The mercury autism debate continues. While not a subscriber to the mercury vaccine/autism link I do not think debate and discussion should be closed on this or any other subject related to autism. Toxicologist Michael Wagnitz seems somewhat more qualified to present information on the "mercury" side of the debate than David Kirby and presents some interesting points in rebuttal of Psychiatrist Dr. Eric Fombonne.
The mercury, autism debacle: How stupid do they think we are?
Michael Wagnitz
May 7, 2007
Last weekend the Sixth International Meeting for Autism Research took place in Seattle. The meeting claimed to draw the top 900 autism researchers and scientists from around the world. One of the key participants was Dr. Eric Fombonne of Montreal Children's Hospital at McGill University. Dr. Fombonne, a psychiatrist, presented his research on mercury. His work involved testing the blood and hair of 147 children. Roughly half of his subjects were diagnosed with autism and half were considered neurologically typical controls. He found no difference in mercury levels in the patients hair or blood.
The first question one might ask is why a psychiatrist is considered qualified to do toxicological work. Most parents are concerned about the mercury exposure that their children received as newborns and infants from mandatory vaccines. The vaccine schedule in Canada, where Dr. Fombonnes study was done, and the United States were quite different in the 1990's. Dr. Fombonne,s patients were not tested after vaccination. If he had talked to any reputable toxicologist, they would have told him that the ethylmercury from vaccines clears the blood in about seven days. Ethylmercury, a short-chain alkyl mercury compound, is rapidly distributed to the brain, kidneys and other tissue. The hair tested would need to be from a first haircut to show this mercury exposure. Even if this was the case, research has shown that autistic kids do not excrete mercury efficiently. The hair would not contain any measurable amounts of mercury. It's to bad that McGill University does not have any toxicologists who could have explained to Dr. Fombonne that his work was a waste of time and money.
If one was really interested in determining the body burden of mercury they would perform the urinary porphyrin profile analysis (UPPA). Porphyrins are precursors to heme, the oxygen carrying component of blood. Mercury inhibits the conversion of specific porphyrins to heme. This test is backed by decades of published research. Recently it was shown in two published, peer-reviewed studies, that mercury inhibited porphyrins were significantly higher in autistic patients when compared to age matched controls (1)(2). The other way to test for mercury in the body is by using a provoking agent and measuring mercury in the urine.
The organizers of this meeting did not reveal that when Dr. Fombonne isn't conducting epidemiological studies or doing heavy metal analysis, he is appearing on behalf of vaccine manufacturers defending the safety of mercury. Dr. Fombonne refers to the amount of mercury in vaccines as "trace". Again, if he were a toxicologist or chemist, he would realize that the concentration of mercury in a multi-dose vaccine vial is 250 times higher than what the United States Environmental Protection Agency (EPA) classifies as hazardous waste.
References:
(1) Nataf R, Lam A, Lathe R, Skorupka, C. 2006. Porphyrinurea in Childhood Autistic Disorders: Implications for Environmental Toxicity. Toxicol. Appl. Pramacol. 214(2):99-108
(2) Geier M, Geier D, 2006. A prospective assessment of porphyrins in autistic disorders: a potential marker for heavy metal exposure. Neurotox Res. Aug;10(1):57-64
About the Author: Michael Wagnitz has over 20 years experience evaluating materials for toxic metals. He currently works as a chemist in the toxicology section of a public health lab evaluating biological samples for lead and mercury.
Michael Wagnitz
http://www.americanchronicle.com/articles/viewArticle.asp?articleID=26477
1 comment:
I am happy that you don't subscribe to the mercury-autism link. And I'd like to ask Dr. Wagnitz the same question: How stupid do you think we are?
Let's begin with Dr. Wagnitz's challenge that "a psychiatrist is considered qualified to do toxicological work". Dr. Fombonne isn't the only author of the work in question. He has three co-authors (the abstract of the presentation is accessible at http://www.cevs.ucdavis.edu/Cofred/Public/Aca/WebSec.cfm?confid=281&webid=1514). I suppose that at least one of the co-authors is a toxicologist; I don't want to waste time to check. But even if not, is it so important? Every MD has received some toxicology training. Biologists like me regularly participate in medical research and vice versa. In fact, some major breakthroughs in science have been achieved by researchers without formal training. So, to my opinion, ability to do research is more important than what is written in the diploma. I searched PubMed for "Fombonne E" and "Wagnitz M" and the first search gave results, the second one didn't. So, although I'm not a toxicologist, I feel qualified to argue with Dr. Wagnitz as an equal, because we have the same number of published articles on autism (that is, 0).
Dr. Fombonne's abstract doesn't contain a word about vaccines. It is about mercury exposure, which could come from many sources but in this case not from vaccines because the children had mean age 4 and so most of them shouldn't have received mandatory thimerosal-containing vaccines. So after which immunization exactly should the patients have been tested, according to Wagnitz, and what have the immunization schemes in the 1990s to do with autism in kids not conceived at that time?
Having the above in mind, you see that the discussion of how rapidly mercury clears from the blood is nonsense. The sources of mercury for Fombonne's patients were UNKNOWN. The exposure could have been either incidental or continuing. In the second case, mercury of course would be present in blood, urine and hair in relevant concentrations. In the first case, the researchers couldn't know the time of mercury exposure, so the best they could do was to do the measurements shortly after the diagnosis - which they did.
My PubMed search for "mercury urinary porphyrin profile" produced only 7 articles, of which 6 listed JS Woods as co-author. This of course doesn't mean that the method is irrelevant, but clearly shows that it is preferred by one group of researchers, rather than being universally accepted among toxicologists. As for the sentence "The other way to test for mercury in the body is by using a provoking agent and measuring mercury in the urine" - I've already mentioned in a previous comment that this method isn't popular in toxicological studies available in PubMed.
And now, let me return to the earlier Wagnitz's notion that "autistic kids do not excrete mercury efficiently". He gives no reference but I guess he means the work of Kern et al. (2007), Sulfhydryl-reactive metals in autism, and the references therein. These authors, finding lower hair content of mercury and other metals in autistic vs. control children, suggest that "children with autism may have trouble excreting these metals". (My own explanation is that parents of autistic kids take more care to feed them "healthy, organic" foods and to spend time in unpolluted environment.)
Bad science is characterized by faulty study design, methodological errors or data misinterpretation, but its root cause usually is failure to accept and apply the scientific method. The latter requires each hypothesis/theory to be falsifiable. I.e. when presenting a theory, you must say what data, if obtained, will disprove it. However, scientists tend to cling to their pet theory and, when confronted by contradicting facts, modify it to make it compatible to the facts. In some cases this is relevant, but more often such supports just prolong the agony of an entirely wrong theory, sometimes up to 40-50 years.
In its simplest form, the mercury-autism theory postulates higher mercury burden in autistic children. The measured mercury concentration in autistics has three variants - to be (a) higher, (b) the same and (c) lower than in controls. So results (b) or (c), if obtained, contradict the theory. But you see that when (c) is obtained, Dr. Wagnitz says that autistics don't excrete mercury efficiently, and when (b) is obtained, he says that the researcher obtaining (b) isn't a toxicologist and has done a mess of it all. So Wagnitz supports a "theory" that cannot be disproved and hence is no scientific theory at all; it's a cult. BTW Kern et al. have measured mercury in hair - the method Dr. Wagnitz finds wrong; but he doesn't call them incompetent, because they don't challenge his pet theory, even though their results do.
In conclusion, I'd like to ask Dr. Wagnitz two more questions:
(1) Could you please tell us what empirical results, if obtained, will make you admit that the mercury-autism theory is wrong?
(2) How many years must pass after removal of mercury from vaccines so that you stop blaming mercury in vaccines for (the non-diminishing cases of) autism?
Sorry for the long comment, but as one of the few readers who feel at home at the PubMed site, I felt obliged to do the work for the others who don't. And I blame Dr. Wagnitz for making me waste my time, among other sins.
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