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Thimerosal. Again.

Yet another study has shown no link between the former vaccine additive thimerosal and neurological problems in children. This one evaluated over a thousand seven-to-ten year olds for a long list of outcomes, and came up negative. No strong correlations were found, and the weak ones seemed to spread out evenly among positive and negative consequences.
This is just the kind of data that researchers are used to seeing. Most experiments don’t work, and most attempts to find correlations come up empty. The leftovers are a pile of weak, unconvincing traces, all pointing in different directions while not reaching statistical significance. For a study like this one, though, this is a good answer. The question is “Does thimerosal exposure show any connection to any of these forty-two neurological symptoms?”, and the answer is “No. Not as far as we can see, and we looked very hard indeed.”
And this isn’t the first study to find the same sorts of results. The fact that reports of autism do not appear to decrease after thimerosal is removed from circulation should be enough on the face of it, but there’s the problem. To the committed believers, those data are flawed. And these latest data are flawed. All the data that do not confirm that thimerosal is a cause of autism are flawed. Now, if this latest study had shown the ghost of statistical significance, well, that would no doubt be different. But it didn’t, and that means that there’s something wrong with it.
The director of SafeMinds, a group of true thimerosal believers if ever there was, actually was on the consulting board of this latest study. But she withdrew her name from the final document. The CDC is conducting a large thimerosal-and-autism study whose results should come out next year. Here’s a prediction for you: if that one fails to show a connection, and I have every expectation that it’ll fail to show one, SafeMinds will not accept the results. Anyone care to bet against that?
As a scientist, I’ve had to take a lot of good, compelling ideas of mine and toss them into the trash when the data failed to support them. Not everything works, and not everything that looks as if it makes sense really does. It’s getting to the point with the autism/thimerosal hypothesis- has, in fact, gotten to the point quite some time ago – that the data have failed to support it. If you disagree, and I know from my e-mail that some readers will, then ask yourself what data would suffice to make you abandon your belief? If you can’t think of any, you have moved beyond medicine and beyond science, and I’ll not follow you.

26 comments on “Thimerosal. Again.”

  1. isles says:

    Exactly. And I have started to fault CDC for not figuring out how this game works. Every time they say “we’re still studying thimerosal,” they reinforce to well-meaning parents the idea that vaccines might be more dangerous than doctors say they are; every time there’s a new study showing thimerosal is safe, it’s an opportunity for the antivaxers to grab the mike, slam the study on whatever ludicrous grounds they can think of, and repeat their message.
    I’m not saying they should halt the studies currently underway (two of them, I think), but if they do any more than that, they’re not just wasting money, they’re harming kids, not helping them.

  2. I posted a deliberately provocative piece on vaccination and statistics on Sciencebase recently, in which I put a risk assessment argument forward. It got a lot of my readers very hot under the collar. One of the commenters who agreed with my analysis also raised the thimerosol issue repeatedly, was shot down, and jumped again with a new response. He’s a chemist and he’s convinced there is a toxic issue to address.
    Personally, I don’t believe the MMR vaccine has anything to do with autism, but there risks associated with multipe and even vaccination. Speaking anecdotally, I one person who endured a damaged retina very soon after receiving a multiple vaccine shot for an emergency trip to the tropics and another who developed Guillain-Barre syndrome six weeks after their flu jab.
    Such reports do not make a double-blind, placebo controlled clinical study, of course, but they make you think…

  3. Morten says:

    AFAIR autistic children are born with decreased brain weight but don’t show any outward signs of being autistic until a certain age.
    But I think I can understand how parents might get slightly traumatized by their children’s vaccinations – a guy sticks a big needle in their kid, making it cry. And then not so long after another guy tells them that their child has autism. Even for natural skeptics it would be hard not to suspect a connection.
    Actually the thimerosal case would make for an excellent case to teach what false correlation (is that what it is officially called?) and confirmation bias is. But I can’t really imagine any schools teaching scientific reasoning so abstractly…

  4. Zak says:

    Give it up, Derek. We know that you and all your allies in big pharma want to damage our kids while making your own even smarter, all the while holding back your miracle cancer drugs for yourselves.

  5. TW Andrews says:

    Speaking of “good, compelling ideas,” you’ve had, is there any update on the research you were finishing up just before leaving the Wonder Drug Factory?

  6. qetzal says:

    TW Andrews beat me to it, but I had the same question. I’m sure a bunch of us would love an update, if you’re free to give one.
    P.S. I think you have one too many “nots” in the following:

    All the data that do not confirm that thimerosal is not a cause of autism are flawed.

  7. A bad day for antivaccinationists: Yet another study fails to support an association between vaccines and neurodevelopmental disorders

    I’m almost beginning to feel sorry for the mercury militia. Think about it. They’ve been claiming for the past several years that the mercury in the thimerosal used as a preservative in childhood vaccines is a cause of autism. If…

  8. Still Scared of Dinosaurs says:

    Sounds to me like SafeMinds should be renamed MindSafes because their minds only open when the right combination (i.e., data that support their viewpoint) are entered.
    And while I’m guessing Zak was posting with tongue in cheek he reminded me of a colleague who said that a parent of two autistic children abruptly stopped talking to her at a party when she said she worked at a biopharma company. She asked another person what was up and was told that this person blamed everyone in the industry for his bad luck.

  9. Jonathan says:

    Oh man. Countdown until the nutjobs arrive in 5,4,3…
    If there’s one thing I’ve found out writing about science, it’s that writing about autism draws the wackos out of the woodwork like nothing else.

  10. English chemist says:

    Here the other side of the pond there has also been a long-running shouting match over the supposed link of the MMR vaccine to autism. It seems more and more that the scientific evidence gets ignored in the media in favour of the better story (i.e. DOCTORS ARE KILLING OUR CHILDREN…)
    A rare example redressing the balance in favour actual facts is Ben Goldacre’s column in the Guardian:

  11. Hap says:

    Don’r ask testable questions if you aren’t prepared to deal with the answers – or, better, don’t make testable claims if you can’t deal with the criticism when they are found to hold no water. The problems with alternative medicine, vaccine claims, etc., can be ascribed to their inability or unwillingness to follow their ideas to their logical conclusions, or to the willingness of some of their practitioners to sacrifice the welfare of others for their own well-being.

  12. curiousGeorge says:

    What if both sides are correct — thimerosal is quickly execreted in healthy children, but those genetically predisposed to autism are unable to efficiently excrete the mercury? This in turn leads to CNS damage and the first manifestions of autism.

  13. MTK says:

    Thimersol hasn’t been used in vaccines in the US for sometime now, and yet autism rates have not declined. It’s time to spend the limited resources on a different hypothesis. If Safeminds were smart, they would start pushing for that rather than stubbornly
    beating what looks like a dead horse.

  14. Morten says:

    Don’t get wrong #2 – weird things happen with vaccines. Personally I wouldn’t get a flu shot unless I thought the flu could kill me or cause permanent damage.

  15. bootsy says:

    MTK (#12) has it right. The anti-vaccine crusade is now actively promoting the waste of time and money that could be used to find the real cause of the alarming increase of autism.
    I do believe there is a real problem, but there’s a huge amount of effort being wasted disproving this vaccine hypothesis over and over again.
    Vaccines do have risks, but what doesn’t? In the history of public health, there have been few things as effective as vaccines. It boggles my mind that people want to undo that because of (repeatedly) disproven connection to autism.

  16. Chris Croy says:

    What if both sides are correct
    No, then ONE side would be correct. The side of rationality and science says, “There is no connection between thimerosal and autism”. It doesn’t matter if the reason thimerosal makes people autistic is because they can’t secrete it or because mercury lures aliens to children who take them up into their space ship and mess with their brains. If there was a connection, then reducing or eliminating it from vaccines would cause a drop in the prevalence of autism. Since there is no connection, we can safely rule out vaccines and their ingredients as causes.
    the real cause of the alarming increase of autism.
    Imagine for a moment it’s 1950 something and you just got home from Korea. You married your girl, settled down, then fell through a wormhole. It’s now 2007. You walk down the street and see – WHOA! TWO MEN KISSING? After executing them in a biblical manner, you continue down the street, minding your own business when – QUEERS AT 12 O’CLOCK! You’ve no idea what’s going on, but there’s one question on your mind: What made all of these people gay?
    The answer is that they were always there and always gay, just hiding in the closet. It’s the same with autism. We have an epidemic alright: An epidemic of awareness. Whereas before a child that didn’t talk until they were four would have just been a funny kid, now their parents take them to a neurologist and get them treatment. People understand that autism doesn’t necessarily mean you go to an institution or need to be drugged up to your eyeballs. It might just mean you have a collection of odd neurological symptoms that add up to you not playing well with others.

  17. isles says:

    Chris (#15) – awesome comment. Hope you don’t mind that I’m going to use the gay analogy in the future.

  18. Able Linkin says:

    So thimersol is related to homoperversity? That is a compelling hypothesis.

  19. curiousGeorge says:

    Chris Croy –
    The prevalence of autism is very low (on the order of 1/1000. Therefore, 1047 subjects is insufficent to measure a differential response to mercury between healthy and autistic children.
    If the differential hyphothesis I propsed is correct then both sides are correct: Mercury does not cause autism yet there is a correlation between mercury exposure and first onset of symptoms.

  20. John Fryer says:

    I’ll not follow you.
    Are you a scientist when you say this or a politician?
    I have studied thousands of deaths from something called SIDS.
    How many of these ever had one toxic mercury level check. None.
    Science works on facts not: ‘Thimerosal is fine trust me I am a doctor.’
    John Fryer MSc BSc Advanced Analtyical Chemist

  21. John Fryer says:

    Hi Chris 15
    You make 2 comments one I agree with and one is wrong.
    New York State in 2007 wants thimerosal out with legal sanctions for non compliance. Why waste money on a dead issue?
    Many vaccines still contain mercury and this is typical obfuscation when people repeatedly say its gone.
    Mercury is out when its out and if there’s no ban there’s no way you can accept any claim otherwise unless checked by analysis or by specific comments made eg by mattress makers.
    This product contains no arsenic, antimony and NO PHOSPHORUS.
    And this goes back to a different story which partly explains all those gays today.
    John Fryer Chemist

  22. Mitosis says:

    Everyone (esp. lawyers) keep talking about mercury and linking it to Big Pharma yet they fail to talk about lead and what damage it causes to children.
    We are seeing lead found in more products and in the environment.
    There is also a genetic link to autism but then parents can’t sue themselves …

  23. John Fryer says:

    Hi English Chemist
    I feel I could almost be writing to myself but somewhere the facts have got changed.
    Andrew Wakefield may yet be proved right.
    The Denmark issue is accepted as correct by all sides.
    But if you look at the rise of autism in Danish children it appears that it originated in 1987. What happened in Denmark in 1987? What could have caused zero cases of autism to rise to epidemic proportions in 6 years?
    Well one thing is for sure Denmark introduced its National MMR scheme in 1987.
    For me and for Andrew Wakefield MMR has some answers to give us.
    My only claim to fame is that I came up with MMR causing autism more than ten years later than Andrew.
    Do I still qualify for any brownie points?
    John Fryer MSc BSc Chemist

  24. john huffstickler says:

    Well, I do read newspapers, and a CDC topkick recently admitted to Congress that the US-sourced figures widely-quoted for non-toxicity are epidemiologically useless. She did not explain why the US Govt continues to cite those figures on various FAQ’s and in Press handouts.

  25. bfg says:

    Theory: Vaccinations are the primary cause of food allergies. Infant formula, infant vitamins, and antibiotics that contain peanut products directly or indirectly may be secondary causes.
    BACKGROUND: This study began as a “wild idea” that vaccinations or medicine could be causing peanut allergy. It soon turned into a horrible realization. A very small amount of food proteins from many sources are considered inert ingredients that fall under trade secret protection and are not on the vaccine inserts. Various studies have shown that injecting an animal with protein is one method of inducing an allergy. Every study done of food allergy that could be located does not disprove this theory. There was a study done on Indonesian and Thai children that has been frequently quoted as saying that there are no peanut allergies in Thailand or Singapore in spite of the high consumption of peanuts. Evidence was presented that Singapore has a major problem with peanut allergy. The study itself says that many children reacted to peanuts in a skin prick test and that it eliminated a number of children from the study. The “hygiene theory” was examined and found to have no merit. Evidence of a long list of food protein that can be used in vaccine production has been found in various patents on-line. The increased childhood vaccination schedule coincides with the increase in food allergies in industrialized nations. The lower incidence of food allergies in less industrialized nations also coincides with a lower vaccination rate. The lower incidence of food allergies in the Hispanic population of the United States also coincides with a lower vaccination rate. The evidence of food allergy in animals has only been found in vaccinated animals. Evidence of ingredients that can be one of the patented adjuvants with various food oils has been presented. Evidence that “pharmacy grade” peanut oil still contains peanut protein has been presented. Package inserts have been examined and found to have ingredients that do not disclose its actual composition. EVERY SINGLE FOOD ALLERGY THAT I HAVE FOUND, I HAVE ALSO FOUND THAT FOOD LISTED AS AN INGREDIENT IN A VACCINE OR MEDICAL PRODUCT.
    Many of these pages were copied from my blog. The blog grew too big and was too hard to follow. The links listed below link to the article in my blog. Use the buttons to the right to go to the article on this website. If you’d like to leave a comment, you can do so on the blog or you can e-mail me by way of the contact page- bfg
    1. Vaccines are given to create an immune response from the body. It only makes sense that the body treats anything in the vaccine as an invader that needs to have an antibody created to combat it. That is why we give vaccines. But if the vaccine has a trace of food in it such as egg or peanut, it only makes sense that the vaccine can cause a food allergy.
    2. Peanut oil is used in vaccines in adjuvants or as a vaccine carrier. The ingredients of adjuvants or vaccine carriers are not listed individually on the package insert. So the physician would have no way of knowing that there was peanut oil in the vaccine. The ingredients of adjuvants is considered a “trade secret” and has the protection of many governments not to be revealed.
    3. Peanut allergy decreases in populations that have decreased percentage of vaccinated children. There are a number of studies that link vaccinations to allergies.
    4. Peanut allergy is almost unknown in Israel. The population eats lots of peanuts. Israel produces sesame oil. Israel manufactures its own vaccines. Sesame is a major allergy there. Hypothesis: Sesame oil is used instead of peanut oil in the vaccines used in Israel.
    5. Study that is frequently cited saying that Indonesia and Thailand people do not suffer from peanut allergies was erroneous. Many children in the study reacted to peanuts in the skin prick test. The study relied on parents of report food reactions. I found a Thai parent quoted on the Internet saying that her child had a peanut allergy. I also found a physician from Singapore stating that peanut allergy is a major problem there.
    6. The “hygiene” theory points out that there is less food allergy in underdeveloped countries. They speculated that the people and environment is less clean so it is the early exposure to bacteria, etc. that protects against allergies. However, children as young as 8 months have been diagnosed with peanut allergy and it is only since 1990 that peanut allergies have become a huge problem. The populations in the underdeveloped countries are also not as compliant with childhood vaccinations which would account for less peanut allergy.
    7. The United States and China are major producers of peanut oil and vaccinations. There are many patents for products used in vaccines that contain peanut oil.
    8. The secondary causes of peanut allergy are due to young children having a “leaky gut”, immature digestive system. Introducing foods too soon can lead to allergies. Medicines given with traces of peanut protein could lead to an allergy. Also antibiotics kill off good bacteria as well as bad and can lead to an overgrowth of yeast which can cause food allergy type problems. I don’t know if any infant formula in the United States contains peanut oil. One website said it was more of a problem in Europe.
    9. Our vaccinated animals are getting food allergies Dogs are allergic to peanuts. Searching the Internet – I found a wild elephant allergic to wheat; the elephant had been immunized. (Wheat germ oil is used as a carrier of vaccines. Wheat protein is used to manufacture vaccines/medicines.)
    10. The statistics for allergies is appalling!! The allergy epidemic increased with every new mandate for more childhood immunizations.
    11. How pure can we make peanut oil? I assume it is highly refined but it only would take a teeny weeny bit of peanut protein in a vaccine to create a problem. That is, of course, assuming that it is ONLY the peanut protein that causes the allergy. Using my “guessing” math, only 1 shot out of 1680 would need to be contaminated to create a peanut allergy in 1 in 70 people in Great Britain.
    12. Vaccine adjuvants/ vaccine carriers contain many other oils/ingredients. These other ingredients could account for allergies to other foods. Fish oil is used. Shellfish can be mixed in with the fish by-products which are used to make fish oil. Wheat germ oil, corn oil, soy oil are used. Milk and eggs are also used in the production of vaccines. I expect that the oils are mixed in the vaccines so that you might get a vaccine with peanut oil and soy oil in it or any number of other oils.
    I keep looking but so far, I have been unable to DISPROVE my theory. And perhaps that is because VACCINES ARE A MAJOR CAUSE OF FOOD ALLERGIES!!

  26. hguhf says:

    When Someone said your blog post, Hopefully it doesnt disappoint me around this. I am talking about, I know it was my option to read, on the other hand actually thought youd have something interesting to state. All I hear is a bunch of whining about something you could fix if you werent too busy seeking attention.

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