Thimerosal and Autism: No Link
It has long been an article of faith amongst some autism advocates that the type of mercury found in thimerosal was the cause for autism. Arthur Caplan in an article in the Philadelphia Inquirer that debunks this claim, not that I expect those who advocate this position to be swayed by the evidence.
What must it be like to spend a huge amount of time every waking day trying to change public health practice – only to find out that you were wrong?
That is precisely what has happened to the proponents of the theory that mercury in vaccines – contained in the preservative thimerosal, which once was used (and is used no longer) in vaccines – is responsible for a nearly 20-year explosion in autism and other neurological disorders among American children.
This urban legend has had very real – and terrible – consequences. It has led, and continues to lead, many parents to avoid getting their kids and themselves vaccinated against life-threatening diseases. The failure to vaccinate has caused many preventable deaths and avoidable hospitalizations from measles, whooping cough, diphtheria, flu, hepatitis and meningitis. And fear of vaccines puts each one of us at risk that we, our children or grandchildren will become part of a deadly outbreak triggered by someone whose parents avoided getting their child vaccinated for fear of autism.
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Recent research on many fronts in medicine and science has nailed the coffin shut on the mercury-in-vaccines-causes-autism hypothesis. The connection is just not there. Perhaps the key fact, which has garnered little attention, is that thimerosal has been removed from vaccines in this and other countries for many years, with no obvious impact on the incidence of autism. The most recent data point toward a correlation with nothing at all to do with vaccines: the increasing age at which people (particularly men) have children seems to be associated with an increase in autism and other neurological problems.
You’d think this would be obvious. If thimerosal has not been added to vaccines for decades and there has been no change for the better in the rates of autism, then one would think that thimerosol and the mercury in thimerosal was not the culprit. Add on that there is another factor that is correlated with autism (and yes, I’m quite well aware that correlation is not cuasation, but it can be suggestive) and like Prof. Caplan says, you have the final nail in the coffin.
Still, some of the most fervent anti-vaccine critics cannot let go. They continue to tell devastated parents of children with autism that vaccines are to blame. Others are still out on the lecture circuit peddling books and articles that bash vaccines and invoke mercury as a problem. Still others pepper the Internet with the false message that vaccines and autism do go hand in hand – it is just that the government, or the pharmaceutical companies, or organized medicine, or all of them, are keeping the truth from us all.
Less than two years ago, Robert Kennedy Jr. published an article in Salon.com alleging that the government knew of and covered up the autism-vaccines connection. Thimerosal was, Kennedy told large audiences and many media reporters, to blame.
Well if there was every any doubt that Robert Kennedy Jr. was an idiot, this will hopefully remove that doubt. The problem with the autism crowd is that they are what are sometimes referred to as woo-woos and for them their beliefs have taken on an almost religious aspect.
Take for example this website. It claims that the link between autism and thimerosal is a fact and has a list of facts,
1. Mercury is hazardous to humans. The use of a toxic poison as a preservative is undesirable, unnecessary and should be eliminated entirely.
Actually there are two types of mercury, methyl and ethyl. Methylmercury is bad, but the toxicology of ethylmercury is not well studied and hence the supposed fact is actually speculation.
2. For decades, ethylmercury was used extensively in medical products ranging from vaccines to topical ointments as preservative and an anti-bacteriological agent.
Notice how they don’t tell the reader that mercury comes in two forms and implies that ethylmercury is as dangerous and methylmercury. Right here we see some pretty egregious dishonesty form a site that claims to be honest and in the fight against autism. I suppose the latter part is true, the the former part is highly questionable.
The bottom line here is that thimerosal is no longer in vaccines. Vaccines do carry small risks of illness and even death. However, vaccines also prevent illnesses, death and disability with far, far greater likelihoood. So if you are a new parent, get your kid vaccinated.
There is no amount of evidence that will dissuade advocates from the idea that thimerosal is the primary cause of autism. Simple reason: rent-seeking. You can probably find someone somewhere whose autism was caused by thimerosal by the idea that it’s the primary cause (or even a major cause) has been so thoroughly debunked so many times in so many places that it’s clear the advocates just aren’t listening any more.
I think there are two main reasons people won’t let go this argument and the MMR/autism one. The first is that there is possibly some money to be found through lawsuits, and the second is that so many parents are desperate to want to know “why” their child has autism.
I have a child with autism, and I haven’t ever bought much into the vaccine link, I mostly think it is a genetic cause-or at least with a major genetic predisposition that is triggered by some unknown cause.
There is a lot of snake oil being sold to parents of children with autism, from the causes to the treatments, and some parents who have boughtinto the snake oil just can’t let it go.
Call me crazy, but shouldn’t they have to prove that it isn’t harmful? in other words the burden of proof is on the people wanting to add the possible dangerous chemical to injections.
Assuming what you are saying here is true these people deserve to be sued, maybe not for causing autism, but for using a material in an injection without adequate testing.
You can’t prove something is not harmful. In fact, vaccines always carry a risk of illness or even death. The risk is very, very slight and the benefits are very, very large, but vaccines are not harmless in the sense that if you give them to enough people, eventually somebody will have an adverse reaction.
But your point of greater study prior to use is a good one, at that was one of the reasons for discontinuing the use of thimerosal. However, from what I’ve read at the FDA’s website, thimerosal and ethylmercury are not the same as methylmercury. For example, methylmercury will be removed from the body very slowly, whereas ehtylmercury is removed fairly quickly even in infants.
As for thimerosal, it has been around for sometime and used as a preservative for quite awhile, so I don’t know if that would work. And suing somebody for using a compound that does what it is supposed to do (preserve vaccines–i.e. prevent other illenesses and problems) and that most consider harmless today is really setting both a horrible precedent and perverse incentive, IMO.
“Mercury” is one of those magic words, like “Genetically Engineered”, “Nuclear”, “Irradiated”, or “Cloned” at which unthinking people go into immediate panic mode. Enough fear-chum has been cast into the waters of public discourse that the slightest whiff is enough to cause a frenzy.
And frenzy–expensive, litigious, damaging frenzy–it is. No need to think; just react.
I’m sure I’m not the only person in the US who, as a kid, played with liquid mercury. We used to rub it on pennies to make them shine like dimes. (Leaving the new ‘dime’ in a potato overnight dulled the mercuric shine, making them easier to pass.) We played games with mercury, shooting globules across a surface like marbles. And we almost never washed our hands before putting them near our mouths or other mucus membranes. Somehow, we’re still alive, flourishing even after having mothered and fathered perfectly healthy kids. It’d be hard to prove our IQs took a hit as a consequence.
But now, the presence of a drop of mercury will certainly shut down a school and call for a multi-thousand dollar clean-up by the environmental hazard people.
This is a ratchet that been cranked a bit too far, IMO.
Not rigorously prove it in the sense of proving a universal negative (this compund does not cause harm) but you can and certainly do test and develop enough statistical data so as to say with some confidence “this doesn’t appear to be harmful.”
That’s what we have an FDA for.
John:
Liquid elemental mercury isn’t very dangerous. It is the mercury compounds that are problematic. Of course by introducing mercury into a living system you are putting it into a place ripe with potential compounds for the mercury to glom onto. I work with liquid mercury as part of my job. It does form fumes but at a very low rate. Other than inalation it is safe unless it gets in an open wound or into a mucous membrane. Still the stuff is pretty nasty of any of this happens and can cause chronic poisoning effects (i.e. the changes are gradual and build up over time so you may not even realize anythig is wrong).
A coworker uses a tool that has an Xray source and we were debating which is the bigger risk to deal with the other day.
I read that wrong, and thought it said you rubbed mercury on your penis to make it shine like a dime!
That is pretty funny.
Regarding testing and the FDA, my reading of this is that thimerosal was in use prior to the existence of the FDA (1931 vs. 1938), by a number of years. Nobody problably thought much about it because there weren’t many vaccines. It wasn’t untile the schedule of vaccines started to increase dramatically and when autism also started to increase that people thought their might be a connection.
Tlaloc-I think for the most part it has been proven, at least as much as you can.
I think one huge piece of evidence is that mercury has been removed from vaccines in European countries for about 15 or more years. In the US for about 7 (seems like around 2000 is when they stopped using thimerasol).
But European countries saw a similar rise in rates of autism as the US during the period, when they had no thimerasol, but we did. It has been out of vaccines for a relatively long period, but rates of diagnosis aren’t decreasing.
The one vaccine/autism link that is kind of interesting, but I think is kind of unprovable is the theory that the vaccines themselves overload the immune system and cause kids to develop autism.
But then for me, I am still mostly a genes related theorist, mostly because I can look back on my sons infancy-his behaviors, and even his photos (he never made direct eye contact with the camera-even facing the camera, his eyes would be looking somewhere else), all just seem to point to his autism-we just didn’t know at the time what was going on. He was fully vaccinated, but many of the behaviors were actually there before he got his first vaccines.
There was, and may still be, a theory that autism has a higher than normal incidence in children of “counters”, and “coders”.
The children of The Silicon Valleys of the world have a higher incidence of the syndrome, perhaps because two parents are of the type that have superior computer programing skills, and generally poor interpersonal skills.
I can’t see why older fathers would be a phenomenon of the last 20 years, a time when an increase in Autism has been cited.
Tlaloc: Even as children, we learned not to put mercury on gold….
BTW, does anyone recall a Scientific American article of some five or so years ago that reported on a link between autism and a gestational hiccup around week 19? That still, to me, seems the most likely piece of causation. But I’m certainly ready to accept that there can be several causes.
Been debunked over and over again.
The sad thing is the news that the guy who published the hopelessly discredited “study” implicating MMR was paid by lawyers to do the “research” and publish it so there’d be grounds for lawsuits. It’s like something straight out of Warren Meyer’s BMOC.
Those people and their brain donor cult followers have already caused too many deaths.
BTW, does anyone recall a Scientific American article of some five or so years ago that reported on a link between autism and a gestational hiccup around week 19?
I hadn’t seen this one. But a year or two ago I read an article on what studies were being done (ie they were current studies working with a hypothesis, they hadn’t been completed yet). Some regarded genetic studies with siblings, but one that I found interesting was illness in the mother while pregnant requiring the use of antibiotics-that one always kind of interested me, because I had multiple infections during my pregnancy with my son.
My money is still somewhere on the genetic link, especially since autism tends to cluster in families.
What must it be like to spend a huge amount of time every waking day trying to change public health practice – only to find out that you were wrong?
The same may be said about Global Warming 10 years hence.
Not rigorously prove it in the sense of proving a universal negative (this compund does not cause harm) but you can and certainly do test and develop enough statistical data so as to say with some confidence “this doesn’t appear to be harmful.â€
Such studies were done repeatedly, beginning in the 1930s. The best science has always indicated that thimerosol was safe.