“On a mission to discredit any and all evidence of a mercury-autism linkage”

Like most bloggers, I suspect, I like to know who’s linking to me. Unfortunately, the majority of bloggers appear not to use TrackBacks, and even when they do for some reason the TrackBacks often don’t register. Couple that with a level of comment spam that sometimes outnumbered my legitimate TrackBacks by at least 200:1, and you see that TrackBacks aren’t a great way of knowing who’s linking to you. Consequently, a couple of times a week, I do quick Technorati and Google Blog Searches on the URL of Respectful Insolence to see who happens to be linking to me.

That’s how I found this brief mention of my article on how that mercury militia luminary Dr. Mark Geier lost and lost big in a recent court case in which the plaintiffs were suing a company based on the claim that thimerosal in RhoGAM had caused their child’s autism, a ruling in which the judge administered a truly deserved epic slapdown of Geier’s testimony, qualifications, and science. This ruling gave me hope that the legal system might actually do a better job dealing with pseudoscientific claims of vaccines causing autism than it did with cases against manufacturers of silicone breast implants. Indeed, it was almost as satisfying to read as Judge Jones’ even more epic slapdown of “intelligent design” creationism in Kitzmiller v. Dover.

Apparently, the owner of the blog, Charles Fox, is a lawyer, and he had commented himself on my own article on the Geiers. His blog, Special Education Law Blog, focuses on special needs law and cases.

Here’s what he said about my article:

There has been a recent case where the science linking between mercury and autism has been thoroughly rejected. The author of the article seems to be on a mission to discredit any and all evidence of a mercury-autism linkage.

Uh-oh. It looks as though Mr. Fox is humbly requesting a dose of Respectful Insolence™ of Orac. And Orac is almost always willing to grant such requests.

I’ll just take this opportunity to set Mr. Fox straight. I don’t need to “discredit any and all evidence of a mercury-autism linkage.” It’s already been discredited in the one way that truly counts: through the science. Each new study that comes out is yet another nail in the coffin of this dubious hypothesis, which sounded superficially plausible scientifically a few years ago but hasn’t been supported by the science since, with each new well-designed basic science and epidemiological study failing to support such a link. Indeed, just this month, yet another large, well-designed epidemiological study has failed to find any linkage whatever between mercury and autism (or MMR and autism as well). In fact, autism rates in the study population continued to rise at the same rate after thimerosal was removed from vaccines in 1996.

The only reason that the postulated linkage between mercury and autism fails to die, not unlike a certain undead dictator that keeps popping up on my blog from time to time, is not because of the science, which killed it dead at least a year ago, but rather because a dedicated contingent of activists keep agitating and “investigators” such as Mark and David Geier (most prominent among this group) keep churning out studies chock full of bad statistics, bad medicine, bad science, and dubious ethics, often published in dubious antivaccination “journals” that purport to “prove” a link and use this “link” to justify using powerful and expensive sex hormone suppressing drugs like Lupron to “treat” children with autism. Never mind Dr. Geier’s financial incentive, as he makes a considerable amount of money treating autistic children with chelation therapy (and now Lupron) and has even applied to patent his Lupron protocol.

To me, it’s obvious that the insinuation behind Mr. Fox’s claim that I am on a “mission to discredit any and all evidence of a mercury-autism linkage” is to imply so much bias in my opinion that I should not be taken seriously on this issue. My retort to that is that the only “bias” I have is that I highly value evidence-based medicine, sound science, and good epidemiology. Unlike the mercury militia’s reaction to recent studies casting doubt on their pet hypothesis, if I were presented with a well-designed basic scientific or epidemiological study that actually did suggest a link between thimerosal and autism or a well-designed clinical trial that showed that chelation therapy for autism actually did something other than line the pockets of chelationists with greenery and put autistic children at risk, I’d definitely rethink my position. No such studies exist. His comment also seems to try to paint me as some sort of fanatic. Nothing could be further from the truth. What I try to do is to combat pseudoscience and quackery. I’m not out to “discredit” sound science. I wish I didn’t need to try to discredit unsound science, but the mercury militia’s activism and the truly shoddy and biased science used to “prove” a link between mercury and autism leaves me little choice.

Mr. Fox, however, seems to have a bias of his own, namely that there is something to the claim that mercury causes autism. He approvingly quotes a study that he apparently found convincing as evidence for a link between heavy metals and autism. Not Mercury has pointed out its many flaws (particularly its probably fatal flaw of using ratios of urinary markers to creatinine rather than measuring 24 hour excretions of these markers), and Kevin Leitch has also pointed out that some of the investigators in the study are anything but unbiased. Worse, he seems to believe that chelation can actually help, when in reality for treating autism chelation therapy is nothing more than quackery, and potentially dangerous quackery at that.”

To be fair, the mercury-autism issue only takes up a small portion of posts on Mr. Fox’s blog, and, as The Probe (who has ample reason to know) informs me, there’s actually a fair amount of decent information there. However, he undermines the useful information by mixing it with commentary like this regarding a lawsuit over thimerosal:

The case is far from a certainty as the plaintiffs still have to prove that the mercury/thimerosal caused the child’s autism; this argument has strong proponents and opponents each armed with studies and research. Even if this suit fails it is still an important round one in what promises to be the beginning of many such cases. The tobacco cases went on for years with the defendants winning every case until the fairly recent past. At the very least the arguments and science that link autism and mercury/thimerosal will finally get a full hearing before a jury and a court with powers to order damages that actually compensate the full measure of harm.

The big difference is that the scientific, clinical, and epidemiological evidence that tobacco smoking can cause lung cancer and other life-threatening conditions like heart disease is overwhelming to the point of being scientifically indisputable and has been for decades. In contrast, the evidence supporting the claim that mercury from vaccines causes autism is junk science of the worst order and getting weaker with each new study. It didn’t pass muster with Judge Beatty, and, if the Daubert standard is correctly applied, it’s highly unlikely to pass muster in any other court, given how work by the Geiers, Boyd Haley, etc. all reference each other. A commenter on my own blog (whom I’m going to steal from) put it quite well:

Why did Big Tobacco start losing lawsuits after winning all of the early ones? It had nothing to do with science, because the science was on the side of the plantiffs for the longest time. No, lawyers started winning more often when they took the tact not that cigarettes were defective (because they weren’t – they did what they were designed to do) but that the manufacturers of cigarettes lied about the risks. It’s one thing to say “cigarettes are bad for you, if you want to smoke go ahead”, quite another to downplay or dismiss the risks altogether.

This is the crux of the mercury militia’s case – that drug companies knew thimerosal could cause neurological disorders and continued to put it in vaccines. The problem with that argument is that unlike Big Tobacco, there is very little evidence that thimerosal plays even a minor role in such conditions. And it goes without saying there is even less evidence that drug companies knew that thimerosal could cause these conditions and chose to cover it up. If the best “smoking gun” you’ve uncovered in all your months and years of discovery is a memo from Maurice Hilleman expressing concern about thimerosal content in vaccines, then you’ve got no chance to win a lawsuit.

Indeed, even the “mercury militia” is starting to see the writing on the wall and reluctantly being forced to start to face reality by the weight of the evidence. As Kevin Leitch points out, they are mentioning mercury in vaccines less and less and starting to be more vague, listing mercury among “other” vaguely specified environmental factors or even switching their attention to aluminum compounds in vaccines. (Of course, to them, it still has to be the vaccines, putting the lie to their claims that they are not antivaccination, but that’s the topic for another post.)

What’s kept the myth that mercury in vaccines causes autism alive is not science, but rather a combination of factors, including a group of parents who, when faced with an autistic child, have difficulty accepting that their child was almost certainly born that way; a general suspicion of big pharma, vaccine manufacturers, leading to a tendency towards conspiracy mongering; plus a veritable industry of quackery that’s sprung up to offer false hope that these children can somehow be miraculously “cured” with modalities like chelation therapy or Lupron. These people are egged on by “journalists” like David Kirby (who seems to be becoming a bit quieter about the mercury-autism conspiracy-mongering lately and has been busily shifting the goalposts as far as what epidemiological evidence would convince him that there is no link between thimerosal and autism) and activists like Robert F. Kennedy, Jr. (who, unfortunately, is like the Energizer Bunny on this issue). If Mr. Fox wants to perceive my position as being “on a mission to discredit any and all evidence of a mercury-autism link,” he’s only partially correct. I’m on a mission to discredit pseudoscience used to “support” a mercury-autism link and the quackery to “treat” autism that flows from that pseudoscience. Show me some credible evidence from well-designed scientific experiments and clinical studies that truly does suggest a link, I will consider it with an open mind, but with the usual skepticism that I try to apply to every scientific paper that I read.