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Published online 14 July 2008 | Nature 453, 259 (2008) | doi:10.1038/454259a
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Autism study panned by critics
Plan to use chelating agents on children comes under fire.
The leading US government funder of autism research is drawing fire over its proposal to run a randomized clinical trial of a treatment widely viewed by experts to be useless and potentially harmful, but that is broadly used for autism.
Chelation therapy, in which agents such as dimercaptosuccinic acid (DMSA) are used to bind metal ions in the blood so that they can be excreted easily, is an approved treatment for heavy-metal poisoning.
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There are different autisms and different causes of autism. A main cause of non-familial autism is older paternal age, past the age of 31- with increasing risk as a man age. Why doesn't Tom Insel of the NIMH mention this cause of autism and schizophrenia???? http://www.schizophreniaforum.org/for/curr/Malaspina/default.asp
I would have to agree, that such trace levels of Hg detected in autistic patient samples, is not nearly enough to cause toxic effects which would result in neurological damage. However it is important to keep in mind, that there have been significant findings in the last decade, linking metals to such psychological disorders (i.e. autism, schizophrenia, etc.), which were first initiated due to the symptoms displayed by patients suffering from Wilson's Disease. These patients are almost always diagnosed as late-onset schizophrenics, when in fact they are suffering from copper toxicity. There have also been several studies which indicate that a good majority of autistic patients suffer from depleted zinc levels. With this being said, giving said patients chelation therapy could have detrimental effects. I feel that the NIH needs to aggressively pursue researching the link between the metals and psychological disorders based on raw data and facts, and not popular demand from biased sources.
My hypothesis is that a minority of people are more sensitive to metals (particularly mercury) than most and that for these individuals a combination of genes and exposure to metals might be damaging. By the time autism is noticeable, the damage is done and chelation therapy will be of marginal benefit, if any. So perhaps what is needed is an epidemiological study of children exposed to mercury via vaccines and tooth fillings vs. children who have less exposure. Then to compare the rates of autism with presence of key genes related to metal processing in these two groups of children. This is not my professional area of expertise but I have a son with a severe genetic condition related to metal metabolism (not autism), so I have read up quite a lot. My son was not damaged by a vaccine, but I certainly feel uneasy about letting any of my other children have vaccines containing mercury or mercury amalgam fillings.
Spokespeople for the AAP are about the only people left (other than the actress Ms. Peet and vaccine patent holder Paul Offit) still willing to go out on a limb and make excuses for the practice of injecting pregnant women, infants and toddlers with high levels of mercury. That’s probably because they can see that that limb has been hanging up there, for a decade now, by a mere thin rotten thread. Mercury apologists refer to Hannah Poling, if they refer to her at all, as an isolated incidence. They’ve no reason to believe that she is an isolated incidence. They prefer to pretend that she had a pre-existing mitochondrial disorder, when there is no reason to believe that she did—she in fact had no symptoms prior to receiving nine vaccines in one doctors visit. Even Bernadine Healy, former head of the NIH, has been interviewed voicing her opinion that there is a great deal of evidence for vaccine damage, and that she believes that the government has been loath to look into the matter because they have been terrified of what they will see if they give it an honest look. Julie Gerberding, current head of the CDC, has recently confessed that the study most often cited by government officials to exonerate mercury used in vaccines, is riddled with errors and probably misleading. You speak in your article of the boy who died of chelation. Why don’t you mention that he was given the wrong drug? How many people have been harmed or died because their doctors messed up and gave them the wrong drug? It happens. If we stopped using every drug that was ever involved in a medical mistake, the pharmaceutical companies would be out of business. Which I’ve come to believe, frankly, would probably be better for the health of Americans, what with the corruption that is so deeply rooted in our medical and pharmaceutical and public health institutions. There are risks to any medical procedure. Anyone who’s looked at this issue closely has seen the degree to which the possible benefits of this procedure have been played down by the medical establishment, and the risks played up. That is because autism is, in large part, an iatrogenic disorder. The medical and government officials are deep in denial, but as this epidemic spreads, their lies are becoming apparent and unacceptable to more and more people. Yes, chelation depletes the body of other necessary metals. That is why chelation is a gradual, intermittent process, and the other metals are administered periodically and monitored. For a decade thousands of parents have been saying the same thing. For a decade those in the government health agencies that recommend the vaccine schedule, promote vaccines, and profit from their use, have been working desperately to silence those parents. The news media, in between pharmaceutical commercials, has been complicit in helping them. But you can’t silence the voices of thousands of parents who’ve watched as their children were stolen from them. They will stop at nothing to get them back. Yes, they are desperate, but this does not make them wrong. Robin Nemeth http://www.wideopenwest.com/~r_nemeth/vaccine_flyer.htm
Mercurial preservatives have been removed from most pediatric vaccines and yet (after several years of vaccines without mercury) children's autism rates are unchanged or perhaps even higher than ever. The result of the original epidemiological study that linked the two was not replicated when better studies were conducted. The link between autism and mercury in vaccines has evaporated. It is time to start looking for the real cause(s) of the disease.
Ashley - "I would have to agree, that such trace levels of Hg detected in autistic patient samples, is not nearly enough to cause toxic effects which would result in neurological damage." But you need to take into account the theory that this whole approach is based on, that these kids have impaired detox systems and autoimmune disorders. Their efflux disorder prevents them from processing out mercury (or much of any metals that they are exposed to). Injected ethylmercury crosses the blood brain barrier, bonds with oxygen to form inorganic mercury (at a much higher rate than the methylmercury found in fish)and becomes trapped in the brain for years or decades. So what goes in, stays in and continues to do damage on an ongoing basis. That ongoing injury then is addressed by cytokines, which cause neuroinflamation, which does not resolve, as the damage is on going because the mercury does not leave. (Which is why even mild anti-inflammatories like chelated fish oil improve our kids functioning and cognition.) That encephalopathy (also spurred on further by other adjuvants like the aluminum injected at the same time as the mercury) results in the symptoms of autism, according to the Vaccine Injury Compensation Programs table of covered vaccine injuries. The symptoms they list of vaccine induced encephalopathy are loss of eye contact, not responding to even familiar voices and disconnection from the world around them. Seizures are also associated, and about 30% of our kids with autism have seizure disorders. The Merck Manual says that encephalopathy is associated with unspecified GI problems, and almost ALL our kids have GI problems (According to CDC, GI problems are also a symptom of mercury toxicity). Sound like autism to you? If this theory is correct, getting the mercury out of the brain stops further neuron death as is noted, but it also allows the immune system to stand down and brain inflammation to resolve itself, and the brain can do a little healing. My 6 year old autistic son has been doing IV EDTA on and off for a year with great results. More speech, better eye contact, more affectionate, more interactive, he fights with is brother now (he never cared enough before to fight), he even potty trained (finally! Praise the Lord!) DMSA has been the standard treatment for lead poisoning since the 1950's. If your child was found to have lead poisoning today, that is exactly how he would be treated. But suddenly when it is to be used on autistic kids with metal poisoning and if found successful and would support the vaccine/autism connection, it is too dangerous to be tested? Seriously? It is already in practice! For half a century even! Can you see why parents call shenanigans on the medical authorities (and authors of biased articles like this one) for their handling of the vaccine/autism issue?
...also "there have also been several studies which indicate that a good majority of autistic patients suffer from depleted zinc levels. With this being said, giving said patients chelation therapy could have detrimental effects." When we chelate our kids, we supplement and monitor zinc levels, and many other things, taking breaks to make sure the their little bodies have a chance to build back up their minerals. We give our son regular Myers Cocktails customized for him. The only testing that has come back at all negative is that his iron was "a little low" once. There is even a product called "Chelate Mate" on the market, because mineral support during chelation is standard in our community. The current procedure for the NIH study, according to my reading, does not seem to have enough mineral support or monitoring in place. In the real world parents are doing much more than this study looks to be doing for kids. I hope that during this review of the study, that they will get better guidance from docs that are chelating autistic kids on safety measures like supplementing and monitoring.
The notion that mercury causes autism is nonsense. In the first half of the 20th century, many English speaking infants were commonly given teething powders that contained calomel, HgCl, one grain per dose. That is 65,000 micrograms HgCl per dose. That is 55,000 micrograms of mercury per dose. Many millions of doses were sold per year, with one company selling over 30 million doses in one year. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=10645305 Many children developed what is called “pink disease�, which we now know is mercury poisoning. Over 1000 children died of mercury poisoning from mercury containing medicinal agents. The 10 to 15 micrograms of mercury in vaccines due to thimerosal is negligible compared to the 55,000 micrograms of mercury infants received per dose each time they received teething powders. Thus in the first half of the 20th century many millions of children were each exposed to many thousands of times more mercury than any child has ever received from mercury containing vaccines. Why was there no epidemic of autism when many millions of infants were receiving many thousands of times more mercury than children receive today? The reason is because mercury has nothing to do with autism. People didn’t arrive at the “mercury causes autism� idea via a rational science based approach. A rational science based approach isn’t going to convince them it is wrong.
David - Actually Pinks (Acrodynia) has a great deal in common with Autism. The first paper that associated the mercury and autism, "Autism, a Novel Form of Mercury Poisoning" used autisms common symptoms to Pinks Disease as evidence of the common cause of mercury. Among the common symptoms, muscle weakness, clumsiness, rocking, unusual postures, GI dysfunction (loss of weight/appetite, vomiting and constipation), self-injurious behavior, noise sensitivity, aversion to touch and excessive pain when bumping into limbs, high incidence of asthma and other allergies, insomnia, seizures, abnormal skin sensations, baby's constant crying. As for dosage, the theory in both cases is that there is a subset of the population that is more sensitive to Hg toxicity. Which is why not all of the babies that used the teething powder got sick and died, and not all children injected with thimerosal containing vaccines develop autism. Further, ingested mercury is largely processed out of the body in someone with a healthy GI tract, and never hits the blood stream. Injecting mercury bypasses the body's natural defense against metal poisoning.
Charles - "Mercurial preservatives have been removed from most pediatric vaccines and yet (after several years of vaccines without mercury) children's autism rates are unchanged or perhaps even higher than ever." Actually, not enough time has passed to make that call yet. There was never a recall, and many parents were reporting finding full dose mercury vaccines on the shelves of their doctors offices with expiration dates as late as 2007. People ASSUMED that it was gone, but even many doctors didn't know they were still injecting it. In 2000 I asked a doctor about mercury in vaccines, and he was horribly offended and insisted that "we don't do that any more". He then had his nurse give my preemie a full dose mercury Hep B shot. I didn't find out until I pulled the lot numbers off my kids records in 2004 and saw that he was full of crap. Additionally, at the same time they started taking thimerosal out of vaccines, the CDC began recommending that pregnant women get flu shots, most flu shots are full dose thimerosal shots, and CDC refuses to even state the common sense preference that pregnant women receive thimerosal free flu shots. (BTW, No flu shots are ever safety tested on pregnant women, but CDC recommends them any way). So while babies born now get less mercury, they get it earlier. And the earlier you get it, the worse the damage. Also keep in mind that the vaccine/autism theory is that mercury is not the only problem, but the aluminum adjuvants that stimulate the immune response and the live viruses that our kids with auto immune disorders cannot handle like typical kids. But... and this is just in the early observation stage, what mom's are starting to see as we look at each other's kids, is that kids with autism born in the 90's seem to be more severely impaired than our kids now. My 6 year old son was in the first birth cohort to get only low dose mercury vaccines (called "trace" amounts, but still over EPA daily limits for their weight), and he and kids younger than him seem higher functioning than their older counterparts. We won't be able to really look at trends until beginning in 2010, and even then the flu shots during pregnancy will confound the results.
Ginger, your assertion that mercury in the gut is not absorbed is contradicted by the data. Children died of mercury poisoning from teething powders at doses thousands of times higher than the dose from vaccines. Pretty obviously enough of that mercury was absorbed to kill them. Some children with pink disease excreted more mercury in their urine in a few days than has ever been in the cumulative exposure of mercury from vaccines. No child has died of mercury poisoning from vaccines. Over a thousand died of mercury poisoning from teething powders. Presumably some of the many tens of millions of children who were exposed to mercury from teething powders and did not die would have developed autism if in fact mercury caused autism. They did not develop autism because mercury exposure does not cause autism. Only something like 1 in 500 children exposed to teething powders developed pink disease and ~1 in 10 died from it. That 1 in 500 children are sensitive to 55,000 micrograms of mercury does not suggest that 1 in 150 are sensitive to 15 micrograms. Burbacher et al showed that oral methyl mercury is absorbed better (i.e. achieves 3x higher blood levels) than the same mercury dose in injected thimerosal. Methyl mercury is the type of mercury in tuna fish. 100 grams of canned albacore tuna fish has an average of 35 micrograms of mercury.
David - I didn't say Hg was not absorbed by the gut, I said that most of it was excreted. About 90% is excreted, 10% absorbed (methylmercury). And clearly Pinks and Autism are not the exact same thing, but they have many similarities. As they do to Minamatas. As they do to the CDC's definition of mercury poisoning in children. And Burbacher proved that ingested mercury and injected mercury behaved differently once in the body. He also proved that while methyl is more readily absorbed, it does not get trapped in the brain as high a rate as ethyl, so the end product is that when you start with the same amounts of both, you end up with more ethyl mercury in the brain and it stays there indefinitely. Do we know that no children who got just enough teething powder, but didn't exhibit the rash, were not eventually diagnosed with autism? Back then autism was a psychiatric disorder caused by mom's who hated their kids and wanted them dead. They didn't take medical histories or look for mercury exposure. But babies who showed signs of Pinks in infancy and lived, has anyone gone back to see if they met DSM criteria for an ASD? I just don't know that enough data exists to measure your assertion or not. Again... they have many symptoms in common (can you acknowledge that), and the variations in exposure may account for the variations in the presentation of symptoms. But the two diagnosis were SO far apart in that time period, in two different disciplines that didn't overlap like they do now (psychiatric in the age of Freud/medical), i don't know that once a child got one diagnosis, that they would every considered for another. That is still happening now. My son was diagnosed with "Autism" and no mainstream doc every even looked for anything else. They didn't even put a hand on his forehead to see if he was warm, just looked at him not talking any more and referred him to speech therapy. Most autism cases are never medically investigated by pediatricians to see if anything else is going on their bodies. Peds are taught "no cause, no cure" and our kids medical problems are ignored. Until we go do a DAN doc who actually looks for thing like mercury and neuroinflammation and listens to stories of GI problems. So if that is the case now, why in the world would a psychiatrist making a million dollars off of mom's decades of Freudian analysis of why she secretly down deep wanted to kill her child, stop to see if the child actually had mercury poisoning? Why would it even occur to him? And once a child was diagnosed with Pinks, why would a psychiatric condition caused my evil mommies ever be considered?
In addition, thimerosal in teething powder was not being administered in the presence of aluminum. They are highly reactive with one another and each makes the other more destructive.
one more thing. CDC's description of mercury poisoning n children from their web site (don't miss the 'inability to speak' part: http://www.atsdr.cdc.gov/tfacts46.html#bookmark07 "Very young children are more sensitive to mercury than adults. Mercury in the mother's body passes to the fetus and may accumulate there. It can also can pass to a nursing infant through breast milk. However, the benefits of breast feeding may be greater than the possible adverse effects of mercury in breast milk. Mercury's harmful effects that may be passed from the mother to the fetus include brain damage, mental retardation, incoordination, blindness, seizures, and inability to speak. Children poisoned by mercury may develop problems of their nervous and digestive systems, and kidney damage." The only symptoms on that list that are not common in our children are blindness and kidney damage. But then again, I don't know how hard people have looked at their children's kidneys now that I think about it.
Ginger, what ever symptoms people with autism have in common with people with mercury poisoning, people with autism don't have the most important and diagnostic symptom of mercury poisoning. With out that symptom, they don't have mercury poisoning. That symptom is an elevated level of mercury. If someone doesn't have an elevated level of mercury, they don't have mercury poisoning. If there is no mercury present, there is no rational reason to suppose that chelation will improve anything.
DUDE! OUR KIDS HAVE MERCURY! Why do you think we are going so nuts about this issue! We test them and it is there! We have been having our kids mercury tests printed on big signs and marching them around in front of the capitol building in DC and the CDC in Atlanta for like 3 years now, and somehow people like you, who are obviously paying attention and thinking about this issue, still don't know we are finding mercury in our kids!?! Why do you think we won't let this issue go? Do you really think that there are THAT MANY "desperate parents looking for someone to blame" that would spend truck loads of cash to chelate their kids for metals that are not there and pretend that they are getting better? If that were the case, why isn't NIMH studying parents of autistic kid for delusions? 'Cause that would be one heck of a mass delusion to study! I have been doing IV EDTA chelation with my son on and off for a year. Mercury and lead keep coming out of him. No end in sight yet. And he does not have any new exposure. We can't get health authorities to do a simple study to find what percentage of autistic children, given a chelating agent, will excrete mercury in their urine! They will do studies all day long that will look at blood mercury levels, knowing full well that blood levels only show exposure in the last 30 days or so and they will do mercury excretion studies on TYPICAL kids, and say... lookie, mercury leaves the body, no problem, but CDC will not look at our autistic kids, with efflux disorders, to see if mercury is being stored in the tissue or the brain! Even THE CHELATION STUDY DISCUSSED ABOVE USES BLOOD MERCURY LEVELS! Fortunately others are actually looking in the right places and finding it: Porphyrinuria in Childhood Autistic Disorder: Implications for Environmental Toxicity, Toxicology and Applied Pharmacology, 2006. - . Blood Levels of Mercury Are Related to Diagnosis of Autism: A Reanalysis of an Important Data Set, Journal of Child Neurology, Vol. 22, No. 11, 1308-1311 (2007) - Oxidative Stress in Autism: Elevated Cerebellar 3-nitrotyrosine Levels, American Journal of Biochemistry and Biotechnology, 2008 - A Case Series of Children with Apparent Mercury Toxic Encephalopathies Manifesting with Clinical Symptoms of Regressive Autistic Disorder, Journal of Toxicology and Environmental Health, 2007 - Attention-deficit hyperactivity disorder and blood mercury level: a case-control study in chinese children, Neuropediatrics, August 2006. And wanna know something fun that sometimes happens? Parents will give their kids a challenge test for toxic metals, find no mercury , but do find lead or cadmium or arsenic or something else, start chelating to get rid of the them and after a time, kids start dumping mercury. And kids can excrete up to like 900 times what is shown on their first challenge test. Our kids have the symptoms of mercury poisoning (which are also symptoms of autism), we test them and find mercury poisoning, we chelate them for mercury poisoning and their symptoms of mercury poisoning (also symptoms of autism) improve and some even go away completely! THIS IS NOT ROCKET SCIENCE! NIH NEEDS TO RUN THE DAMN STUDIES ON THIS ALREADY! This is so absurd.
Ginger, the paper you cited "Elevated cerebral 3-nitrotyrosine Levels" actually measured mercury levels in brain specimens of people with autism postmortem. They didn't find any excess. The DeSoto paper you cite didn't find any excess either. It is well known that if mercury is present, and chelating agents are administered, that mercury will be excreted. There have been no published studies that have shown elevated and toxic levels of mercury in people with autism. People with autism are as susceptible to mercury poisoning as anyone else, but their autism is not caused by mercury. They don't have elevated mercury levels. People with elevated mercury levels don't have autism. You should look at the Faroe Islands studies by Grandjean P et al, they followed a ~1000 child consecutive birth cohort (1986-1987) with 996 cord blood mercury levels. The interquartile cord blood mercury levels were ~65 nM/L and 200 nM/L. An unrelated study by different authors looked at the incidence of autism in the Faroe Islands which included the age cohort that was tested for autism, and the 1404 children in that age group there were 5 cases of ASDs, two of autism and 3 of Asperger's. If mercury levels in the 65 nM/L level caused autism, 75% of the children in the Faroe Islands would have autism because that is what their cord blood mercury levels were. 200 nM/L is higher that what Burbacher et al found after dosing monkeys. 25% of the children in the Faroe Islands had higher mercury levels. The NIH needs to take proper ethical safeguards. Children with autism are a vulnerable population; parents of children with autism are a vulnerable population. Both need to be protected from being exploited. It is unfortunate that an industry has developed to exploit autistic children and their parents by selling them treatments they do not need and which will not help them.
Ginger, I sympathize with you but I disagree with you on many levels. This is hard thing to do, as I understand that you would do whatever it takes to help your child. As a scientist though, we are tasked with finding out what causes Autism and then determining how to treat it. The issue is what caused the Autism to begin with. As you know, this is Developmental Neurological Disorder. Several Long-Term Studies in Europe and Japan have clearly shown that after Thimerosal (the Mercury Preservative in the Vaccines) was taken out of the Vaccines that there was no drop in the incidence of Autism. If you are interested, I can get you these studies. Also, several recent studies have confirmed that Autism is related to specific genes. This does not mean that 'its all in the genes', but it does indicate that there is a genetic component. All of the evidence that most of us scientists have been able to look at does not indicate an Iatrogenic cause. If that were the case, then we should have seen a decrease in the incidence of cases in countries that have discontinued using Thimerosal in vaccines (we have not). I have been following this field for over 10 years. I was on the Thimerosal Bandwagon when I first heard about the Mercury preservative in the vaccines. As the years have progressed, I am not convinced and I used to study Developmental Neuroscience in my lab. I so wanted this to be the answer. It seems so plausible. But as is often the case in science, things are always more complicated than we would like them to be. The scientific community needs to take a leading role in educating the public and building up trust. I personally feel, that if parents with Autistic Children want to test this hypothesis, then we should do it and put the issue to rest. This whole debate says more about the poor state of scientific credibility with the general public than it does about the state of autism research.
Some quick comments on this argument - Blood-mercury levels are pretty much meaningless in people with organomercury poisoning because the mercury has already passed through into storage in the brain by the time they express symtoms. Measuring fat levels, hair levels or urine levels following cleation would make more sense. We evolved to handle heavy metals entering our bodies through ingestion or skin-exposure by excreting what we could and sequestering the blood-borne metal ions we couldn't in fat stores. To expect the body to excrete injected mercury as it would surface or GI-exposed mercury is irrational. We shouldn't be injecting infants with developing brains with mercury. Period. We also shouldn't be surprised that said injections, at whatever level, produce ill affects on that developing brain and other organs when that infant enters a growth-spurt which consumes some of the mercury-storing fat, or recieves their last set of innoculations. It's also unimportant to bring into this conversation levels of mercury consistent with causing death in either infants or children, much less adults. The important dosage to examine is that between none and the level which causes undeniable symptoms of mercury poisoning... those subtle levels which may still have an effect on developing brains cells without being obviously heavy metal-caused. Additionally to have Autism you need to have a physician looking for Autism. Often they do this at the cost of looking for mercury-toxicity because there was no identifyable point-exposure to explain the poisoning. I'm still on the fence on this whole issue. I'm a geneticist by training, so I'd be looking mostly at gene-environment interactions to predispose certain individuals to express their disorders. And just as it's not correct to rule out a gene for not explaining 100% of disease incidence, it's uninformed to dismiss organomercury exposure as a potential cause of an Autism-like syndrome because it fails to cause autism in every child supposedly exposed at the same levels.
Oh, and with maternal mercury contamination levels, the increase in breastfeeding (which for most things is good), fat-loss IN mothers while breastfeeding and biological food-chain amplification... saying that we (supposedly) cut out thimerosol usage in US and European vaccines given to children and infants a decade ago does not actually dismiss the entire argument as to why Autism levels aren't dropping. After all, most adult vaccinations are still preserved with Thimerosol. If some cases of Autism are mercury-related we may see a subtle fall over the next 5 generations or so, but that may be the length of time it takes to get a widespread mercury contamination out of our species. Just a thought. Also, why do rises in diagnoses of Autism follow distributions of Thimerosol-containing vaccines to third-world nations... nations whose level of autistic children has exploded since the introduction of childhood innoculations, even though the background genetic variation has not changed? That suggests environmental issues. Or more access a broader range of US-diagnostic criteria for pre-existing diseases *grins*. As I said, I'm still on the fence on this one.
Lacey, canned albacore tuna fish has an average of ~0.35 ppm mercury in it. One ounce of tuna fish has almost as much mercury as a thimerosal containing vaccination. Burbacher et al showed that oral methyl mercury (the kind in tuna fish) is better absorbed than injected thimerosal. That is it produces higher blood mercury levels by direct measurement in monkeys. The quantity of mercury in virtually everyone's diet is higher than that in vaccines. Mercury declines over time if exposure is eliminated. The half life is measured in weeks. Five generations? There is absolutely no basis for suggesting a half life of even one year, let alone one generation. The most likely explanation for the observation that there is no decline in autism rates after thimerosal has been removed is because thimerosal had nothing to do with autism in the first place. How come the mercury from teething powders didn't take 5 generations to be purged?
David - thank you so much for your very informative and perspicuous comments. Indeed, at one point I was going to advise you to simply 'throw in the towel' - there's no way to win an argument with an ignorant person. Then I realized just how much I was learning from your posts and how you were helping me notwithstanding the futility of your 'argument' with Ginger et al. So please don't despair. Your words ARE being heard. Just not by those to whom you've directed them explicitly. Please keep 'm coming. Thanks!
Karl, thanks. I appreciate that fighting against the irrationality of the anti-vaccine groups is something that far too many are inhibited from doing because of their bullying. We have seen people die from measles because of the hysteria that Wakefield’s fraud produced. Brian Deer is to be greatly commended because he exposed Wakefield’s fraud and stood up to Wakefield’s bullying (at great personal risk) and was completely vindicated. I am reminded of one of the letters of thanks that a senior physician sent to Brian Deer saying (I paraphrase), "you have saved more lives than I will in my entire career". I am reminded of the saying by Edmund Burke, “All that is necessary for the triumph of evil is for good men to do nothing.� Scientists not speaking out against irrationality is to let irrationality and the evil persons who foster and exploit that irrationality triumph.
I must confess I'm still slightly confused by your argument. If mercury levels are high in everyone's diet, couldn't that help explain the continuing increase in autism rates, even after thimerosal use is discontinued? Also, was the half-life you mentioned for blood levels of mercury, or adipose levels? If it's only been measured in the blood, then the adipose sequestration line of reasoning still makes sense. This is especially true if autism turns out to be related to the inability of the body to purge mercury, making some individuals more sensitive to the low dietary levels that everyone is experiencing. A possible confounding effect could be that childhood vaccinations provoke a poorly timed immune response during development, unrelated to any mercury in the vaccines themselves, but devastating to individuals with accumulated mercury from dietary/prenatal sources. Or maybe it's not mercury alone but some combination of metals, perhaps exacerbated by the vaccine-immune response, which chelating could still help? This isn't my area of expertise, but I still haven't seen an airtight rebuttal of the mercury poisoning hypothesis (though I think you have mostly discredited the thimerosal connection and vaccines may be entirely coincidental).