Reviewing the theory of a thimerosal based etiology for the autism spectrum: A partial review of Generation Rescue's 25 myths
I thought the best way to focus on this will be to look at certain myths in Generation Rescue’s “25 Mercury Myths” (Generation Rescue, 2005).
“There is no evidence to suggest that autism is genetic. No autism gene has ever been found and the search will be endless - how can you have a gene for a mythical condition? Autism is mercury poisoning. What is true is that certain children may have an impaired ability genetically to detoxify heavy metals from their systems. These children are more likely to be affected by mercury exposure. However, all children, and adults, if given too much mercury will manifest symptoms of mercury toxicity, which we call "autistic" symptoms. All children born from 1991 forward who received all recommended vaccines were injected with levels of mercury that dramatically exceeded safety levels set by the Environmental Protection Agency for adults. Mercury has become ubiquitous in our environment: in fish and other foods, water, and air. Exceedingly high doses of mercury exposure can result in death - it is that neuro-toxic and damaging to the human body. Two drops of dimethylmercury spilled onto the gloved hand of a Dartmouth chemistry professor, a leader in a study investigating mercury's causal role in cancer, resulting in the progressive loss of her balance, speech, vision, and hearing, and ultimately lead to her coma and death within a year of the exposure.”
No gene has been found which causes autism, that is correct. If autism is mythical why does there seem to be certain cognitive traits (strengths and weaknesses) that have been identified in the research. Is this a departure from what is known about other heavy metal toxicity? Why do older persons who have been exposed to mercury not receive the diagnostic of autism then, it seems there are important dissimilarities.
“It is impossible to have a "genetic epidemic." Since 1991, there is a very real and dramatic rise in the incidence of autism and other neurodevelopmental disorders. In the 1970s, the incidence of autism was 1 in 10,000 children. In 1986, the rate was 1 in 2,500. Today the rate is 1 in 150. It has been estimated that one in six children have some type of learning disability. Epidemics can happen in 10 years, genetic changes to populations require many generations.”
Where is the increase evidenced? Depending on the data, this may or may not be valid, the definition does not attempt to answer for other factors such as change in criteria, increased knowledge, and more precise diagnostic tools. In the 1970s the mean prevalence for autism was (3.27) per 10,000 by the way; if we include the whole autism spectrum then we have 13.7 per 10,000. Also, the present prevalence is probably best described as 1 in 166. While genetic changes take many generations, perhaps knowledge of the various ways of being human take even longer.
“There is a growing body of evidence that children properly treated for mercury poisoning fully recover normal functioning and are indiscernible from their neurotypical peers. Any toxicologist will tell you that mercury poisoning represents a temporary, treatable state. Thorough removal of mercury will resolve most or all of the symptoms. Autism is only life long if mercury poisoning is never treated”
This would be the appropriate time to cite peer reviewed research clearly demonstrating this, this is absent.
“This myth persists despite being refuted by a wide range of scientists, policy makers, and health care organizations. All the available data points to an epidemic. Between 1992-2002, the Department of Education estimates that there has been a 714% increase in the number of autistic children. In the 1970s, autism was estimated to occur in 1 in 25,000 children. Between 1970 and 1990, that number increased to about 1 in 2,500. Today, the CDC acknowledges the number is about 1 in 166, even Eli Lilly, the maker of Thimerosal, says it's 1 in 150. Many believe it is closer to 1 in 125. The anecdotal evidence that we are experiencing an epidemic is overwhelming. If there is no epidemic, then where are all the autistic adults? Ask any doctor, teacher, or day care worker who has been around children for 20 or more years, and they will tell you that the epidemic is unprecedented. What parent, either now or 20 years ago, does not notice that their child who spoke at one year is no longer speaking, or that their child does not respond to their name or look them in the eyes, or is displaying odd, repetitive behaviors like hand-flapping, spinning, and rocking that no other child is doing? Did those parents 20 years ago not notice these things?”
Where is this refuted via research? I have dedicated other posts to why the education data should never have been used to track prevalence or incidence. A Photon In the Darkness (2005) points out that the plural of anecdote is not data. By the way what was the average age of diagnosis twenty years ago; maybe we are not always as good of observers as we think. Also, twenty years ago Autism was a new diagnosis (placed in DSM-III, 1980).
“The symptoms of autism and other neurodevelopmental disorders are identical to the symptoms of mercury poisoning. The rapid rise in the number of these disorders corresponds to the dramatic increase in the amount of Thimerosal (49.6% ethylmercury by weight) given in recommended vaccines to children under two years of age. With the addition of two new vaccines in the early 1990s, the amount of ethylmercury increased 246% with most of this increase being given within the first six months of life when an infant's neural, detoxification, and immune systems are all undergoing rapid development. Equally damaging, the vaccines were given much earlier in a child's life, when the capacity to detoxify is still developing. Numerous studies demonstrate again and again the causal link between neurodevelopmental disorders and mercury, regardless of the source of exposure. Finally and most definitively of all is that when mercury is removed from these children via chelation or other means of detoxification, their symptoms resolve.”
There seems to be important differences, such as the shaking that is seen in mercury poisoning. Again correlation is not causation, there are other correlates as well. No study demonstrates the causal link between autism and mercury, this is in part because, such would never get past an ethics review board. Where is the research?
“You could analyze the data the government maintains through its "Vaccine Adverse Events Reporting System" and compare the data they already have on children who received Thimerosal-containing vaccines against children who did not receive Thimerosal in their vaccines. This study has already been done by Mark & David Geier and showed a high correlation between Thimerosal dosing and neurological disorders:”
Correlation is not causation.
“You could compare the symptoms of mercury poisoning and the symptoms of autism and see how similar they are. This study has already been done and demonstrated that the symptoms of autism and the symptoms of mercury poisoning are exactly the same:”
Except for the instances where they are not similar.
“You could administer a chelating agent to remove heavy metals, including mercury, to a group of autistic children and to a group of neurotypical children and measure the amount of mercury coming out of the children to see if there are any differences. This study has already been done by Jeff Bradstreet et.al. and showed that autistic children excrete significantly more mercury than neurotypical children:”
Yes, but that does not mean mercury caused the autism. Also, a more equivalent control sample would have been desirable.
“You could inject a group of mice with Thimerosal in doses that proportionally mimic the timing and amount received according to the recommended vaccination schedule and compare these mice to a control group for neurological development. This study has already been done by Mady Hornig et al. and showed that a subset of mice with genetic detoxification impairments who received Thimerosal injections developed "autistic symptoms":”
To my knowledge we have no protocol for identifying autistic mice.
“You could run a trial of 31 autistic children where you chelated patients over the course of twelve months and had parents videotape their children and test urine and fecal samples for toxic metals every other month. You could then compare the children's progress and symptoms from the beginning to the end of treatment. This study was done by Dr. Rashid Buttar and he made the following statement before Congress.”
The videotape is not sufficient to show causation, this is due to observer drift. This also never made it to a peer reviewed journal.
“Generation Rescue believes autism is an issue of toxicology. Yet, you never hear from a toxicologist saying there is no correlation between autism and mercury. This is because toxicologists know that the link is likely. Hearing a psychiatrist comment on mercury toxicity is like seeking the opinion of a urologist for a new heart procedure. It doesn't make sense to accept the expertise of people who have no experience in the field of heavy metal to.”
Anyone can make a criticism, the criticism has to stand on its own merit. Same goes
for the validity of an experts opinion, it has to stand on its own merit.
“In May 2004, the Institute of Medicine released a 216-page report titled Immunization Safety Review: Vaccines and Autism and concluded that there did not appear to be a causal link between Thimerosal and the autism epidemic. This study was paid for by the CDC, a conflict in of itself, and there is growing evidence that the conclusion was pre-ordained before any research was done. Regarding the potential link between mercury and autism, Dr. Marie McCormick, Committee Chair of the IOM study, in a recently released transcript, stated (before any research had been done), "We are not ever going to come down that it is a true side effect." Much of the IOM's conclusion was based on the aforementioned CDC and Danish studies - there was no primary research done. This lack of new, primary research is a critical point: the IOM's conclusion was largely based on the studies discussed in Myths 17 & 18 above that are controversial flawed.”
Its seems both sets are flawed. The Danish studies are mire by conflicts of interest and the others by lack of scientific rigor. This is inconclusive.
I think covering the other myths would involve me repeating earlier points.
The data so far seem inconclusive either way. For my part I don’t think the thimerosal theory can hold up in the absence of the proposed epidemic; I take the position that there is no epidemic. Maybe, ultimately the ball is back in the court of the advocates of this theory. They will have to conclusively and repeatedly show the effectiveness and safety of chelation using research that demonstrates causation, and publish in peer reviewed journals. They will also have to effectively demonstrate an increase in autism exists, and they will have to deal with the ethical questions that arise from attempting to remove autism from children. Until this is done chelation will remain pseudo-scientific.
A Photon in the darkness. 2005. http://photoninthedarkness.blogspot.com/2005/09/locked-in-and-threw-away-key.html
Accessed September 6, 2005
Chakrabarti, S., & Fombonne, E. (2001). Pervasive developmental disorders in preschool children. Journal of the American Medical Association, 285, 3093-3099.
Generation Rescue. 2005. http://www.generationrescue.org/index2.html
Accessed October 7, 2005.