David Kirby’s Causation Trail

22 Feb

In a truly fascinating exchange on the Evidence of Harm Yahoo Group, David Kirby has revealed:

…the studies which, when taken together, suggest a plausible biological mechanism for mercury exposure as a contributing factor to regressive autism

The exchange came about as a ‘renegade’ poster to that group started laying down a smidgen of fact regarding the state of the science that props up the thiomersal hypothesis. S/he is not a popular bunny on that group.

The exchange led group big cheese Lenny Schafer to state:

It seems that junk science is in the eye of the beholder. It will probably take an impartial jury in a court of law to substantially settle if there is enough evidence of harm to implicate thimerosal and or vaccines in autism.

Seems like Lenny hasn’t been keeping up with the news in that regard.

Anyway, back to David Kirby. Hot on the heels of his amusing further goalpost shifting (somehow the non-decrease in autism numbers which, in 2005 and 2006 would be a grave blow to the thiomersal hypothesis are now suddenly nothing to trouble this teflon coated hypothesis) comes this – David Kirby’s statement on the existing studies which support mercury exposure (what? Not ‘MERCURY _IN VACCINES_ AND THE AUTISM EPIDEMIC: A MEDICAL CONTROVERSY’ David? Just any old mercury now is it? Bless you for exposing the courage of your convictions.)

So which studies float David’s boat? This is his list:

Richard Deth, Northeastern U;
Martha Herbert, Harvard U;
Jill James, Univ of Arkansas;
Thomas Burbacher, Univ of Washington;
Diana Vargas, Johns Hopkins;
Isaac Pessah, UC Davis;
Mady Hornig, Columbia U;
Mark Noble, Univ of Rochester.

Eight people, eight studies. Thise is the ‘science’ that David thinks suggest a plausible mechanism for mercury being a contributing factor for regressive autism.

As an amusing aside, don’t you love (and appreciate!) how careful David is becoming with his choice of words these days? No more of this ‘thiomersal causes autism’ stuff for him! Now its’mercury’ (not ‘MERCURY _IN VACCINES_ AND THE AUTISM EPIDEMIC: A MEDICAL CONTROVERSY’) and instead of ‘causing’ we have ‘contributing factor’ and instead of autism we now have ‘regressive autism’. best of all we have ‘suggest’ instead of MERCURY IN VACCINES AND THE AUTISM EPIDEMIC. Bless him, all the blog reading he’s been doing from the skeptical folks is finally paying off.

So, lets turn our attention to these studies of David’s. First of all we should note that the Mark Noble cite is a red herring (you lose skeptic points for that David) as, if I’m not mistaken, this study is a) a pilot study and b) not as yet underway. Certainly none of the other ten studies PubMed attributes to Noble, M. appear to discuss autism. Naughty naughty.

Richard Deth

Deth’s paper, if I may quote myself, can be summed up thusly:The basic gist of the Deth paper is that various toxins, including thimerosal, affect methionine synthase activity (a process that helps in building proteins) and that this can adversely affect children. In short, the Deth paper alleges that thimerosal causes methionine synthase dysfunction (MSD).

There are several issues with this as they relate to autism. Firstly, MSD and autism do not resemble each other. Symptoms of MSD are: Anemia, moderate to severe developmental delay, lethargy, anorexia, and homocystinuria (mental retardation, dislocation of the crystalline lens of the eye, sparse blond hair, and cardiovascular and skeletal deformities). Further issues:

1) There is no active transport mechanism into the central nervous system currently known for ethylmercury (thimerosal) whereas there is an known and active transport mechanism for methylmercury.
2) Because its half-life is much longer, methylmercury is more likely to accumulate than ethylmercury, causing higher levels of mercury in the blood.
3) Exposing cells in vitro to ethylmercury eliminates the most important difference between those two forms of mercury, and ignores the fact that ethylmercury is unlikely to enter the central nervous system at concentrations likely to be harmful.
4) The authors chose to use a cell line derived from a metastatic peripheral nervous system tumor to make predictions about developing healthy cells of the central nervous system. If the authors were interested in making claims about the developing central nervous system they should use cells derived from there.
5) The authors make statements in their introduction about developmental disorders such as fetal alcohol syndrome, Rhett’s syndrome, or Fragile-X syndrome, they fail to consider the fact that all of these diseases have their origins in the developing embryo and fetus, not postnatally.
6) The authors’ reference a study that evaluated the causal association between thimerosal and vaccines using the Vaccine Adverse Events Reporting System (VAERS). Remember how good VAERS is?

Bart Cubbins produced a video detailing similar points.

Martha Herbert and Dianne Vargas

These two papers independeintly of each other indicated a role for neuroinflammation in autism (<a href="http://www.generationrescue.org/pdf/herbert.pdf&quot; rel="nofollow"Herbert here and Vargas here but they differ slightly. The Vargas paper states:

neuroinflammatory process appears to be associated with an ongoing and chronic mechanism of CNS dysfunction

and leaves it at that. Herbert specualtes with no basis regarding the fact that metals might play a part in the neuroinflammation. She has no basis for these speculations and it surprises me that they’re in a paper published in such a good journal.

Jill James

Jill James’s studies revolve around glutathione. Glutathione, amongst other things, removes merucry from the human body. James’ studies purport to show that autistic people are deficient in Glutathione and thus when they get mercury they can’t excrete it in the same way non-autistic people do.

However, they don’t. James tried to show that the two types of Glutathione in the body (what she called Active and Inactive) were about 31% (Active) and 33% (Inactive) less in autistic kids than non-autistic kids. However, it should be noted that these are not two differing forms of Glutathione but instead two states of one thing which have a relationship to each other – when one goes up, the other goes down. As Not Mercury states:

Decreased synthetic capability is one possible explanation but this would probably result in a significant deficit of total glutathione not an imbalance between the two oxidation states. _If James found any evidence of impaired glutathione synthesis in this small group of children it wasn’t included in any of her published work_. It doesn’t sound like the children were suffering from a glutathione deficiency as much as an increased oxidative burden greater than the capacity to recycle and glutathione and maintain full oxidative defense capacity.

No deficiency in Glutathione. But Not Mercury takes it a step further:

let’s suppose children with autism had significantly lower levels of glutathione. Would it render them unable to detoxify thimerosal from vaccines? Probably not.

The average human carries about 6milligrams mercury, even if James’ figures were accurate (which they are clearly not) or represent what she claims they do (which they clearly don’t) then the human body would still have several million times more glutathione than needed to excrete the suspect mercury. As Not Mercury says:

A person so severely deficient in glutathione they would be unable to detoxify 250 micrograms of mercury (upper limit of thiomersal in vaccines 5 years ago) probably wouldn’t survive long enough to be vaccinated in the first place. Every breath of air would expose them to lethal levels of ozone, pollutants and other oxidants.

Please read all of Not Mercury’s piece. It’s an eye opener.

Thomas Burbacher

This paper reached one conclusion.

The key findings of the current study are the differences in the disposition kinetics and demethylation rates of thimerosal and MeHg. Consequently, MeHg is not a suitable reference for risk assessment from exposure to thimerosal derived Hg. Knowledge of the biotransformation of thimerosal, the chemical identity of the Hg-containing species in the blood and brain, and the neurotoxic potential of intact thimerosal and its various biotransformation products, including ethylmercury are urgently needed to afford a meaningful interpretation of the potential developmental effects of immunization with thimerosal-containing vaccines in newborns and infants. This information is critical if we are to respond to public concerns regarding the safety of childhood immunizations

In other words, Burbacher blood vs brain is not a valid comparison and that methHG vs ethHG is not valid either. He then goes on to state that more research is needed into what the toxic effects of thimerosal might be. He states that mercury from vaccines doesn’t accumulate as much in blood as it does in the brain and thusly, using blood levels of mercury to represent brain levels of mercury is innacurate.

It was also presented that this paper connected the dots between thiomersal and neuroinflammation (see Herbert and Vargas) but this is a false representation and not claimed or even insinuated by Burbacher.

Two more issues arose from this paper. Firstly, when the Burbacher team performed the extraction of mercury from the blood or brain matter, they failed to introduce controls to ensure that the thimerosal was not degraded in any way as a result of the extraction process. This means they had to basically assume from the resultant possibly contaminated material how much was attributable to methylmercury and how much to thimerosal (ethylmercury). Secondly, Burbacher used thimerosal free vaccines and added pure thimerosal. It is difficult to know how this fresh preparation compares with vaccine formulas when thimerosal is part of the manufacturing process and may have suffered some degradation to inorganic Hg in the vials before administration.

Issac Pessah

The Pessah paper related how the study team found that thiomersal administered to mice caused “dendritic cells” damage. Specifically:

the thimerosal disrupted the normal biological signals that take place in cells, Pessah said. At lower concentrations, the signal disruption caused an inflammatory response; at higher concentrations it caused cell death.

So the position here is that thimerosal has a negative effect on the immune system. Lots of parents think autism is immune-system related. However, this study is a) unreplicated (as far as I know) and b) we may be overestmating the real world effect. Here’s Autism Diva talking about hearing Pessah on Autism One radio.

But the really weird thing is how he described how long the effect would last when the dendritic cells came into contact with mercury. If Autism Diva understood him correctly, lets say a kid gets injected with a vaccine containing thimerosal and the dendritic cells that come into contact with the thimerosal. This is not necessarily all the dendritic cells–some of them, and the DCs are affected by the thimerosal, depending on how much thimerosal they come into contact with. And this effect lasts…. years and years? Is that what he said? No.

Was it months and months? Is that what he said? Maybe it was days and days? Hours and hours? No, actually, what he said, if Autism Diva heard him correctly, was “minutes and minutes.”

So, we know that if you take dendritic cells of a particular kind out of a mouse, and grow them in a glass dish and dump a weak solution of thimerosal on them, they freak out or get a little weird and either way can’t do their job normally, and this effect lasts for,

(gasp)

minutes and minutes.

And speaking of Autism Diva we come around to:

Mady Hornig

Briefly, Mady Horning conducted a study wherein she claimed to have developed a mouse model for autism which she then used to test how the model responded to the introduction of thiomersal. According to Hornig, the study showed that:

1. The mice they used are a good model for autistic people
2. The ‘vaccine’ schedule they used successfully mimicks childhood immunization programs
3. That the outcomes from Auto-immune disease sensitive mice were consistent with autism
4. That this indicates a genetically influenced sensitivity to thimerosal in autistic people

Autism Diva took this study apart when she pointed out that:

Did Dr. Hornig and colleagues find these features [diagnostic criteria for autism] in the ‘SJL Thim” mice?’ No.

Prometheus also had reservations about the design of the study:

So, the human experiences a maximum blood level of 1.63 (arbitrary units) and the mouse – since it is being dosed at a smaller fraction of its half-life – sees a maximum blood level of 2.61. In short, the mouse gets to a blood level 60% higher than the human……I found myself wondering, “Why didn’t they use the 50th percentile (50% weigh more than this weight, 50% weigh less – sort of an ‘average weight’)?” I have no answer – but I have an idea. By using the 10th percentile, they were able to give the baby mice an even bigger dose of mercury……So, by using the 10th percentile weights, the authors were able to give the mice about 15% more thimerosal. This goes nicely with the dosing schedule to significantly raise the dose the mice receive.

One of the big talking points from this study was reported by David Kirby in Evidence of Harm:

… putting up a photo of two mice. “He has groomed through the skull, and eventually destroys his partner,” Hornig said. Every parent of an autistic kid in the room could be seen grimacing in dark recognition of such destructive behavior.”(page 312)

Uh-huh, or maybe they were just grimacing as its not nice looking at mice chewing through the skulls of other mice?

Anyway, hyperbole aside, why did Hornig choose those particular mice? Here’s what else Autism Diva found out.

Why did Hornig pick the SJL/J mice in particular?….Besides being an “autoimmune disease-sensitive” breed what else is known about the SJL/J mice?

Good question. Diva found the answer highly revealing:

Behavior
1. High spontaneous fighting….
2. Severe fighting among males housed together, beginning at about 8 weeks.
3. Most males will be killed by 4-5 months unless caged separately….

Diva also found a separate source that showed that:

…some breeds do a kind of agressive grooming of other mice called, “barbering”

So, it seems that Hornig sourced a set of mice known to be aggressive, she then systematically overdosed them and then reported the fact that this aggression was indicative of autism. Right.

Wrapping It Up

A study that hasn’t yet been done. A study that alleges something it can’t back up. A study with no data and empty conclusions. Two studies that have nothing discernable to do with heavy metals. A study that shows ethylmercury and methylmercury are not comparable. A study that damages cells taken from a mouse for the span of minutes and a study that purposefully overdosed mice known to be aggressive.

Lets remind ourselves of the Judge;s opinion of this same body of science when it was presented by Dr Geier in the RhoGAM hearings as support for the view that thiomersal causes autism:

…the Court notes that, in fact, a literature review can be an appropriate part of a method of determining general causation. However, a literature review must still be performed appropriately. As revealed by his testimony at the Daubert hearing, Dr. Geier, however, relied upon a number of disparate and unconnected studies, including the findings of Dr. Haley and Dr. Lucier, to reach a piecemeal conclusion with respect to general causation…..However, upon being subjected to extensive cross examination, much of Dr. Geier’s analysis, based upon his collective review of a motley assortment of diverse literature, proved, in the Court’s view, to be overstated.

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31 Responses to “David Kirby’s Causation Trail”

  1. anonimouse February 22, 2007 at 17:26 #

    These studies don’t even interrelate very well, and in some cases come pretty close (if not outright) contradict each other.

    And these studies would be far more useful if there was some kind of broad epidemiological evidence that thimerosal in vaccines (or mercury in general) could be linked to autism. (or even regressive autism) To date, no such link exists, nor is there any study that shows the chelating or removing mercury from the body makes a lick of difference when it comes to an autistic child or adult.

    Now, I know very soon this little blog will be overrun with anecdotes screaming about how little Johnny was a mute, self-injurious poop-smearer until he took DMSA and is now indistinguishable from his peers. They’ll claim that they had thousands of dollars of test done that prove little Johnny was poisoned and how dare we say otherwise.

  2. isles February 22, 2007 at 19:08 #

    The Institute of Medicine had a lot to say about this kind of “evidence.” Most pertinently:
    “[A]n assessment of the biological plausibility of an association demonstrated by epidemiological analysis is meant to ensure that such an association is consistent with current biological knowledge. Evidence regarding biological plausibility, however, can never prove causality.”
    (Vaccines and Autism, 2004, at 27-28)

    In small words: You must have epi data before bio is even relevant.

    Oh, but the IOM is just a bunch of pharma shills, right?

  3. Joseph February 22, 2007 at 19:36 #

    Right, if you don’t have epidemiology, you can speculate about possible biological mechanisms all you want, but that doesn’t demonstrate causality.

    And as Tom (the “renegade” list member) pointed out, the only epidemiology purporting to link thimerosal with autism comes from Geier & Geier, which by itself puts the epi in doubt. Further, we all know what that epi looks like.

  4. Bartholomew Cubbins February 22, 2007 at 21:07 #

    If one wants to prove something regarding complex biological phenomena, either a single killer experiment must be performed — one that is unambiguous and replicable — or many solid pieces of evidence can be stacked together to form a coherent story. The problem with the latter is that each individual piece of evidence (experiment, project, whatever) must pass the rigors of the scientific process and peer review in order to be deemed believable. There isn’t a single paper listed above that was published in a great journal. The authors aren’t stupid, if their papers were solid enough and important enough, they would have been submitted to and reviewed at Cell, Science, or Nature.

    As it stands, the autism=mercury poisoning game of Jenga is being played with marbles: pieces that don’t fit and won’t stack up into a real story.

    It also amazes me that some adult besides OJ Simpson can actually place more faith in the legal system than the scientific process. What a truly bizarre and frightening concept.

  5. Ms. Clark February 22, 2007 at 21:43 #

    Isles wrote:
    “In small words: You must have epi data before bio is even relevant.”

    That’s where the smoke and mirrors comes in. Thimerosal is soooo toxic that it could create an autism epidemic where there was none before… meaning that the majority of children who were diagnosed as autistic of the “epidemic victims” i.e. most of the 1 in 166 children in the U.S. (never mind the rest of the world) were made autistic by vaccines containing thimerosal. That was the main claim that got all this into the news (a generation of children destroyed by thimerosal…).

    But they can’t show that taking thimerosal out (or putting it in even) makes any difference from the broad view of epidemiology, so they respond,…. but epidemiology can’t prove that 1 in 10,000 (or 1 in 100,000) a normal child that is made autistic by thimerosal (don’t forget the vaccines cause regression with the regression following the vaccination by hours, days, weeks or months) . So really it’s just THEIR particular children who were made autistic by vaccines, the ones who claim their child regressed following vaccination and has DDI lab reports “proving” that Johnny getting that 87 mcg in a vaccine at age 18 months is why he’s dumping 12 or 120 or 1200 mcg per day 3 to 5 years later (post chelation).

    Lest not forget how ridiculout DDI lab reports are, terrifying parents with Hg, Aresenic, Bismuth, Aluminum, Lead, and Antimony levels in the RED ZONE, with comparisons of provoked urine samples to non-provoked comparitors (and profiting nicely, too!)

    The thing is that the mercury militia (and Kirby) couldn’t get national attention if they said that really it’s only their children who were affected, not the majority of autistic children (who don’t regress or if they regress, don’t regress immediately following a vaccine).

    Never mind that there never was an epidemic caused by ANYTHING, much less helpful vaccines.

    There are problems with all those published studies that Kirby cited, BIG fat problems. Like Burbacher’s thimerosal dosed monkeys didn’t act any different, didn’t act brain damaged at all.

    At least Amaral’s monkey’s act differently (if not autistic).

    If Hornig knew that her data was compelling she would not have had to resort to the disgusting horror show video that she’s been hauling around with her since her trip to the IOM (shortly before the publication of the stupid Rain Mouse paper). How obvious is that? Her behavior is so out of the realm of what real scientists do it’s really stunning. Whatever happened to her “Go for the Gold” Rain Mouse study. She was supposed to overdose SJL-J mice again and then dose them wtih toxic (heavy metal) gold salts in order to chelate them and cure them of their “autism.” She should have chelated her little killer mousies while she still had them, anyway, she could have reversed their natural killer instincts, right?

    Amaral submitted his recent monkey paper to Science and it was rejected so he submitted it to Biological Psychiatry or something.
    Should be interesting, but apparently it’s not so stunning that Science would include it in their journal.

  6. notmercury February 22, 2007 at 22:50 #

    Nice job pulling this all together Kev. Of course DK is welcome to debate any of this ‘science’ here or anywhere else but we know he has a hard time sticking to topic during a debate.

    I’d also like to point out that Martha Herbert hasn’t observed anything like neuroinflammation and merely included the Vargas findings in her review paper.

    Tom, whoever you are, way to go.

  7. Ms. Clark February 23, 2007 at 02:30 #

    The renegade poster appeared first with just the handle “rhodopsin1.”

    Brian Hooker (bizarre man that he is, weren’t the police involved with something he did that was like stalking or making threatening phone calls or something???) was pretty sure that rhodopsin1 was me. So he asked (on the EoHam group). Rhodopsin1 answered his name was Tom, that was not me.

    There were several snotty comments made about me along with a bizarre accusation by Hooker that I had somehow insulted, or exposed his child to some danger, or something. Supposedly whatever I had done was “mean” but he didn’t provide any evidence of it.

    But I have never written anything about his child. If I have, I’d appreciate someone linking to it, because I don’t think I’ve ever known any facts about Brian’s child, much less posted them anywhere.

  8. David N. Andrews M. Ed. (Distinction) February 23, 2007 at 14:05 #

    http://www.davidkirbylies.com/

    Sadly that page does not exist.

    Wish it did.

  9. anonimouse February 23, 2007 at 14:31 #

    That page needs to exist.

    Is the domain available? ;-)

  10. Tom February 23, 2007 at 16:27 #

    I guess this is an informal introduction and apologia. I hope my presence won’t create a flame war on your site and I can understand if you don’t post this. But if you do…

    My name is Tom. I am not purple. I am not Autism Diva—she rocks! Indeed, all you folks on the AutismHub rock!

    I am the father of a bright, sensitive, vulnerable, delightful young boy who was diagnosed in December. Like all children, he has gifts and challenges. Some of his traits just stand out a little more.

    He is not damaged goods. He was not poisoned. He is not a “train wreck”. His soul has not been robbed. I strongly object to anyone portraying him as such. And I can’t imagine telling him these things when he grows older. I worry that this will be one more form of torture directed his way.

    These last two months, my wife and I have sought help and advice not to “cure” him but to look for interventions that will help him navigate his world. What we mostly encountered were parents who told us if we didn’t seek out DAN doctors, test for mercury, chelate and put him on a GFCF diet, we were failing him. We turned to Pub Med and found the literature pretty sparse. Even the most widely used behavioral/cognitive approaches seem to have escaped rigorous evaluation. What I mostly found outside Pub Med was more nonsense about vaccination and cures for autism.

    One name, David Kirby, kept popping up in all of this. I was told his was a book I had to read. It would change our lives.

    I watched the UCSD “debate” and read about as much as I could stomach. My gut became leaky. I read about the Geiers and realized Kirby had based much of the scientific basis for his book on an unaffiliated researcher who works in his suburban home with his untrained, uncredentialed son. Then I saw a video of the two discussing lupron. I was speechless. How could you miss that? It all left me wondering about Kirby’s motivations.

    Anyway, in the midst of all this, 60 minutes airs their early diagnosis segment and throws in a few seconds with Steve Goodman, because you can’t cover autism without talking about mercury. Steve Goodman is brilliant, hardworking and, above all else, no one’s fool. He has no conflicts of interest and was exactly the right person for the IOM committee. Had there been any reason to doubt the epidemiologic evidence, he’d make it known. In the ensuing days, I read all of the character assassinations on the EoH list and could lurk no more.

    I was amazed that David Kirby responded at all much less in the way he did. The truly strange thing is that Kirby has thrown his career in with this motley EoH crew. As Kev clearly showed, the citations were dishonest misreadings of work. (By the way, thanks Kev for taking the time to spell that out.) Moreover, his missive reeked of an egomaniac thinking he could simply intimidate to quiet the opposition. His motivations are clear to me now.

    Kirby is responsible for lending credibility to the lies that vaccines are to be avoided and that children with autism are the victims of mercury. I can understand parents, who lack medical insight, wrongly inferring causation, but Kirby has no excuse. He should renounce the Geiers and portray himself as a victim of their fraud. It would not only rehabilitate his career but seriously elevate it. He could get another book from it. Instead, he buries himself deeper with mercury clouds, glutathione deficiencies, and mischaracterizations of any work that is even remotely related.

    I did not plan on entering a battle with EoH and don’t really want to go round and round with them; it’s pointless. But nothing ventured, nothing gained. And I gained a sense of just who David Kirby is and for that I am grateful.

  11. sploobie February 23, 2007 at 19:46 #

    Camille

    What you wrote was about me (under your pseudonym ghrelin) and not my child. Fortunately, the webmaster at AutismWeb removed the content.

    Brian

  12. sploobie February 23, 2007 at 20:36 #

    You don’t even know me… Why use such inflammatory language?

  13. Ms. Clark February 23, 2007 at 20:58 #

    Mr. Hooker. I don’t remember ever posting any information about you on autismweb.com forum. I think you got me confused with someone else. I remember you trying to make a huge deal out some imagined slight that the moderator erased because it was so bizarre.

    I remember you freaking out because some told you that they knew who “sploobie” was when you showed up using that name on the autismweb.com forum, apparently thinking that no one there would recognize that that is your handle on other groups where you also give your real name. But it wasn’t me, I wasn’t posting there at that time, I was just reading.

    http://autismweb.com/forum/viewtopic.php?t=9242&postdays=0&postorder=asc&start=20&sid=27b7bf7da5cbf8c5377b2491d56f35ce

    Here is where the moderator talks about removing a thread started by you on the topic of how awful I am and some heinous thing I supposedly did in writing about your child??

    http://autismweb.com/forum/viewtopic.php?p=65636#65636

    If you can show me that I have written something awful about you or your child that should have been private or something about you that wasn’t true, we can discuss it here and I’ll apologize if you can show me that I really did something “mean” as you said on the EoHarm list.

    There has been some interesting discussion here on Kev’s blog as I remember, something about you calling a woman at her place of work about something she said about thimerosal, and her feeling a need to call the campus police? Is that right?

  14. onibasuator February 23, 2007 at 21:11 #

    http://onibasu.com/archives/am/136448.html

    http://onibasu.com/archives/am/136637.html

    Kerbob’s comment

    http://onibasu.com/archives/am/136649.html

    This whole thing reminds me of the episode of Seinfeld when George left increasingly aggitated phone messages on the machine of a girl he had just started dating. To quote the character “I was like Mussolini on the balcony.”

  15. isles February 23, 2007 at 21:27 #

    A little bit off topic here: I happened to be thinking today about the frequent claim that infants “have no blood-brain barrier” and are thus especially vulnerable to the administration of mercury. I poked around a little and could find no evidence of this being true. Am I missing something?

    I did happen to come across a mention on eMedicine that calcium EDTA does not cross the blood-brain barrier. And yet this is the chelation agent that the mercury people claim is whisking the mercury out of their children’s brains?

  16. sploobie February 23, 2007 at 21:31 #

    Infants do have a blood brain barrier. I believe that the membranes involved are produced by astrocytes, which are in the developing brain, prior to birth. I don’t believe that EDTA passes the blood brain barrier. Most chelators do not.

  17. isles February 23, 2007 at 22:07 #

    And sooo…the use of chelation is….?

    (Does the chelator wait outside the blood-brain barrier and honk its horn? Does it toss pebbles at the windows to get the mercury to look out and be captivated?)

  18. sploobie February 23, 2007 at 22:08 #

    I’m not a fan of chelation.

  19. isles February 23, 2007 at 22:12 #

    Shhh, don’t let Lenny hear you say that, or he’ll kick you off EOH.

    I’m not a chemist, Brian, so use small words, but how come you attribute autism to thimerosal when it’s methylmercury that is actively transported across the blood-brain barrier?

    A note on the Noble study: I think I’ve seen the study being alluded to, and nowhere does that paper contain the words “ethylmercury” or “thimerosal.” Just methylmercury.

  20. sploobie February 23, 2007 at 22:15 #

    The DSM IV definition of autism has several variants (at a minimum). Thimerosal is only one of a host of issues…

    EtHg eclipsed the BBB in the Burbacher study…

  21. isles February 23, 2007 at 22:30 #

    Yes, but in much smaller amounts than MeHg. I also happened to see a claim today that the average human takes in 4.6 mcg MeHg every day via air, water, etc. Why is thimerosal a big deal compared to this continual mercury assault? Can being delivered into a muscle really endow it with superpowers?

  22. sploobie February 23, 2007 at 22:36 #

    The issue that Burbacher pointed out was the longer half-life of inorganic Hg in thimerosal exposed macaques. The half-life was evidently too long to be determined within the study time period. It eclipsed the half-lives of organic MeHg, inorganic Hg in the methyl group and organic EtHg from thimerosal.

  23. isles February 23, 2007 at 22:53 #

    Which might be enough to raise concerns in cautious people. (Bartholomew Cubbins raised some other criticisms of this study; I don’t remember well enough to restate them. I will stipulate for purposes of this post that thimerosal causes a bit of inorganic mercury to get stuck in the brain.)

    Those cautious people might want to do a study…maybe compare whether people who have been exposed to thimerosal more commonly develop autism or other neurodevelopmental disorders than people who were never exposed to it.

    Is there another way to determine whether it’s actually injurious to have this speck of inorganic mercury resident in the brain? You would think that taking out half a person’s brain would be inconsistent with life – but actually, hemispherectomies are done quite successfully. You would think shooting a laser into the brain would be catastrophic, but it’s actually an elegant way of doing surgery. The point is, even if you assume mercury is resident in the brain, there’s no reason to jump to the conclusion that autism is the result. We have plenty of human subjects on which this question has, in effect, been tested. More thimerosal just doesn’t turn out to make for more autism. Otherwise we’d be seeing much less autism in the population today.

    I don’t imagine you’re going to change your stance, but it’s been oddly nice having this exchange.

  24. sploobie February 23, 2007 at 23:00 #

    Thank you – I agree… It’s great to chat without inflammatory rhetoric.

    In the advent of post-genomic, point-of-care medicine, the best thing to do for any malady is to get a full battery of laboratory tests. It’s too easy on either side of the debate to say what does or doesn’t cause “autism” rather than finding the issues that are pertinent for that particular child or adult.

  25. María Luján February 23, 2007 at 23:10 #

    Hi sploobie and isles
    Are you interested on some comments about Dr Deth and Dr Burbacher manuscripts?
    Please let me know

  26. sploobie February 23, 2007 at 23:13 #

    Sure Maria,

    What is the best way to share them – email?

  27. María Luján February 24, 2007 at 00:10 #

    Yes. Being this Kev´s blog I think e-mail is adequate.
    My e-mail is ferreiramaralujn@yahoo.com.
    Thank you for your interest.

  28. sploobie February 24, 2007 at 02:22 #

    “Mr. Hooker. I don’t remember ever posting any information about you on autismweb.com forum.”

    Ms. Clark,

    If you don’t go by the pseudonym, “Ghrelin” then you didn’t post anything about me that I know of. If indeed that is the case, I sincerely apologize.

    Brian

  29. Prometheus February 24, 2007 at 03:07 #

    One point that needs to be made – not about Kev’s excellent post, but about some of the commentary that swirls around it – is that there is a huge elephant in the room that none of the mercury-causes-autism proponents want to talk about:

    Nobody has yet shown that mercury can cause autism.

    Nope. Nobody.

    They have deflected attention from that point by their assertions that mercury is a known neurotoxin. That is true. It is so well known that the signs and symptoms of mercury poisoning have been well-documented. Strangely, autism or autistic-like traits are not seen in mercury poisoning.

    What are the prominent signs of mercury poisoning, you ask?

    [1] Tremor. This is such a predictable and consistent finding in even early mercury poisoning that it can be used (by examining handwriting samples) to determine when the poisoning began. It is also a key factor in many of the early-detection tests for mercury poisoning.

    [2] Loss of coordination. This isn’t merely being clumsy, but is an inability to perform rapid, repetitive motions. Like flapping and spinning.

    [3] Pressured speech. Talking too much and swerving wildly from one topic to another. Not perseverating on a single topic or a narrow range of topics.

    Many in the mercury-causes-autism “movement” speak and act as if the connection between autism and mercury was a “done deal”, but that could not be any farther from the truth.

    Don’t let them get away with pretending that they have made the connection as they try to weasel away from blaming vaccines and onto blaming “mercury exposure”. Until they can show that mercury can cause autism – at a high dose, low dose or intermediate dose – they haven’t got a leg to stand on.

    Prometheus

  30. Ruth February 24, 2007 at 03:54 #

    If Hg causes autism, Iraq and Japan should have the highest rates. The region of Japan where Minamata Bay is has no higher rate of autism (as defined by their criteria) than any other region in Japan.

  31. anonimouse February 26, 2007 at 14:33 #

    Prometheus,

    This is why armchair pseudo-intellectual posers like the mercury militia should not attempt to publish science or comment on it. The Bernard article was a classic example of picking a few common symptoms from column A and column B and saying “AHA! Mercury poisoning looks like autism!”

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