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Debating the Causes of Autism

Dear Readers,

Dr. Marc Siegel

August 3, 2005

Dear Readers,

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There follows a group of letters on mercury, thimerosal and vaccines. Those of you who have been following my column know that this has been a recurring topic. I will respond to the letters individually, but I also wanted to start the column with a general statement:

Drug companies manufacture vaccines, several of which are mandated for use by our infants. Despite the vulnerability the public has to chemicals introduced into our bodies, the drug companies tend to be defensive and laissez faire about the need for changing they way they do things. Thimerosal is such an example. This additive, which contains trace amount of mercury, has been shown to cause irritability in mice, and could well have been removed from routine vaccines long ago. But this is not the same thing as concluding that thimerosal causes autism, as many people argue.

To be sure, there is a significant increase in autism and environmental factors appear to play a role as does improved diagnostic sensitivity to autism. But in several epidemiological studies, no association between autism and thimerosal has been proven. Does this mean that no such association exists? No, it does not. Further study, perhaps even a large prospective double blind randomized trial, may be warranted.

In the meantime, I am concerned that all the attention paid to thimerosal takes the focus away from a much larger issue: We Don’t Know why autism is on the rise. Too much thimerosal-mongering distracts us from a true scientific investigation of what is really causing all the autism. Too often, we need to know answers right away and we (the public) use this impulse to latch on to the first explanation we can find. This does science a disservice. You’ll see from the letters that follow that I take much heat from consumer advocates on this subject. I don’t take it personally, and in fact I welcome these letters. I am concerned, however, that the vehemence is misdirected towards me. We are on the same side, after all.

Our federal health agencies continue to state that their research shows “no evidence of harm” from injecting our children with vaccines containing mercury. The press generally publishes these claims because these agencies are charged with safeguarding Americans’ health. However, the members of the media rarely note that these are the same people who approved and mandated the vaccines in the first place. They’re also the ones with the 700 conflict of interest waivers for financial ties to the drug industry. The reality is that there has never been any long-term study done on the toxic effects of mercury (thimerosal) used in vaccines.

Our federal health agencies continue to have no valid explanation for the dramatic increase in autism. The FDA and the CDC tell us that this may be due to “better diagnosing” or some elusive “autism gene.” By definition, you cannot have a genetic epidemic. Therefore, there must be an environmental trigger. The federal health agencies adamantly deny that the autism increase could be the result of toxic mercury allowed in vaccines in the late 80’s through today. Yet, they are slow to look for any other environmental trigger. If not mercury, then what? Federal agencies have assumed an indefensible stance, claiming that the admitted excess mercury they allowed in vaccines for the last 20 years doesn’t cause mercury poisoning. While they are in denial, America’s children are suffering.

ANNE MCELROY DACHEL, Chippewa Falls, WIMedia Relations Coordinator, National Autism Association

Dear Anne,

I agree with you that autism is a significant and growing problem and that the effects of thimerosal have not been fully studied. But this is still not the same thing as concluding that thimerosal causes autism. Current evidence does not show that. We need prospective randomized trials to study cause and effect.

If mercury is not linked to Autism in children then please explain why my Autistic son tests extremely high for Mercury and why he has a secondary diagnosis of Severe Limb Apraxia . The two most common causes of Limb Apraxia are stroke or exposure to neuro toxins. According to my son’s neurologist my son has the IQ of 105 and the motor skills and social skills of a 3 yr old at age 7

ANGELA MCDONOUGHTaneytown MD

Dear Angela,

I am very sorry to hear this about your son. I would make the following points, however, only because you wrote me, it is certainly not my intention to upset you further.

  1. 1) I am not saying that your son’s mercury level is unrelated to his autism. That remains to be proven, but mercury is most certainly a neurotoxin and his limb apraxia may also reflect that.
  2. 2) Even if his condition is mercury-related, it is not clear that that mercury came from the trace amount found in thimerosal. There is plenty of mercury in the environment these days.
  3. 3) Thimerosal should not be used in vaccines; I have stated my position on this clearly.

I wish you all the best in caring for your son.

As the parent of an “autistic” child with inflammatory bowel disease, seizures, antibodies to myelin basic protein, high TNF and IFNg and vaccine strain measles in his bowel and cerebral spinal fluid I find it necessary to write to you. The studies which were conducted by CDC to refute any correlation between vaccines and autism went through 6 different drafts; the database known as VSD has been kept from independent verification by researchers; the author of the study, Thomas Verstraeten has been quoted in Pediatrics stating that the CDC study proves nothing. The other study in Denmark has similar flaws. You should be aware that the Institute of Medicine in a recent report that you can purchase and read has advised that the CDC Vaccine Safety Datalink data be made public and that CDC employees who destroyed datasets get legal counsel; also the very next day the head of CDC removed Dr. Robert Chen from the vaccine program. Low levels of thimerosal can cause a great deal of damage both to a developing nervous system and immune system.

The use of thimerosal in vaccines has contributed to the pandemic of autism in this country and the response of our federal health agencies has been pathetic, perhaps even criminal. I suggest you buy a book called “evidence of harm” and read it; it details the coverup in a well researched manner; how do I know; I was the attorney who was responsible for the investigation of Merck, Eli Lilly, the FDA and CDC on behalf of the Committee on Government Reform.

ELIZABETH BIRTEvanston, Illinois

Dear Elizabeth,

I agree that thimerosal should have been removed from vaccines a long time ago. It has been removed now, and should be kept out of all vaccines, especially those given to infants. I have no knowledge of what the CDC has done in this regard–though my personal experience with this agency is not one of cover-up or suppression but more one of scientific inquiry which is unfortunately–all too often–tied to public trumpeting and sweeping general statements. I believe that there needs to be further study into what is causing the increased incidence of autism. I remain unconvinced that the cause has already been proven to be thimerosal.

The only doctors who will be left defending the statement, “There is no association of thimerasol to autism”, will be the very stupid, stupid, stupid doctors. You might as well jump onto the train of TRUTH because there is nothing that is going to stop all the parents who have had to endure the damage caused by injecting their infants with buckets-full of neurotoxins before they were even six months old. We are outraged and sick of the lies.

LINDA SODERBERGSan Francisco, CA

Dear Linda,

I am not saying there is no association between thimerosal and autism. I am saying that a cause and effect has yet to be proven, and that a premature conclusion without further scientific inquiry and full blown studies will obscure other potential culprits.

People have lots of reasons for turning away from Western medicine–the expense (especially for the under-insured), a fundamental distrust of doctors, a feeling that it fails to address important questions of wellness (rather than simply the absence of disease). But alternative treatments aren’t regulated in the same way as traditional western medicine is and can be dangerous (and also expensive). Is there an authority to answer questions about these topics that isn’t funded by some herbal supplement company out to make a buck? I’ve just started seeing a chiropractor, and I’m terrified of the potential for paralysis, but I’ve never had a doctor say anything either way about it. My friend wants to try a 10 day “colon cleanse”, but doesn’t have any idea what effect it might have on her ability to function (and she’s a 911 dispatcher, she needs to function). My husband, a coder, has severe RSI in his arms and wrists and is willing to do practically anything to avoid the surgery. Is there somewhere to turn for scientific evidence of what works and what doesn’t, or am I stuck with very risky trial and error? And why on earth do government bodies not cover or regulate these treatments?

SANDRA SEAMANSeattle, Washington

Dear Sandra,

Alternative treatments need to be better regulated–I agree with you–though I’m not sure that would ensure quality of care any more than it is doing currently with traditional medicine. In terms of chiropractors, I do not believe they are dangerous, but it is not generally their scope to be diagnosing neurologically. I would suggest you see a neurologist before submitting to manipulations or at least have a diagnostic work-up to determine the cause.

Dr. Marc SiegelDr. Marc Siegel is a practicing internist and an associate professor of medicine and a fellow in the Master Scholars Society at New York University School of Medicine. He is a weekly columnist for the New York Daily News, a frequent contributor to the Los Angeles Times, the Washington Post and The Nation. He is a member of the board of contributors at USA Today. He appears frequently on CNN, the Fox News Channel, and the NBC Today Show. He is the author of False Alarm: the Truth About the Epidemic of Fear and most recently, Bird Flu: Everything You Need to Know about the Next Pandemic (Wiley).


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