For more than a year, Springfield radiologist David Ayoub
has immersed himself in the noisy politics of a silent
disease. He’s familiar with the characteristic blank stares
of autistic toddlers and the quiet panic of parents
wandering uncharted medical, financial, and emotional
He’s equally familiar with the quiet panic of
pharmaceutical giants who can read the writing on the wall.
The big drug companies, according to recent reports, may
have known for years of the potential risks of thimerosal, a
mercury-based preservative used in many common vaccines.
Mercury exposure has been linked in several studies to
neurodevelopmental disorders that afflict children,
including autism and attention-deficit/hyperactivity
Ayoub has plunged into the scientific literature — and
emerged fully convinced that the case against the
preservative is “unequivocal.” He’s helping lead the push in
Illinois to ban mercury from vaccines, an effort that’s
gaining momentum even though it has yet to be embraced by
much of the medical and public-health community.
Not the sort to put much faith in the establishment,
Ayoub says that trust in government and mainstream medicine
can be badly misplaced.
“The debacle with Vioxx and other drugs should be a
warning,” he says. “The system can fail. Sometimes it can
Ayoub, 45, isn’t one to seek the limelight, but it often
finds him. At Peoria High School, he set a state track
record that still stands. At the University of Illinois, the
two-time All-American in track and field earned a Big Ten
title. In the honors program there, he was thinking fast,
too. He critiqued scientific studies weekly for two years
and says it helped him hone his ability to spot flawed
As an undergrad, in 1983, he broke another record when
his work was published in the elite journal Science.
The coup led to a flurry of national media coverage, and
Ayoub recalls being teased for being “sex-obsessed” by a
Peoria newspaper reporter because the study he co-authored
was focused on differences between neurons in the brains of
male and female juvenile macaque monkeys. “Sex differences
in the brain was a hot topic at the time,” Ayoub says.
Since then, Ayoub’s been teaching and practicing
radiology. He’s lived in Springfield 14 years and works
part-time at Memorial Medical Center in addition to carrying
out the duties of his post as director of the Prairie
Collaborative for Immunization Safety.
In 2003, while reading medical journals, Ayoub decided to
investigate breakthrough biomedical treatments at a Defeat
Autism Now! conference in Washington, D.C. “Once you attend
a DAN conference, you don’t come back the same,” he says.
Now he’s begging physicians to take a closer look at new
treatments and old problems. He’s summarized his exhaustive
research on an extensively documented CD, which he’s titled
The Science and Politics of Vaccine-Induced Autism.
He says that physicians can no longer afford to blindly
trust the literature.
Ayoub has joined forces with others, such as Springfield
lobbyist Laura Cellini, whose son Jonathan is autistic.
They’re pushing the Illinois General Assembly to pass
legislation banning the use of vaccines containing
thimerosal. The effort is similar to last year’s
unsuccessful push in neighboring Missouri, where a
filibuster in the state Senate killed the bill.
Illinois’ version, the Mercury-Free Vaccine Act, is
sponsored by Rep. Kurt Granberg, D-Carlyle. The bill
specifies that no one in Illinois under the age of 3 years
or who is pregnant may be given a vaccine containing more
than 0.5 micrograms of mercury per 0.5-milliliter dose, or
an influenza vaccine containing more than 1.0 microgram of
mercury per 0.5 milliliter dose. The bill was approved in
the House Feb. 16 by a vote of 115-0, and moved on to the
Senate, where it was set for first reading on Wednesday,
Feb. 23. The Senate bill is sponsored by Senator Mattie
Even if the bill becomes state law, Illinois could be
trumped by Congress, which is considering Senate Bill 3, the
Protecting America in the War on Terror Act of 2005. The
proposed federal legislation, which increases benefits for
the families of U.S. soldiers who die in Iraq, also includes
language protecting vaccine makers from product liability
under the guise of bioterrorism protection.
According to the Coalition for SafeMinds (Sensible Action
for Ending Mercury-Induced Neurological Disorders), a
nonprofit advocacy group based in Cranford, N.J., the
federal legislation would block civil claims for injuries
caused by mercury in vaccines. Lujene Clark of St. Louis,
president of nomercury.org, which serves as an information
clearinghouse for advocates of a thimerosal ban, says the
legislation would also prevent states from banning mercury,
regulating drugs, or warning citizens that
mercury-containing vaccines or other drugs may be dangerous.
Clark says it includes sweeping changes in
pharmaceutical-product liability, research, and the Vaccine
Injury Compensation Act, which already gives drug companies
With federal bills pending, states are moving fast to
pass mercury bans. Last year, Iowa and California passed
laws restricting the use of mercury in vaccines. Nine states
— including Illinois — are considering similar legislation.
The anti-mercury effort also extends to the dental
In Arizona, a bill to warn parents and pregnant women
that mercury fillings can harm the developing brain of a
child or a fetus has garnered bipartisan support. Another
bipartisan effort in New Mexico resolves to study the health
and environmental impact of mercury amalgam fillings.
This flurry of legislative action provokes reactions
ranging from skepticism to fear among many health
professionals. They contend that thimerosal’s critics are
alarmists, that an outright ban risks the return of dreaded
Dr. Lawrence Frenkel, professor of pediatrics and
microbiology at the University of Illinois College of
Medicine at Rockford, says people are being needlessly
“It’s the bogeyman,” says Frenkel.
“The level of thimerosal, or the ethylmercury [in
pediatric vaccines], is very, very low,” he says. “Yes, it
reaches the safety margin for methylmercury, but that’s not
been proven to be an issue or a problem.”
Frenkel says the risk doesn’t outweigh the consequences
of not getting children immunized.
“I’m old enough to have seen children suffer and die with
many vaccine-preventable diseases,” says Frenkel. “The
vaccines are better than the disease.”
Mercury occurs naturally in the environment, in either
inorganic or organic forms. According to the federal
government’s Agency for Toxic Substances and Disease
Registry, organic forms of mercury, such as ethylmercury and
methylmercury, have “a significantly greater toxic effect
than other mercury compounds.” Federal regulatory agencies
have set limits to the exposure from ingestion of
methylmercury — found in fish — but not ethylmercury, found
That doesn’t mean, however, that state and federal
agencies have failed to limit exposure to thimerosal. In
1982, FDA officials said that thimerosal was “not safe for
over-the-counter topical use.” Thimerosal has also been on
California’s Proposition 65 list of known reproductive and
developmental toxins for more than a decade. It was removed
from animal vaccines in the ’90s.
U.S. Rep. Dan Burton, R-Ind., chaired the oversight
committee that in 2003 produced a report on the use of
mercury-based vaccines titled Mercury in Medicine.
The committee heard expert testimony and examined research
from leading universities. Burton concluded: “It should be
crystal-clear by now that mercury is a toxic substance that
does not belong in pediatric vaccines.”
Drugmaker Merck & Co. Inc., still contending with the
Vioxx controversy, is one of the companies embroiled in the
thimerosal dispute. According to an internal memo obtained
by the Los Angeles Times, thimerosal was on Merck’s
radar as early as 1991. Merck executives expressed concern
that babies could be exposed to dangerously high thimerosal
levels. The memo noted that some 6-month-old children would
get a mercury dose “up to 87 times higher than guidelines
for the maximum daily consumption of mercury from fish.”
Eli Lilly and Co. introduced thimerosal around 1930 with
minimal safety testing. According to the Burton committee
report, a 1935 internal document noted that Merthiolate, the
brand name for thimerosal, was unsatisfactory as a serum for
use on dogs.
Mercury foes don’t like GlaxoSmithKline, either. The
pharmaceutical giant hired Dr. Thomas Verstraeten, a Centers
for Disease Control and Prevention scientist and lead author
of a controversial study published in Pediatrics in
2003. Activists criticized the journal for failing to
disclose that Verstraeten was now employed by GSK, a
vaccine-maker named in thimerosal litigation.
In June of 2000, Verstraeten had presented the results of
his review of vaccination data, which suggested a link
between thimerosal and neurological disorders. However,
after several drafts, the version published in Pediatrics indicated
that a link could not be confirmed.
National media headlines trumpeted that thimerosal had
been cleared, fueling the anger of parents who had seen the
original data showing a link. After much public outcry,
Verstaeten wrote to Pediatrics to say that the
results were inconclusive and more research was needed.
The controversy heightened when activists obtained
transcripts from an off-site meeting convened by the CDC in
2000. Vaccine experts — including pharmaceutical company
representatives — gathered to discuss Verstraeten’s
findings. According to the transcripts, Verstraeten said
that when he saw the literature, he was stunned because he
thought a link was plausible.
Advisory-committee member Dr. David Johnson said that he
was concerned enough that he did not want his grandson to
get a thimerosal-containing vaccine.
After analyzing the Verstaeten data, researchers at
SafeMinds found strong evidence of a link. A SafeMinds
release reports that Verstaeten’s initial analysis indicates
that CDC officials were aware in 1999 of an 11-fold increase
in autism risk among children who received
thimerosal-containing vaccines. Noted impairments included
“an unspecified developmental delay,” ADHD, tics, language
and speech delays, and “the entire category of
In 2001, the CDC commissioned the Institute of Medicine
to examine the thimerosal-autism evidence. The IOM’s first
analysis found the hypothesis “biologically plausible” and
called for further research. A 2004 reanalysis rejected any
According to nomercury.org’s Lujene Clark, IOM
committee-meeting transcripts were leaked and turned over to
authorities. The transcripts suggest that CDC officials
pressured committee members.
“The CDC contracted and paid for this series of reports
from the IOM,” says Clark. “They made it very clear that
they wanted the IOM to give the nod, to say that ‘We see no
problems.’ That’s very, very frightening.”
Emerging evidence suggests that mercury was the last
biochemical straw for some kids — especially those who got
187 micrograms of mercury during the first six months of
life. Autism may be caused by a genetic predisposition
triggered by heavy metal or pesticide insults that damage
Dr. Jill James, a University of Arkansas biochemist,
recently published a study showing that kids with autism
have a highly abnormal metabolic profile. “They have very
low levels of … glutathione,” says James. “Glutathione is
well established to be the major mechanism of mercury
detoxification and excretion.
“Given an equal exposure to heavy metals — and we’d want
to focus on any of them; mercury could be one, arsenic, lead
— if you’ve got less glutathione around, it’s going to be
Scientists have found heavier body burdens of mercury in
autistic kids, implying an impaired ability to get rid of
the heavy metal. Additional research has found that
thimerosal induces DNA breakage, membrane damage, and cell
death in human neurons. Inherited DNA breakage could leave
each subsequent generation more vulnerable to heavy-metal
Replicated studies of baby hair and teeth have shown that
autistic kids have lower mercury levels, again implying that
these children’s bodies retain mercury.
“These kids with autism have three times as much mercury
in them,” says Dr. James Adams, chemical-engineering
professor at Arizona State University. “You know there’s
something very wrong with their mercury metabolism.”
Other findings include evidence of brain inflammation,
gastrointestinal inflammation, and autoimmune activation in
autistic kids. The authors of a breakthrough Columbia
University study reported that they induced autism in mice
with the suspected genetic predisposition by giving them
vaccine-comparable doses of thimerosal.
With all of the mounting evidence, David Ayoub wonders
why vaccine makers are still putting 25 micrograms of
thimerosal in flu vaccines given to babies, pregnant women,
and senior citizens.
For the first time, the CDC recommended this year that
babies get flu shots earlier, at 6 months of age. Pregnant
women were also encouraged to get flu shots.
The package insert for Fluzone — an influenza vaccine
distributed by Aventis Pasteur — states, “It is not known
whether Influenza Virus Vaccine can cause fetal harm when
administered to a pregnant woman or can affect reproduction
“The EPA’s allowable daily exposure limit is 0.1
micrograms per kilogram of body weight,” Ayoub says. “To
meet this guideline, those who receive a flu vaccine must
weigh at least 550 pounds. The fetus would receive a dose
exceeding federal limits by several hundredfold.”
In 2000, an FDA neurotoxicology study found that
thimerosal crosses the placental and blood-brain barriers.
According the CDC, one in 12 women of childbearing age has
an unsafe level of mercury in her body, putting newborns at
“There is as far as I know no definitive plan . . . to
remove mercury from flu shots,” Ayoub says.
According to an Aventis Pasteur spokesman, the world’s
largest flu-vaccine producer, supply is not an issue.
“This is the third year that we’ve produced the
preservative-free formulation,” says spokesperson Len
Lavenda. “We have never sold out — even this year, or last
year, when we had a shortage.
“They [healthcare providers] have a choice. Both
formulations are approved by the FDA for people aged 6
months and older . . . I think the preservative-free is a
little more, but we’re not talking dollars more — it’s cents
Ayoub says that shows why voluntary removal doesn’t work.
“A law banning thimerosal is necessary,” Ayoub says.
“Voluntary removal or reduction doesn’t assure safety.”
Parents say the best way to restore public confidence is
to “come clean” and fix a broken system.
“Get the mercury out,” says Lujene Clark, “and reassure
parents that you are finally starting to make decisions in
the best interests of the citizens.”
Ayoub agrees: “The autism epidemic is largely the result
of heavy pharmaceutical industry influence. To prevent
future tragedies, we need major reform.
“Exposure of the truth is the first step.”