DEVICES AND

RADIOLOGICAL HEALTH, FOOD AND DRUG ADMINISTRATION, ROCKVILLE, MD

Mr. TABAK. Thank you, Mr. Chairman, for inviting me here today

to discuss NIDCR-supported research on mercury in dental amalgam, a material used to restore teeth damaged by the effects of microbial infection or trauma.

The effects of elemental mercury exposure have been studied primarily in occupational studies, where the exposure levels have

been on the order of 100 to 1000 micrograms per liter of urine. Estimates of exposure from dental amalgam can range from 1.2 to approximately 20 micrograms per liter of urine, depending on the

number of tooth surfaces restored and the size of the restorations.

In the early 1990’s, the Assistant Secretary for Health charged

the PHS Committee to Coordinate Environmental Health and Related Programs to conduct a comprehensive assessment of the benefits and risks of dental amalgam based on peer reviewed scientific

literature. Their 1993 report concluded that scientific evidence does

not demonstrate that exposure to mercury from dental amalgam

poses a serious risk in humans. However, the Committee’s Subcommittee on Risk Assessment called for additional research to address whether dental amalgam creates a significant health risk to

individuals. the NIDCR responded in 1996 by launching two clinical trials designed to assess whether exposure to mercury in dental

amalgam in children is associated with adverse neurological, renal,

immunological, microbiological, behavioral, or cognitive effects.

These studies are comparing the possible health effects of amalgam with composite dental fillings over time. Only children who

did not have any prior fillings have been included as participants

in order to address the concern that any possible adverse health effects might have been caused by pre-existing dental restorations. It

is expected that both trials will be completed in 2006.

One clinical trial is being conducted by a group of scientists from

the University of Washington in Seattle in conjunction with a

group from the University of Portugal in Lisbon. 507 children between the ages of 8 and 10 years are participating in this trial.

Five primary endpoints are being monitored from baseline and at

1 year intervals: three neurobehavioral indices including combined

assessments of attention, memory, and motor domains; one neurological assessment involving nerve conduction velocity; and an endpoint aimed at assessing renal function. In addition, urinary levels

of mercury were assessed at baseline and are being measured at

each followup exam.

A second clinical trial is being conducted by a consortium of scientists from the New England Research Institutes, or NERI, in

Cambridge, Massachusetts, Forsyth Dental Clinic and Harvard

University in Boston, and the University of Rochester in Rochester,

New York. 534 children between the ages of 6 and 8 years requiring at least two fillings were recruited into this trial from sites in

the Boston/Cambridge area and in Farmington, ME. The trial is

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ditional tests of neuropsychological, cognitive and behavioral, and

renal functioning are also being carried out.

The conduct of both trials is overseen on an annual basis by an

independent Data and Safety Monitoring Board, the DSMB, consisting of experts in the fields of dental restorative materials, pediatric neurology, pediatric nephrology, neurotoxicology, cognitive

and behavioral development, heavy metal/environmental toxicology,

biostatistics and bioethics. The DSMB has met once a year since

the inception of the trials, and meets by teleconference on an asneeded basis, to review group distributions of endpoints and to

evaluate trial operations. Based on these data, the DSMB determines whether or not individuals are at increased risk, whether

the trials should be ended, and whether the results should be made

available to the public.

Over the course of the trials several children have shown higher

than acceptable urinary mercury levels. When retested, most values have been within the acceptable range. Also, some children

have shown changes in one or more of the neuropsychological

endpoints that caused concern and followup clinical examination by

the study teams. These changes, however, have not been limited

only to children receiving amalgam and, for the most part, the

problems identified seem to have existed prior to the entry into the

trial. To date, no harmful untoward effects attributable to amalgam

have been noted in either trial, and on each occasion the DSMB

has recommended that the trials be continued.

In summary, Mr. Chairman, available scientific evidence continues to indicate that dental amalgam is a safe restorative material.

Of course, I would be happy to respond to any questions you might

have.

[The prepared statement of Mr. Tabak follows:]

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Mr. BURTON. Thank you, Dr. Tabak.

Dr. Feigal.

Dr. FEIGAL. Mr. Chairman and members of the committee, I appreciate your invitation and this opportunity to discuss the issue

of dental amalgam safety.

Let me begin with a brief overview of FDA’s regulatory authorities over medical devices generally and how they have been applied

to dental amalgam.

The term ‘‘medical device’’ in the statute encompasses thousands

of health products, some simple and others quite complex. Dental

amalgam, as well as its components—dental mercury and the alloy

with which the mercury is combined—are medical devices.

The Medical Device Amendments of 1976 to the Federal Food,

Drug, and Cosmetic Act gave FDA specific authority to regulate the

safety and effectiveness of medical devices and provided a variety

of mechanisms with which to do so. These included the classification of medical devices into risk categories, medical device establishment registration, quality systems manufacturing requirements, and the control of the introduction of medical devices to the

market.

Devices on the market at the time of the 1976 Amendments were

assigned to one of three classes of risk to patients. Class I devices,

posing the lowest risk, are subject to general controls applicable to

all devices. Class II devices, which pose incrementally greater risk,

are subject to additional controls called ‘‘special controls’’ designed

to address the specific risks of the type of the product. Examples

of a special control that might be applied to a Class II device include conformance with mandatory performance standards and,

less often, clinical studies. The riskiest devices, such as some implants and life-supporting or life-sustaining devices, are placed in

Class III and require valid scientific evidence of safety and effectiveness before they can be marketed. The Act also authorizes the

agency to ‘‘reclassify’’ a medical device to a higher or lower regulatory class when warranted.

Amalgam has an extremely long history of use by oral health

care providers, well over 100 years. Amalgam consists of roughly

equal parts of mercury and amalgam alloys made from other materials such as silver, tin, and copper. Historically, mercury was regulated as a Class I device. Dental amalgam alloy was regulated as

a Class II because of potential risks from variations in the chemical

formulation of the alloy. The encapsulated form of the amalgam,

which consists of measured proportions of amalgam alloy and dental mercury, were never separately classified. However, because the

encapsulated amalgam is a combination of two classified devices, it

is regulated in the higher class of its components as a Class II device.

In the early 1990’s, the FDA became increasingly aware of consumer concerns about the safety of the mercury component in dental amalgam. At the direction of the Assistant Secretary for Health,

the National Institutes for Health, the Center for Disease Control,

and FDA conducted a comprehensive review of both the health

risks and clinical effectiveness of the product.

This extensive evaluation demonstrated that the clinical benefits

of dental amalgam outweighed the observable risks, specifically

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mild, transient allergic reactions among a very small percentage of

patients. In 1993, the Public Health Service issued a comprehensive risk assessment management plan developed with outside peer

review to ensure that the NIH, CDC, and FDA collaborated to advance the state of the science, and to keep dental professionals current on the latest scientific information about dental amalgam safety, and to maintain an appropriate level of regulatory control over

the product.

The PHS conducted followup reviews of the literature in 1995

and in 1997. And in 1997, FDA invited concerned groups to submit

scientific studies for review to FDA by toxicology experts and other

experts outside of FDA. Since 1997, we have reviewed more than

an additional 170 studies which, taken together, did not change our

risk profile for dental amalgam.

In addition to keeping abreast of the science here in the United

States, we and our PHS colleagues have aggressively pursued information about the risks of dental amalgams from public health

agencies and organizations around the world. To date, a review of

the risks and benefits of dental amalgams has not changed FDA’s

risk-benefit assessment.

We are planning to begin another review with NIH and CDC to

update the assessment of the scientific literature on the health effects of dental amalgam. Once again, this later effort will involve

experts from both the Government sector and the outside scientific

community and we will solicit broadly for information which we

should review.

Let me speak a bit about the current regulatory status of amalgam. There has been some confusion among those interested in this

issue about the regulatory status of dental amalgam and the purpose of a rule that the agency proposed last February. As explained

earlier, mercury, alloy, and encapsulated amalgam are all legally

marketed products. Mercury is a Class I device, amalgam alloy is

a Class II device, and the combination is regulated as a Class II.

In February 2002, FDA proposed a rule to bring all amalgam

products into Class II, requiring ingredient labeling and perform

conformance to international standards. Disclosure of amalgam ingredients will also help dental providers to quickly diagnose and

treat rare allergic reactions to amalgam components. Given the

high level of interest in this proposed rule, we twice reopened the

comment period, and we are now in the process of reviewing more

than 750 comments submitted to the docket.

In conclusion, Mr. Chairman, FDA is committed to monitoring

the scientific evidence closely relating to dental amalgam safety.

We will continue to exercise our regulatory responsibilities appropriately in accordance with the best available science. And we will

continue to work with the public health community to reduce the

incidence of dental caries and improve the quality of oral health

care.

Thank you again for this opportunity. I am happy to answer any

questions you or the members of the committee may have.

[The prepared statement of Dr. Feigal follows:]

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Mr. BURTON. Thank you, Dr. Feigal.

Mr. Gilman, do you have any comments you would like to make

before we start the questions?

Mr. GILMAN. Thank you for conducting this hearing. I am sorry

I had another engagement that delayed me from coming over. I

want to recognize the importance of your decision to hold hearings

on mercury levels in dental amalgams and commend your efforts

in investigating medical exposures to mercury and other potentially

toxic materials.

I think today’s hearing is important because it deals with mercury, a highly toxic element. Unlike other toxins, mercury is unable

to be filtered out or eliminated by our bodies; instead, it accumulates over time. For that reason, efforts have been made to reduce

the level of exposure of the public to mercury. Mercury thermometers have been phased out, and the FDA has issued warnings that

vulnerable populations such as pregnant women and young children should avoid consuming too much mercury-containing fish.

There is currently an ongoing debate of course within the dentistry community about the potential for harm from the dental

amalgams which contain mercury. And while the majority of dentists use such amalgams and see no long term harm in doing so,

a significant percentage are moving away from such practices.

So I look forward to being able to review all of the testimony that

you are taking today, and I again commend you. I do have some

questions after the panel has finished their testimony.

Mr. BURTON. Thank you, Chairman Gilman.

You said that the FDA has been following this and checking this

out for a long, long time. Can I ask you a couple of questions about

the history of the FDA and mercury fillings, this is from 1976 till

now?

Dr. FEIGAL. Yes.

Mr. BURTON. In 1976, Congress ordered the FDA to regulate devices. In 1986, Proposition 65 passed in California, I am sure you

are familiar with that. In 1987, the FDA classifies all dental fillings except encapsulated mercury amalgam. Is that correct?

Dr. FEIGAL. It was not specifically encapsulated but it was covered by the classification of its two separate components.

Mr. BURTON. Well is that a correct statement, the FDA classified

all dental fillings except encapsulated mercury amalgams? Is that

a correct statement?

Dr. FEIGAL. That is correct.

Mr. BURTON. OK. Why did they not classify that as well?

Dr. FEIGAL. To be honest, we do not know if it was an oversight

or if it was the intent to regulate the combination product by regulating its two components, both of which were classified. There is

no unclassified component in the product. But we actually have not

been able to reconstruct that history.

Mr. BURTON. Citizens groups sued the FDA for failing to classify

mercury amalgams in 1991 and 1993. In 1993, Public Health Service asked the FDA to classify mercury amalgams. In 1997, OSHA

backed off regulating dental offices because of FDA promise to classify. In 1997, FDA writes a letter again promising to classify mercury amalgams. And from 1990 to 2002, meanwhile the FDA prohibits other mercury containing items, including disinfectants, vacVerDate 11-MAY-2000 10:06 Jun 17, 2003 Jkt 000000 PO 00000 Frm 00133 Fmt 6633 Sfmt 6633 D:\DOCS\84699.TXT HGOVREF1 PsN: HGOVREF1
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cines, even horse medicine, there is still some in some vaccines.

But did you ever classify mercury amalgam?

Dr. FEIGAL. Dental mercury is classified as Class I and the alloy

has been classified as Class II, and the component is classified as

a mixture of two products, one of which is Class I and the other

is Class II, not separately classified. We have had petitions to

change the classification, but the product has been classified for

some time. I would have to get you the exact dates.

Mr. BURTON. It has been classified?

Dr. FEIGAL. Yes.

Mr. BURTON. It said that OSHA backed off in 1997 regulating

dental offices because of FDA promise to classify. And it says FDA

writes a letter in 1997 again promising to classify mercury amalgams. But you say it actually has not been done. You classified the

components but not the mercury amalgam itself.

Dr. FEIGAL. The manufacturers of the combination product where

the two are encapsulated together have been regulated since the

classification of Class I and Class II as a Class II product.

Mr. BURTON. What is a Class II product again?

Dr. FEIGAL. A Class II product is a product that has specific controls. So in the case of the alloy, the amalgam alloy, there are

international standard organizations, ISO standards and there are

ANSI standards on the compositions of alloys, recognized standards

for what those compositions can be, and they have to meet those

standards.

Mr. BURTON. OK. So does that mean that Class II would be considered a toxic substance or a possible toxic substance?

Dr. FEIGAL. Well, the risk classification is not actually based on

the toxicity of the compound in the absolute sense. It is based on

the risk in use to the patient. And so it is not based on environmental toxicity, on toxicity to animals, it is based on whether or

not it needs to have special controls in order to assure that the

product will be safe and effective as used. And in this case, the control is to know what is in the alloy.

Mr. BURTON. Do you have any idea how many micrograms of

mercury vapor is emitted by a filling in the day?

Dr. FEIGAL. We have reviewed the same studies that were discussed by the first panel and we have, as part of the process over

the years, gone over that literature and we understand that literature presents a range of values.

Mr. BURTON. A range from where to where?

Dr. FEIGAL. I would have to followup in terms of providing

that——

Mr. BURTON. We have somebody here that has a mercury amalgam. Don’t you have a device that measures the micrograms in it?

Can you do that for us while we are here? I would like for them

to have that information while they are here. I do not know how

you do that.

Mr. RICHARDSON. Someone here brought a sniffer.

Mr. BURTON. What was that?

Mr. RICHARDSON. Someone here has a mercury vapor sniffer.

Mr. BURTON. Right. If they would like to come up here and show

us, we would like to have that.

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Does the FDA take a position on the amount of mercury that accumulates in the brain and whether or not it is easily excreted

from the brain?

Dr. FEIGAL. The toxicology of chronic implants, like alloy, are

looked at through a series of standards that evaluate biomaterials.

And most of the evidence that we evaluate biomaterials with come

from animal data and come from special exposure studies in animals. Manufacturers are required to know the toxicology profile of

their products as part of the controls that they have over their

products. The risk is not assessed in terms of any absolute amount

or characteristic of the toxicology, but in the context of the risk and

benefits in clinical use.

Mr. BURTON. You were here for the previous panel.

Dr. FEIGAL. Yes.

Mr. BURTON. You heard some of the researchers, the scientists

that testified who said that when you brush your teeth, when you

chew, when you have hot coffee or a hot substance in your mouth

vapors are emitted, and when you chew some of it flakes off over

a period of time and goes into your body. Has there ever been a

study done on cadavers, people that have had a lot of fillings in

their mouths to see what the mercury content is in the brain, any

studies that you know of?

Dr. FEIGAL. The studies that they cited are the same studies that

we reviewed in our process of looking at the literature. How that

relates to our classification is to look at the product in actual use

and to look at the risk and benefit. All implants, including hip implants, jaw implants, that are made of metal have metals that

leech into the body, plastic materials have volatiles, and we assess

all of those exposures. It is not a question of whether or not there

is an exposure. The question is whether there is adequate evidence

that the exposure causes clinical——

Mr. BURTON. These other substances that you are talking about,

though, steel, plastic, they are not in the same class as mercury,

are they?

Dr. FEIGAL. There are problematic compounds that in very low

amounts—for example, there is cadmium in the alloys of hip implants.

Mr. BURTON. Cadmium, is that consistent with mercury as far as

toxicity?

Dr. FEIGAL. My point is that we——

Mr. BURTON. No, is it? Is it as toxic as mercury to the human

body?

Dr. FEIGAL. It has to be put in the context of the level of exposure and what the effect is and how that is offset by the benefits.

Mr. BURTON. Do you mean to tell me cadmium is as toxic a substance as mercury? Is that what you are saying? Come on.

Dr. FEIGAL. What I am trying to do is put it in the context of

how FDA regulates products. We do not assess the environment,

we do not assess the effect of pure compounds and absolute toxicity. We look at how they are used in practice.

Mr. BURTON. You do agree though that mercury vapors leech out

of the tooth?

Dr. FEIGAL. Yes, we do agree with that.

Mr. BURTON. And that it is ingested into the body?

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Dr. FEIGAL. Yes, we do agree.

Mr. BURTON. And it gets into the bloodstream?

Dr. FEIGAL. Yes.

Mr. BURTON. And it goes to the brain and other organs of the

body?

Dr. FEIGAL. Yes, we agree with that.

Mr. BURTON. And mercury has a cumulative effect in the brain?

Dr. FEIGAL. That is less certain, but there is literature on both

sides. It is the clinical impact though that is the standard for taking action on medical devices, not the toxicology, not the ability to

take preventive actions, but the actual observed effects.

Mr. BURTON. You know, I do not understand why—many people

in this country, probably the majority, do not know that there is

mercury in a silver filling in their mouth, in the amalgam. Why

doesn’t the FDA at least, since mercury vapors do escape into the

mouth and into the body, why doesn’t the FDA at least make people aware of that? Why not publicize that?

Dr. FEIGAL. The FDA’s authority on information about products

has to do with the labeling of products and only rarely does the

FDA actually directly intervene in the way that products are described or presented in informed consent. That is practice of medicine which the FDA is asked not to get involved in.

Mr. BURTON. What about the mercury in the vaccines, the thimerosal and that sort of thing?

Dr. FEIGAL. I am afraid I will have to get followup from someone

else in the agency who can comment about vaccines. That is outside my area.

Mr. BURTON. Thimerosal contains mercury that is injected into

kids, and you heard me talk about that earlier.

Dr. FEIGAL. Yes.

Mr. BURTON. I think that has been pretty well publicized, hasn’t

it? Hasn’t the FDA talked about that?

Dr. FEIGAL. Yes. But I think if you are talking about the informed consent process——

Mr. BURTON. I am not talking about informed consent. I am just

talking about making people aware.

Dr. FEIGAL. I think that is a reasonable request to do that.

Mr. BURTON. Then I would make that request, that the FDA put

a card or something in every dentist’s office saying that the amalgams that you get from your dentist contain approximately 50 percent mercury, and then let the people make the decision themselves. I think people ought to be held accountable for their actions,

but they at least ought to know what the hell they are doing. And

they do not.

Did you check that out? Ladies, did you check that out? What did

you find? Why don’t you sit down there at the table, Doctor, and

give us that. What was the amount?

Mr. RICHARDSON. They took a preformed pill-sized amalgam filling that I suspect was prepared in Dr. Haley’s lab, wiped it with

a napkin, and then held it to a Jerome mercury analyzer to measure the mercury content in micrograms per cubic meter. That device only measures the vapor. It does not measure particulate or

other forms.

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They took three measurements. The first one was 283

micrograms per cubic meter, which is over 10 times the threshold

limit value for occupational exposure and some I think about 100

times higher than the U.S. EPA reference concentration. The second measurement, when it was held slightly distant from the inlet

to the device, came back at 82 micrograms per cubic meter. Again,

that is approximately a little more than double the threshold limit

value. They then polished it again, held it to the front of the device,

and got a number of 774 micrograms per cubic meter. With 25

micrograms per cubic meter being the threshold limit value for occupational exposure, that is some 5 times higher than the TLV for

the air that passed over that pre-made amalgam filling.

Mr. BURTON. Doctor, come on up here. We will let you make a

comment on that. I do not want the American Dental Association

to feel left out.

You stick around up there. I want the FDA people to hear this

because that is why we asked them to be here is so they could

glean from the testimony some insights into what maybe ought to

be done.

Go ahead.

Dr. MACKERT. OK. This instrument that was used is designed for

measuring mercury vapor in a room where the collection volume,

which is, depending on the model, 250 milliliters to 500 milliliters,

the collection volume is small compared to the volume of air of the

room. Again, this is a matter that has been studied extensively in

the literature, particularly in Sweden by a colleague of mine named

Anders Berglund at the University of Umea. This is not an appropriate use of this instrument. I hope Dr. Richardson knows that

this is not an appropriate use of this instrument. To report

micrograms per cubic meter and then imply that a person inhaling

mercury vapor would be exposed to the levels that he described as

if that person were in a room with those concentrations, are you

saying that the person that would breath next to that would absorb

the same amount of mercury vapor as a person in a room with 280,

or whatever you just quoted, micrograms per cubic meter?

Mr. RICHARDSON. No. All I was trying to do was put into perspective the three measurements that were made by this device.

Agreed, in the context of if you were trying to estimate exposure,

you can in fact, and there have been studies done, use that information in combination with information on the size/shape of the

oral cavity, the amount of air that is inhaled with a breath, etc.,

to come up with estimates of exposure.

Mr. BURTON. Let me ask the people from the FDA something. I

asked the American Dental Association representative here who is

going to be on their decisionmaking board if they would agree to

do a study, take 100, 200, or 1,000 amalgams and split them up

and send them to different scientific research laboratories, like

Harvard or others, and have them tested under heat and abrasion

to measure the amount of mercury that is emitted from these.

Could the FDA participate or would they participate? It does not

sound like to me it would be that costly. You just make the amalgams and you send them and they would do the research. It does

not seem like it would take a rocket scientist to do that if you had

the proper equipment.

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Dr. FEIGAL. The FDA does relatively little funding of research

itself. It usually relies on the Public Health Service and on the

manufacturers or on other independent bodies to do the research,

or on standards bodies such as the International Standards Organization or ANSI to develop standards. We would welcome the results of such studies.

Mr. BURTON. Can you not admonish somebody to do that? You

guys, come on, you are the ones that put the pressure on supplements manufacturers and go in and raid them and everything else

to stop them from selling their supplements. You do all kinds of

stuff like that. Don’t tell me you do not have enough authority to

kind of push them along to make them do that. Why don’t you do

that?

Dr. FEIGAL. Well, believe it or not, Congress actually wrote some

authorities that we have to follow the rules. And in devices, the

logic would have to be that we would need that information in

order for the product to be used in a way that would result in it

being safe and effective. The way we have looked at the review of

the literature with the Public Health Service is we have made the

determination that the evidence to date still comes down in the

favor that these products are safe and effective.

Mr. BURTON. Dr. Tabak can do the study. He can do the study.

Dr. FEIGAL. Yes.

Mr. BURTON. He is a scientist who works in that area. But you

guys say because it does not come down on the side that you agree

with that no further studies are necessary.

Dr. FEIGAL. No I did not say that.

Mr. BURTON. That is what I got from it.

Dr. FEIGAL. No. I apologize if I gave you that impression. We

welcome ongoing developments in the science. We can measure

mercury exposure levels, as you have heard, that we were never

able to measure in the past. And when we look at that information

and we say as a biomaterial is this still an acceptable biomaterial,

then we look at that both with animal studies and with human

studies and benchwork.

Mr. BURTON. Have you done the kind of study I was just talking

about?

Dr. FEIGAL. As I understand it, you were asking to see what the

kind of exposure would be. But the context that we are asked to

regulate devices in, the context of risk and benefit, and so we have

to look at the two as they weigh together. We would have to conclude in order to take an action that the action was necessary for

the product to be used safely and effectively.

Mr. BURTON. So what kind of a scientific research project would

you have to have that would give you that kind of information?

Dr. FEIGAL. I think there are many different sources. I think the

ongoing development of the toxicology. Many of the questions today

where there were disagreements of conflicting studies, it would be

nice to get the animal work and the benchwork about what is the

level of exposure, the duration of exposure. You heard that there

was disagreement about the half-life of materials in different parts

of the body and what the consequences of those are. We use the

information from epidemiology, we use the information from studies such as the studies that Dr. Tabak described. It is a process

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that is ongoing with us. So that when we feel that a risk has

reached a level where changing the classification or changing the

requirements by a manufacturer would make the product be used

more safely or more effectively, then we take those actions. So we

are constantly in the midst of that process. We just do not fund it

ourselves; we look at what everybody else does.

Mr. BURTON. But you could, of course, urge this kind of a study

be done.

Dr. FEIGAL. Yes, we could, and we would probably do that in the

context of the Public Health Service, particularly given the number

of particularly small device firms.

Mr. BURTON. Would you be willing to urge that amalgams in

some quantity be tested by leading scientific laboratories to find

out the amount of emissions?

Dr. FEIGAL. Yes, I would be willing to do that.

Mr. BURTON. Would you do that. OK. Very good. We finally got

to where I wanted to go. [Laughter.]

Ben, do you have a question?

Mr. GILMAN. Thank you, Mr. Chairman. Dr. Feigal, elsewhere in

the FDA mercury is not generally recognized to be safe, but apparently the dental device division classifies dental mercury as a Class

I safe and effective device. Is that correct?

Dr. FEIGAL. That is correct.

Mr. GILMAN. Why? Is that classification likely to stand, or is it

under review?

Dr. FEIGAL. We have proposed reclassifying it as a Class II device. Again, the context of the risk is risk to the patient in its use

as a medical device. So it is not the same as risk from food or risk

from an environmental exposure.

Mr. GILMAN. What are the differences in Class I, II, and III dental devices? What are the differences?

Dr. FEIGAL. Class I devices are devices which require general

controls for medical devices, including registering and listing the

product, having a quality manufacturing system which includes a

mechanism of detecting adverse experiences in a reporting system

and reporting them to us, it includes labeling requirements and

other things, but it does not require that the product be submitted

to FDA for review prior to marketing. There are a small number

of Class Is but most of them are exempt from pre-marketing.

Mr. GILMAN. What about Class II?

Dr. FEIGAL. Class II, there are about 800 different Class II products. Each of those has its own set of special controls. The special

controls are the controls that are necessary for the product to be

used safely, in addition to the controls the Class Is have. So, for

example, in the case of the alloy, there is a range of materials that

are allowed in alloys, a range of amounts that have been developed

by the American National Standards Institute and by the International Standards Organizations.

Mr. GILMAN. And what about Class III?

Dr. FEIGAL. Class III is a group of products that must demonstrate that they are safe and effective, and they usually are products that have no comparable product that is on the market or a

product in which there is a substantial risk and the only way to

demonstrate the safety and the effectiveness of the products is by

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performing clinical trials, usually prior to marketing, although

when a product is on the market at the time of the amendments,

they do not come off the market if they are classified as Class III.

Mr. GILMAN. So an amalgam with mercury in it is no problem

and that is why it is a Class I?

Dr. FEIGAL. No problem is—the Class I is the appropriate level

of regulation to have a well-manufactured product that performs as

intended and can be expected to be substantially equivalent in safe

and effective compared to other products.

Mr. GILMAN. Do you have any reservations about the safety and

effectiveness in mercury being used as part of amalgam?

Dr. FEIGAL. The misconception I think about safety in FDA is

that we certify products as safe. We do not. All products have risks.

The question is is the risk——

Mr. GILMAN. Does mercury have a risk?

Dr. FEIGAL. Of course it does.

Mr. GILMAN. Then why is it a Class I?

Dr. FEIGAL. It is Class I for the same reason that medical needles

in shops are Class I, is it can be manufactured in a way that it

will perform in the way that it is expected and will be safe and effective as its intended use. Just as some forms of mercury are medical waste, used syringes are medical waste.

Mr. GILMAN. Tell me, I understand that the waste product, the

removal product is classified as a hazardous substance. Is that correct?

Dr. FEIGAL. That is nothing that FDA has anything to do with.

It does not affect our risk classification at all.

Mr. GILMAN. But it has been classified that way by EPA; is that

right?

Dr. FEIGAL. The vast majority of medical devices after they have

had human contact are classified as hazardous materials and must

be handled properly, according to the EPA.

Mr. GILMAN. If it is a hazardous material, why isn’t it reclassified as a hazardous material for the dental community?

Dr. FEIGAL. The EPA classification is different than the FDA

classification. The FDA risk is risk to the patient as a medical device. There are OSHA classifications on risks to health personnel,

there are EPA classifications on risk to the environment. So there

are things where a product will be in one classification but not in

another.

Mr. GILMAN. So it can be a risk to the environment but not to

the patient, is that what you are saying?

Dr. FEIGAL. Absolutely. The vast majority of medical devices

waste are hazardous to the environment and must be properly handled and incinerated.

Mr. GILMAN. Doesn’t that seem to be inconsistent in your mind,

that it is hazardous to the environment but not to the patient?

Dr. FEIGAL. No, because it is in the context of use. A needle is

hazardous to the environment but it is not hazardous to the patient. It is effective for what it is intended to do.

Mr. BURTON. Would you yield for just 1 second.

Mr. GILMAN. I am pleased to yield to the gentleman.

Mr. BURTON. You heard the dentists talk earlier at the first

panel and they said mercury in the amalgam is toxic before, and

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it is toxic after you take it out, so why isn’t it toxic or a problem

when it is in the tooth?

Dr. FEIGAL. My understanding of that discussion was that the

toxicity was in terms of how EPA considered it in terms of toxicity

to the environment. That is a different issue than its risk to the

patient as a medical device.

Mr. BURTON. If the gentleman would yield further. That substance that is taken out of the tooth, that amalgam goes into the

water supply, into the sewage system, into everything. And we

know from you that we should not eat a lot of fish that contain

mercury. Where do you think that mercury comes from? It does not

come out of the air.

Dr. FEIGAL. The environmental issues are not the basis of the

FDA risk classification.

Mr. BURTON. Do you guys ever talk to one another? I do not understand it. If mercury is a toxic substance—Ben, thank you for

yielding—if mercury is a toxic substance, it is toxic before it is put

in the mouth and it is toxic afterwards, you would assume that

there is a modicum of risk while it is in the mouth. You had the

environmentalist there a while ago talking about the horrible problem they are having with wastewater treatment plants around the

country and the water system, and they are dumping huge

amounts of these amalgams down the drain because there is no

regulation by FDA on what to do with it. Why don’t you regulate

what to do with those things after the dentist takes them out of

the mouth so they do not get into the ecological system?

Dr. FEIGAL. Because Congress has not given us the jurisdiction

to do that and they have given the jurisdiction to the EPA and to

OSHA. Another common example, for example, is the use of radioactive substances in medical devices. Those are hazardous products

to the medical environment; they must be handled in specific ways

before use, they must be disposed of carefully after use. But our

risk classification would be to classify their risk based on their use

as a medical device. OSHA, EPA, the State authorities would take

care of the other things. These have been divided.

Mr. BURTON. Let me just make one more comment and then I

will yield back to my colleague. You know, because of the threat

to the security of America, we are combining a whole bunch of

agencies into what they call Homeland Security. It sounds to me

like we ought to do that with the health agencies. We ought to take

EPA and the health agencies and everybody else and put them

under one governing body so that you guys work together.

If there is an amalgam that is dangerous before and dangerous

afterwards to the environment, and I believe it is dangerous to the

person, it seems to me there would be a consistency of thought.

And it does not sound like there is. You guys are saying the amalgam is not a threat to the person, at least not in your opinion right

now, the merits outweigh the problems with it, and yet before and

after it is a problem for the ecology and the environment. There is

an inconsistency there that just alludes me.

Dr. FEIGAL. There are countries, Singapore is an example, where

the EPA and the FDA functions are in the same organization. But

that is not how we have been organized. Historically, actually

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dent Nixon created the EPA. The functions were separated and

made different.

Mr. BURTON. Ben.

Mr. GILMAN. Thank you, Mr. Chairman. Dr. Feigal, how do you

explain the extraordinary variance between the amalgam’s vapor

release rates between the various researchers, as illustrated by Dr.

Haley, Richardson, and Fischer?

Dr. FEIGAL. Again, we do not dispute the fact that there is exposure to mercury. The question is whether or not mercury as a medical device still has benefits that outweigh the risk and whether or

not the product meets the standards that we look at for a biomaterial in terms of its toxicity.

Mr. GILMAN. What are the benefits of mercury usage?

Dr. FEIGAL. The benefits of dental amalgam would be a question

better answered by Dr. Tabak or one of the dentists. But the question is it effective as a dental restorative device, I think that probably has not been one of the things that has been questioned.

Mr. GILMAN. Based on today’s standards at the FDA, if mercury

amalgams were new and were submitted for approval as a dental

device using the existing published research, would it be approved?

Dr. FEIGAL. That is a very good question. I have actually thought

a lot about that.

Mr. GILMAN. I am pleased to hear that.

Dr. FEIGAL. The products that are already on the market, the

burden of proof is on the agency to demonstrate that the risks are

high enough to take them off the market. And the standard is so

high that in 27 years only one product has been banned and no

product has been involuntarily withdrawn from the market because

of safety concerns by FDA because of the very high standards for

demonstrating the evidence that has been placed on the agency

through the Food, Drug, and Cosmetic Act and the device amendments. It is not our choice, it is the way that it was set forward.

Now a new product coming onto the market would actually have

to show as safe and effective before it was on the market. And if

we start by saying we assume that its properties as a restorative

material would be relatively easy to demonstrate, so it would meet

the effectiveness standard relatively easily. So the question is if it

were a new substance, what would they have to do to show it was

safe. And there they would have to meet recognized international

scientific standards on the toxicology of the substance, to show

that, in fact, the way it was used that the toxicity was not a problem. It would not be an issue of whether there was toxicity or not,

it is whether or not in the context of the use you could actually

demonstrate risk. The kinds of studies that Dr. Tabak has done

would be the kinds of studies that would be looked at, where you

would have a very careful look at a group that was exposed and

not exposed to look for clinical effects. We would also rely on animal work and on what is known about the physical properties of

the materials.

But that is one of the differences. The old products, the assumption made in the device amendments was the old products were

safe and new products to come onto the market only had to be

shown to be substantially equivalent to a product on the market in

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ucts newly coming onto the market, products must show that they

are safe and effective.

Mr. GILMAN. Dr. Feigal, if you were to deny the use of mercury

in an amalgam for dentists, what harm would that do to the practice of medicine?

Dr. FEIGAL. We would have to actually do that based on the legal

tools given to us in the statute, and the statute requires a very

high demonstration of harm, not to answer the question of whether

it would be a reasonable precaution. The statute would require that

to ban a product we would actually have to show the damage that

the product was causing in use as a medical device.

Mr. GILMAN. Do you have any evidence to either support or refute Dr. Haley’s statement that, ‘‘The data regarding the specific

ability of mercury to cause much of the aberrant biochemistry

found in the brain and to produce many of the widely accepted diagnostic hallmarks of Alzheimer’s disease is unquestionable.’’ He

said it is unquestionable. How do you respond to that?

Dr. FEIGAL. I think part of the discussion that occurred during

the first panel was whether or not that was a view that was widely

accepted. We looked at the balance of evidence across different scientific experts and studies and we would have to consider that an

interesting hypothesis but something which is unproven. There are

also concerns about the issue of aluminum in Alzheimer’s disease

and other types of exposures, and we need to look at all of those

types of issues. But I do not think there is a scientific consensus

that agrees with Dr. Haley at this point in time, would be my assessment.

Mr. GILMAN. So you disagree with Dr. Haley’s findings?

Dr. FEIGAL. Looking at it in the balance of the rest of the data

and research on Alzheimer’s disease, I can speak for the process of

looking at this, but we would probably not agree with him at this

time.

Mr. GILMAN. Again, with regard to the use of mercury, in your

testimony you state that amalgam as a restorative is used to treat

dental caries. Is that correct?

Dr. FEIGAL. That is correct.

Mr. GILMAN. But that actually is not true, is it? You are not

treating a cavity. The dentist drills out the cavity and fills in the

gap with the amalgam. You do not actually treat it or cure it. You

clear it out and fill in the gap. So what would be the harm in filling

in the gap without mercury?

Dr. FEIGAL. There are multiple products that can be used the

way that amalgam is used, and the way you describe it is a correct

characterization of how it is used. The FDA standard, the standard

that is in the Act for products to be on the market is not that they

should be removed from the market if there is a better alternative.

The standard is that they are safe and effective for use.

Mr. GILMAN. Are there better alternatives?

Dr. FEIGAL. There are alternatives with other advantages and

disadvantages.

Mr. GILMAN. Are there better alternatives than using mercury in

the amalgam?

Dr. FEIGAL. Perhaps you should ask Dr. Tabak.

Mr. GILMAN. Dr. Tabak.

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Mr. TABAK. There are alternatives, sir, but not substitutes.

Mr. GILMAN. The question is, are there better alternatives than

using mercury in amalgams?

Mr. TABAK. Currently, in some clinical conditions, no.

Mr. GILMAN. And what are those conditions?

Mr. TABAK. If you have extensive damage to the tooth, there are

situations where you cannot restore it with a material such as a

composite restoration, which is most often referred to as the alternative restorative material.

Mr. GILMAN. And you say there are no materials that could be

utilized except a mercury amalgam?

Mr. TABAK. As was indicated in the first panel, sir, you can use

a gold restoration which carries with it a very high cost.

Mr. GILMAN. But it is available?

Mr. TABAK. It is available.

Mr. GILMAN. And it is a better usage than a mercury amalgam,

is that correct?

Mr. TABAK. I would not say it is better, sir. I would say that it

is an alternative.

Mr. GILMAN. Is it a preferable alternative?

Mr. TABAK. I would not say it is preferable, sir. I would say it

is an alternative.

Mr. GILMAN. Thank you. Thank you, Mr. Chairman.

Mr. BURTON. Chairman Gilman asked one question, Dr. Feigal,

that you kind of skirted around. I want to get a more definitive answer. Based on today’s standards at the FDA, if mercury amalgams

were new and were submitted for approval as a dental device,

using the existing published research today, would you approve it?

Dr. FEIGAL. I think we would approve it as a restorative, yes I

do.

Mr. BURTON. Do you. And what class of device would you call it?

Dr. FEIGAL. It would still probably be a Class II device because

most of the evidence would not have to come from clinical evidence.

Mr. BURTON. Now after you do that study I asked you about a

while ago, if it shows that there is an inordinate amount of vapor

leeching into the body, would you maybe reconsider?

Dr. FEIGAL. What we would have to know is what the significance was of the release of the vapor. And it comes back to the

point I must not have made very clearly before, which is it is not

the exposure which is at issue, it is the clinical significance of the

exposure. That is what needs to be established.

Mr. BURTON. Man, I do not want to breath mercury vapors. Do

you? Do you like breathing mercury vapors?

Dr. FEIGAL. I would prefer not to.

Mr. BURTON. But you put them in your mouth. And if you have

an inordinate amount of mercury vapor leeching out because you

brush your teeth, because you eat something, because you drink

hot coffee, would that not be of concern, especially when you know

it has a cumulative effect in the brain? Do you mean that does not

even concern you? You are a scientist, a doctor.

Dr. FEIGAL. It is also of concern to me not to be exposed to xrays, and yet I still——

Mr. BURTON. I am not talking about x-rays.

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Dr. FEIGAL. But I still watch my television set. If we were to say

why take the risk——

Mr. BURTON. But you sit further back, you do not sit right up on

top of it.

Dr. FEIGAL. There is still exposure. Why should I have any exposure?

Mr. BURTON. I am talking about mercury. I am not talking about

your television set.

Dr. FEIGAL. The issue is the same. We have to know at what

level the exposure actually has clinical significance.

Mr. BURTON. That is what I am asking about in this study. If

you find that there is an inordinate amount of exposure from the

emission, do you think you might reevaluate that?

Dr. FEIGAL. If the exposure was known to be clinically significant, then we would change, yes.

Mr. BURTON. I hope you will allow our colleague that has done

extensive research on this to be part of that research project that

you are going to recommend.

Dr. FEIGAL. We are always happy to look at all sources of evidence.

Mr. BURTON. I am going to send you a letter after the hearing

that says you said you thought you could do this and I am going

to suggest that you have him as part of the research project. I

would be very happy to take a look at the results next year because

I am probably going to be very active in this next year as well and

maybe we can talk again.

Dr. MACKERT. Mr. Chairman, I wonder if I could——

Mr. BURTON. Did you have a question? Yes, please.

Dr. MACKERT. I wonder if I could make a comment on your question about the release of materials into the body from amalgam and

other materials.

Mr. BURTON. Yes.

Dr. MACKERT. I have studied dental materials for 24 or 25 years,

all different materials. I work in ceramics, every material that we

use in the body releases elements into the body and those are absorbed into our body. And if we look, there is gold in the tissue

under my ring here. That is on the same order of magnitude as the

mercury that would be in my gum tissue next to my filling.

Mr. BURTON. Toxicity?

Dr. MACKERT. Gold is a very toxic element.

Mr. BURTON. It is as toxic as mercury?

Dr. MACKERT. If the dose is the same, the toxicity is similar.

Mr. BURTON. So if I have a gold cap on my tooth and I have a

mercury filling, they are both the same?

Dr. MACKERT. In terms of the effect on you? Both of them have

no effect on you. But let me just ask a question of you, if I may.

Mr. BURTON. Oh, sure. If I do not know, I will just tell you.

Dr. MACKERT. I do not know what materials you had your amalgams replaced with.

Mr. BURTON. A composite. My dentist is right there.

Dr. MACKERT. Did the dentist tell you the ingredients of that

composite before you put it in your mouth?

Mr. BURTON. Sure, he told me.

Dr. MACKERT. What were the ingredients?

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Mr. BURTON. I do not remember. Tell him.

Dr. MACKERT. Did he tell you about the allergenicity of the hydroxy ethyl-methacrylate that is used as a bonding agent? It is one

of the most potent allergens used in dentistry. Bob Erickson, who

is the pride——

Mr. BURTON. And it is as toxic as mercury?

Dr. MACKERT. It is an allergin. It causes an adverse health effect.

What I am saying is that if we remove materials just because they

have the potential of causing adverse health effects in certain small

groups of people, we will not have anything. I had a patient call

me 2 weeks ago who was distressed because she wanted to have

her amalgams replaced and she wanted to know even a temporary

material that she could put in until she could make a decision. I

told her some of the options, and she’s, well, no, that has zinc in

it, that has this in it. She was concerned about everything. And

this is what I am concerned about as a dentist is that people become so frightened because of alarmist predictions that they cannot

make a decision about——

Mr. BURTON. I have allowed you a lot of latitude because you do

represent the ADA.

Dr. MACKERT. Thank you.

Mr. BURTON. So I am going to allow our people who have a contrary point to view to respond. Go ahead.

Mr. RICHARDSON. I would agree that risk assessments of dental

materials are sorely needed. When I completed my work on dental

amalgam, the question was raised, well, we know more about amalgam now than anything else, if we ban it do we jump out of the

frying pan into the fire? And I looked around and there was not

a single thing written in the published record on the risks of any

other materials.

I approached the CDA. They refused to fund any work on risk

assessment. I approached Health Canada and they refused to fund

any work on risk assessment. The IAOMT funded my work to assess the risks posed by composite resin materials following the

exact same procedures used that I applied to dental amalgam. The

exposures to the components of composite resins that occur from

having 25 fillings of composite resin material are hundreds to thousands of times below the U.S. EPA safe or reference doses for those

materials.

I submitted that work to a dental journal for publication because

it seemed to me that it would be in the interest of the dental community to know it, and, yes, it was rejected out of hand because

the name Mark Richardson was attached to it. It was gobbled up

by a peer reviewed journal that is dedicated to human and ecological risk assessment, a journal that is published here in the United

States.

It is unfortunate that there are still no risk assessments going

on on any other materials. There has not been one published on

gallium, which was investigated as a possible replacement for

amalgam, there has never been a risk assessment done on gold,

and, in fact, gold is one of the most safe metals that you can be

exposed to. Where this information comes from, I would love to see

the literature, the risk assessments that appear to have been done

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on these materials because they are not published anywhere. That

is all I have to say.

Mr. BURTON. Just 1 second. Why has there not been risk assessments done on all these materials?

Dr. FEIGAL. There are actually assessments done on the materials, the Bead National Toxicology Standards. These are set by the

International Standards Organization on Toxicology. Much of the

material in manufacturing is proprietary information. It is——

Mr. BURTON. You guys are supposed to make sure that the

things they put into our bodies are safe. And you are now telling

me that it is proprietary, so you do not know?

Dr. FEIGAL. We review it. The fact that certain material is not

released is, again, a creation of Congress.

Mr. BURTON. Well if you are comparing it, if you are finding out

if there is a toxic substance in there, shouldn’t that be made known

to the public? Proprietary interests should not take precedence over

what the public should know.

Dr. FEIGAL. We release the information which legally is not a

trade secret. That is all defined by law and by statute. We release

that information. It is our responsibility to review the information,

and if there is not adequate information, to not release the product.

Now one of the concerns that is raised is not so much on the

short acute exposure but on the long-term exposure. There is no

way to actually cut short the fact that if you have got a material

that has been used for 5 years, you do not know the 10-year or the

thirty year effect. And that is something that we have to live with

all the time with new materials. There is no way to test something

for 30 years before you use a new material.

So we look at the acute effects, we look at exaggerated dosing.

Most of the material done on alloys, on materials have intellectual

property protections, have trade protections provided by Congress

that does not protect them from showing it to us but does create

the kinds of frustrations that exist in the community of saying we

do not know much about these.

Mr. BURTON. There needs to be a modicum of trust between the

Federal Government and the people. And if there are questions

about whether or not something might or might not be harmful to

an individual, proprietary rights, there has got to be some way

around that. He said that these things have not been categorized

or checked and you are saying, well, we look at them.

Dr. FEIGAL. We do, and we actually——

Mr. BURTON. I know, you say we look at them, but because of

proprietary interest we cannot let the public know about them. You

know, the problem is the trust factor. People want to know that

they can trust their government. And when some things that happen in the health agencies that shows that there is a problem, they

want to know, especially things they are putting into their body.

Dr. FEIGAL. That is right. I would agree with that. And I would

say that the responsibility you have given us is to keep those

things from being used. And one of the things that is written in

the statute that could be changed, it is in the current statute, is

that when we turn a company down for a request to use a certain

material, that information cannot be released. It cannot be released

even that they have requested it or the basis for our turning it

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down. So there are certain things that are built into the current

framework that I think could be addressed and say is this the way

we want to do business at this point.

Mr. BURTON. If you have recommendations on things that should

be changed so that the public can be better informed, let me know

and I will help carry the mail for you.

Mr. Gilman.

Mr. GILMAN. Thank you, Mr. Chairman. I want to be clear on

something you have said. You have tested these amalgams. You

have made up a list of those that are bad and those that are good

apparently. Is that correct?

Dr. FEIGAL. We actually do no testing ourselves at FDA, or a relatively small amount because we have a very small laboratory.

Mr. GILMAN. Who does the testing?

Dr. FEIGAL. All the testing is done by manufacturers and they do

it in accordance with international standards that are set by international standards bodies. So in this case, the standards for alloys

are set by the American National Standards Institute and by the

International Standards Organization, ISO.

Mr. GILMAN. So there is no testing by any public agency?

Dr. FEIGAL. No, there is not, nor is there of drugs, nor is there

of foods that come to market. That is not the standard. There are

500,000 different devices on the market in the United States. We

approve 40 to 50 devices a day in this country.

Mr. GILMAN. What do you base your approval on?

Dr. FEIGAL. We base it on having a risk-based approach, so that

the highest risk products must show safety and effectiveness with

clinical trials, the medium risk——

Mr. GILMAN. But how do you know the safety and effectiveness

if you are not doing the testing? Are you relying on the manufacturer?

Dr. FEIGAL. For drugs, for devices, and for biologics, we rely on

the manufacturer’s testing. We inspect. We have severe punishment and penalties for companies that falsify information and do

not release everything to us.

Mr. GILMAN. How do you know whether it is an accurate assessment if you are not testing it?

Dr. FEIGAL. We do not retest. We do not have the tens or hundreds of billions of dollars that are spent every year by the device

community testing their devices. We set the standards by which

they test the medium and high risk devices, they present that data

to us and we inspect the data and we inspect their facilities.

Mr. GILMAN. That is like leaving the fox in the chicken coop to

do the policing.

Dr. FEIGAL. It would be if we allowed them to self-certify. But because we review their raw data, which no other country in the

world does, we are the only country that goes in and inspects the

raw data, it——

Mr. GILMAN. Let me ask you, Doctor. Don’t you think it would

be more important for the association, your agency to do the testing

rather than to allow that testing to be done by the manufacturer?

Dr. FEIGAL. We would then need to have a testing facility of the

same magnitude of the testing facilities of the manufacturers in aggregate. They currently spend billions of dollars doing this.

141

Mr. GILMAN. I am asking, do you think it would be more important for the agency to do the testing rather than the manufacturers?

Dr. FEIGAL. Quite frankly, I do not think the Government could

do it as quickly as the private sector.

Mr. GILMAN. I am not talking about the expedited testing. I am

talking about the importance of the agency to do the testing.

Dr. FEIGAL. In terms of doing all testing, no. We have to be able

to inspect what the manufacturers are doing as they manufacture.

It is not just even the issue of meeting the standards at the time

of approval, it is also the standards when they are manufacturing.

So if the logic was that we would have to do all of the testing, we

would also have to do all of the testing of their ongoing manufacturing.

Mr. GILMAN. Would that not be more beneficial to the public?

Dr. FEIGAL. Only if we had the resources that industry has. And

I testified——

Mr. GILMAN. If you had the resources, would that be more beneficial to the public for your agency to do the testing?

Dr. FEIGAL. I would seriously doubt if a single agency based in

one location, funded on an annual basis in the way that Government manages to run itself could actually compete with the private

sector in terms of producing quality products.

Mr. BURTON. There are advisory panels over at the FDA and the

health agencies who are supposed to do what we call double blind

studies and check all that stuff out before you put it into the marketplace.

Dr. FEIGAL. The advisory panels review the evidence as well. But

the thing which is unique about both our relationship and the advisory panels in the world is our ability to request all the data and

the raw data, and that is what gives us the ability to make sure

that the studies are done properly.

Mr. BURTON. Ms. Watson.

Ms. WATSON. Thank you, Mr. Chairman. I must apologize for not

being here throughout the hearing. If I become redundant, would

you please let me know.

I am sorry that Dr. Mackert left the room. I wanted to be sure

I heard him correctly. And so I am going to try to restate what he

said and maybe you two gentlemen can confirm. I think I heard

him say that there is no risk to mercury in the dental amalgam.

Is that what he said?

Mr. TABAK. I cannot speak for him. I do not know.

Ms. WATSON. Did you hear him?

Mr. TABAK. I think that is what he said, yes, Ms. Watson.

Ms. WATSON. OK. Would you two gentlemen confirm that?

Mr. TABAK. There is no scientific evidence to indicate that there

is a risk.

Ms. WATSON. Is that your response to his statement?

Mr. TABAK. Yes, it is. That is correct.

Ms. WATSON. OK. The word ‘‘amalgam’’ itself is part of the meaning of the word ‘‘amalgam with mercury,’’ yes or no?

Mr. TABAK. Indeed it is.

Ms. WATSON. Is mercury toxic?

Mr. TABAK. Elemental mercury is toxic.

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Ms. WATSON. Is mercury toxic?

Mr. TABAK. Elemental mercury is toxic.

Ms. WATSON. Would you answer my question. Is mercury toxic?

Mr. TABAK. I am trying to give you a correct answer.

Ms. WATSON. Is it yes, no.

Mr. TABAK. Yes.

Ms. WATSON. Thank you. Now is silver mercury? Does it contain

mercury? Yes or no. Silver amalgam fillings, does it contain mercury?

Mr. TABAK. It does.

Ms. WATSON. Yes. Almost up to 50 percent?

Mr. TABAK. Yes.

Ms. WATSON. OK. Now you scientific people are doctors. I think,

Dr. Feigal, you are an M.D.?

Dr. FEIGAL. Yes.

Ms. WATSON. To do no harm, what would you have against advising dentists to advise their patients that an amalgam with mercury

is what we call silver, it is an amalgam, it is not pure silver, what

would you have against it?

Dr. FEIGAL. No problem at all.

Ms. WATSON. All right. Would you advise that we then say to

dentists you should inform your patients?

Dr. FEIGAL. Yes.

Ms. WATSON. OK. Now we all agree that mercury is a toxic substance. Would both of you agree?

Mr. TABAK. It depends on the level of exposure.

Ms. WATSON. Let me repeat. Regardless of the level, poison is

poison.

Dr. FEIGAL. That is not true. Digitalis is an effective drug on one

level and a poison on another.

Ms. WATSON. Hold on, sir. Mercury is a toxic substance. Agreed?

Dr. FEIGAL. Not in all uses, not in all settings.

Ms. WATSON. OK. I want what you just said given to me. So whoever is recording this, I want to be sure I can quote you correctly.

Now would you agree that once you have a silver filling, mercury

amalgam filling, that it emits a vapor as long as it is within your

mouth. Is that a true statement?

Dr. FEIGAL. Yes.

Mr. TABAK. Yes.

Ms. WATSON. All right. If we know that, why is it a medically

trained person, a dentist would not want to share that with the patient. Doesn’t the patient have a right to know. I, as a legislator,

and my colleagues are here to protect the public and we speak for

the public. Why is it that the ADA will not tell the public that mercury amalgam is harmful but they can choose to have it in their

fillings. Now can you explain that to me?

Dr. FEIGAL. Well, you started by saying should patients be told

that the product contains mercury, and should we admit that we

know there is exposure from vapor release. I think those are appropriate things to discuss. And I think patients should be informed

that the evidence on the health risk is something that is actively

being studied as we speak, even in studies by the National Institutes of Health. Where it gets more difficult is asking a patient to

understand what does it mean to have a small amount of mercury

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release, just as it is hard for them to understand what their risk

is from other low level exposures.

So I think we need to actually think about the message that we

are trying to get. I think the patient should be informed. But it is

similar to the question about the composites and about the effect

of what is the long-term effect of having a substance like methylmethacrylate in your mouth and what is known about that. I think

there does need to be a much more informed and empowered consumer and they need to be able to make the choice.

I suspect where there is a difference in where we may being

agree to disagree——

Ms. WATSON. Would you yield for a minute?

Dr. FEIGAL. Sure.

Ms. WATSON. That is exactly what this bill is trying to do. We

would like you, as representatives of the dental profession or researchers, or whatever, to educate. I asked in my bill of 10 years

ago in the State of California for a protocol. We never got it because the panel was controlled by dentists. I was told by the dentists that they did not want to scare off their patients, and that it

was cheaper to use a mercury amalgam or a dental amalgam, or

silver, whatever they want to call it, than the alternative. So because it was cheaper, they did not want to inform their patients.

I was appalled at that response coming from a medical professional. I am appalled with what I have heard here this afternoon.

You do not want to answer my questions directly. Why do you

think a patient would not listen to the doctor if a doctor had a protocol which explained what was in that silver. Why are we continuing to delude people by saying you have a silver filling in your

mouth when we know we are not telling them the truth.

We had to research paint because we found that babies were

chewing on the railings of their bassinets and it was very poisonous

to their system. We did long-range studies, long-term studies and

found out that those children were having difficulty in schools

when they got to school. Asbestos, which was a certified building

material, we found out it was a carcinogen, long-term studies. Why

could we not do long-term studies on mercury at any trace amount,

trace, I say, amount. And you just agreed that over a period of time

it does seep out and has a vapor. Why would we want to delude

people by not telling them. So that is what the bill does.

The other thing that I am appalled at is that you would not say

we need to do the studies, we need to look at the risk, because we

think that if mercury is going to be taken out of thermometers, if

mercury is going to taken out of other products, that it is still all

right to use it in someone’s mouth. I do not understand your——

Dr. FEIGAL. The question to me was should FDA do the studies,

and FDA does not do studies except for very small parts. We welcome the studies that are done, we encourage them, and we review

the results.

Mr. BURTON. If the gentlelady would yield just a second. Dr.

Feigal very graciously agreed earlier that he would—I think I am

quoting you correctly—that you would——

Dr. FEIGAL. Urge.

Mr. BURTON. Urge. I urged you and you said you would accept

the urging, or words to that effect. But he would urge some of the

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outside scientific research facilities to take amalgams, maybe 100,

200, or 300, and have them checked to find out the amount of emissions of mercury vapor that is coming out over a period of time. I

also urged that Dr. Haley be a part of that study because he has

some expertise in the area.

Ms. WATSON. Great.

Mr. BURTON. So they have, in essence, agreed that they would

work with us on that.

Ms. WATSON. Thank you. I do not want to be redundant. Let me

just ask one more question. I understand that the manufacturers

of products do the research, and I understand that you said you do

not have the capacity comparably to do the research. Can someone

respond to why the FDA has not required the manufacturers to

show the health effects of what you have agreed to is the mercury

vapors. Can someone respond?

Dr. FEIGAL. These were products that were on the market in

1976 when the Device Amendments were passed. And for FDA to

take an action about safety, actually the burden falls to the Government, not to the manufacturer, to present the evidence that a

product needs to be up-classified or an adverse action taken against

it. And so this is an area where, because this is a product that was

on the market, the burden of proof is on us.

Now the way we approach that is not do the studies ourselves

but to review the scientific literature, most of which in this area,

quite frankly, is not done by the manufacturers. One of the things

to remember about the device industry is that of the 12,000 firms,

half of them have five or fewer employees; 92 percent of them qualify or meet the Commerce Department’s definition of a small business. And as Congress looked at how do you regulate an industry

that makes so many products and makes 500,000 different products, they gave us the responsibility of doing it in a risk-based

fashion, starting with the assumption that most of the things on

the market were on the market because they were proven products.

And there are products which have been up-classified and which

we have called for the highest levels of evidence for. But as we

have gone through the process of reviewing the literature, it has

been very difficult for us to say we think mercury is causing Alzheimer’s disease, or we think the evidence shows that mercury is

causing the other kinds of things.

Ms. WATSON. Would you yield, please?

Dr. FEIGAL. Sure.

Ms. WATSON. I am not trying to tell you what the outcomes

would be of your studies. But I am just wondering why you have

not done them in the past. And I surely would have thought you

would consult with Dr. Richardson. I just heard him here for a

minute and he has done some of this risk assessment and he says

that his results were not even considered. And so it seems as if

there has been research and studies done, but apparently not at

the scholarly or empirical level that FDA would want to be concerned with. I have difficulty understanding why the FDA has

never classified mercury fillings.

That is the reason why this bill is here, do you understand that,

because we had dentists dragging their feet, and they finally told

me why. So we just got rid of the panel and we put people on there

145

that are really concerned about the public’s health. And by your

own admission, vapors are emitted as long as there is mercury in

the amalgam. I think that would be enough to tip you off that you

ought to classify, you ought to do the research, you ought to do it

yourselves.

Therefore, we are going to help you out. We have a bill here, and

I am thinking about amending it, Mr. Chair, to put in a required

study and maybe some dollars to back it up. So as this bill moves,

we are going to look at an amendment. So we are going to do your

work for you. We are going to direct you. Because our first and

foremost interest is protecting the health of the public. And if one

person is injured by something they thought was silver and the

dentist did not say it was mercury but silver, then you are deluding

the public and we are not going to stand for that. So this bill is

here because we are interested in the health of every single American.

I want to thank you, Mr. Chairman, for holding these hearings.

I will turn it back to you.

Mr. BURTON. Thank you, Ms. Watson.

Mr. Gilman, do you have any more questions?

Mr. GILMAN. No questions.

Mr. BURTON. I know you have been here for a long time. I want

to thank you very much for your patience, all of you in the first

panel and the second panel. I am going to see you again to make

sure I get the rest of the amalgams out of my mouth.

I want to thank John Rowe and Beth Clay for their hard work

on the hearing.

With that, we stand adjourned.

[Whereupon, at 2:43 p.m., the committee was adjourned, to reconvene at the call of the Chair.]

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