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Thimerosal Containing Vaccines, Part III

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The Convincing Evidence

by F. Edward Yazbak MD, FAAP

PubMed is a service of the US National Library of Medicine (NLM) of the US National Institutes of Health. According to its main page, “PubMed comprises more than 20 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.”

On March 25, 2011, I accessed PubMed and searched for “thimerosal, vaccine”.

I found 396 citations, the most recent of which (listed as # 1- PMID: 21350943) published on-line February 25, 2011. It was titled “Integrating Experimental (In Vitro and In Vivo) Neurotoxicity Studies of Low-dose Thimerosal Relevant to Vaccines” and authored by Dr. J G Dórea of the Faculty of Health Sciences, Universidade de Brasília, Brazil. This article will be discussed in some detail later.

Readers interested in following this discussion may want to access PubMed at Alternative searches for “thimerosal vaccine”, “vaccine, thimerosal” or “vaccine thimerosal” will also lead to the same listing.

The 396 titles with authorship and publication details are listed 20 per page on 20 pages. []

As of March 25, 2011, there were only three listings for the year: #3 (PMID: 21252391), #6 (PMID: 21185424) and the Dórea paper.

Not all 396 listings deal with the safety vs. neurotoxicity of Thimerosal or of Thimerosal-containing vaccines (TCV), the subject of this three-part series. For example the article listed as # 2 is a report from France of a “case of allergic contact dermatitis three weeks after the H1N1 vaccine, probably involving thimerosal additive.”


The reason for this tedious exercise, probably the first of its kind, is simply to try to determine when peer-reviewed articles related to toxicity /neurotoxicity of Thimerosal-containing- vaccines (TCV) - both pro and con – were first published. The fact that Thimerosal causes allergic reactions such as reported in the publication listed as #2 has been known and reported for decades and is not relevant to this review.

As mentioned in Part 1 and II, the CDC, the FDA and WHO usually start a discussion of the issue of Thimerosal in vaccines by mentioning that the mercury preservative has been used since the 1930s, thus suggesting that it must have been safe and effective.

What those agencies are careful not to ever mention is that the very first article related to Thimerosal in vaccines on PubMed (presently listed as # 396 (PMID: 14249458) was published in October 1964, thirty four years after the 1930s.

[I started practicing pediatrics in 1964 and was just as interested in vaccines then as I am now. I can safely say that I had never heard of the Journal of Pharmaceutical Sciences (Elsevier) where that article was published and that it certainly was not readily available to most practicing US pediatricians at the time.]

The next listed article (presently listed as # 395 (PMID: 14253616) was by the same authors and was published in the following issue of the same journal in November 1964: “Thimerosal as a preservative in biological preparations. 3. Factors affecting the concentration of thimerosal in aqueous solutions and in vaccines stored in rubber-capped bottles.

For some reason, the second part of that apparent 3-part series was not listed.

Those two Birner & Garnet articles were followed by a very long silence probably because no US pediatrician in his right mind, including this writer, could have ever dreamed that FDA-licensed pediatric vaccines on the market contained any more than an infinitesimally small and innocuous amount of the mercury preservative.

Listing # 394 (PMID: 4283530) was a German article published in 1974-1975, ten years after the Birner & Garnet articles that reported allergic reactions to injected gamma globulin.

There were four articles published in 1975, presently listed as # 393 (PMID: 1053237), 392, 391 and 390. The latter published in the Journal of Clinical Microbiology in December 1975 was by John R. Pemberton, of the Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, Iowa. []

It is titled “Retention of mercurial preservatives in dessicated biological products” and is the very first full length article on the subject available for downloading.

The last paragraph of the article should make anyone shiver thirty six years later.

“The data reported here and in previous reports (2, 3) indicate that a large percentage of formaldehyde, phenol and mercurial preservative is retained by biological products during the usual lyophylization process. These preservatives are not proportionately removed with the liquid portion of the product as might be expected. Investigators should be cautious when using preserved and lyophilized biological products in preservative-sensitive systems. Caution should also be exercised with products intended for certain immunological uses, as these preservatives evidently concentrate in the micro-environment of lyophilized antigenic material, which could denature the antigen.”

Obviously most of us caring for babies never particularly followed veterinary research at the time and the Journal of Clinical Microbiology was not exactly a journal pediatricians often picked up on a lazy Sunday afternoon in the seventies.

Only seven more articles were published during the 70’s, # 389 (PMID: 799865) to # 383 (PMID: 118635)

There were 26 PubMed-listed publications on the subject during the 1980’s, starting with PMID: 6447032 and 25 publications from 1990 to 1999 (PMID: 2137393-9447766)

In all, there were 64 PubMed listings related in some way to Thimerosal from the 1930s to 1999, an average of 1 publication a year. The first two articles listed in 1999 were reports of allergic reactions to Thimerosal and not relevant to this discussion.

The very first publication about the present Thimerosal in vaccines controversy was “Notice to Readers: Thimerosal in Vaccines: A Joint Statement of the American Academy of Pediatrics and the Public Health Service”, published on July 9, 1999 and presently listed as # 329 (PMID: 10418806)

Over 300 articles on issues related to Thimerosal in vaccines were written, peer-reviewed and published in the last 12 years. On average, there was 1 publication per year from the late 1930’s to 1999 vs. more than 25 publications per year from 1999 to April 2011.


Just to compare publication dates and listings, I searched PubMed for “Vaccine” and found 163,872 listings, the first about an article in the BMJ published on May 9, 1903. For those readers interested, that complete article, “A lecture on therapeutic inoculations of bacterial vaccines and their exploitation in the treatment of disease” by A E Wright is available at []

A similar search for “Disease” yielded 2,572,961 listings, starting with “On a diminution, in consequence of Disease, of the Area of the Aperture, by which the left Auricle of the Heart communicates with the Ventricle of the same side” by John Abernethy. This article published in 1809 in Medico-Chirurgical Transactions is available at []

Lastly a PubMed search for “Thimerosal” yielded 1405 listings, the first of which “Infrared method for the determination of ethanol and acetone in thimerosal tincture N.F.” by Gronau et al. published in 1962, also in the Journal of Pharmaceutical Sciences.

Listing # 1404, “Studies on immunity in anthrax. X. Gel-adsorbed protective antigen for immunization of man” by Puziss & Wright was published in January 1963.

For those interested in the Anthrax vaccine saga, the full article is available at []

That very first publication reporting on the use of the mercury preservative in a vaccine was not exactly a vote of confidence. According to the authors:

“Gel-adsorbed anaerobic antigens preserved with 1:10,000 thimerosal were unstable on storage at 4 C; replacement of this preservative with 1:40,000 benzethonium chloride produced a more stable product. Addition of 0.0009% formalin further increased the stability during accelerated aging at 37 C.”

Listing # 1403 was the above-discussed October 1964 study by Birner & Garnet.

Given the fact that pediatric vaccines have been recommended and used “since the 1930’s”, the paucity of research for decades into a key vaccine ingredient is at best shocking and at worst damning.


Dr. Jose Dórea who wrote the most recent PubMed thimerosal in vaccines paper (listed as #1 as of March 25, 2011) authored and/or co-authored 9 other peer-reviewed PubMed-listed publications.

Most relevant to this presentation were the following two older publications reporting some very carefully conducted research:

Hair mercury in breast-fed infants exposed to thimerosal-preserved vaccines. Marques RC, Dórea JG, Fonseca MF, Bastos WR, Malm O. Eur J Pediatr. 2007 Sep;166(9):935-41. Epub 2007 Jan 20. PMID: 17237965
“…the Hg exposure corrected for body weight at the day of immunization was much higher from thimerosal- EtHg (5.7 to 11.3 microgHg/kg b.w.) than from breastfeeding (0.266 microgHg/kg b.w.). While mothers showed a relative decrease (-57%) in total hair-Hg during the 6 months lactation there was substantial increase in the infant's hair-Hg (446%). We speculate that dose and parenteral mode of thimerosal-EtHg exposure modulated the relative increase in hair-Hg of breast-fed infants at 6 months of age.”

Neonate exposure to thimerosal mercury from hepatitis B vaccines. Dórea JG, Marques RC, Brandão KG. Am J Perinatol. 2009 Aug;26(7):523-7. Epub 2009 Mar 12. PMID:19283656
“Infant exposure to ethylmercury (EtHg) has not only increased but is starting earlier as a result of the current immunization schedule that uses thimerosal-containing vaccines (TCVs). Although vaccination schedule varies considerably between countries, infants in less-developed countries continue to be exposed to EtHg derived from more affordable TCVs. We studied the exposure of newborns to EtHg from hepatitis B vaccines; hospital records (21,685) were summarized for the years 2001 to 2005 regarding date of birth, vaccination date, and birth weight. Most of the vaccinations occurred in the first 24 hours postdelivery; over the 5 years, there was an increase in vaccinations within hours of birth (same day), from 7.4% (2001) to 87.8% (2005). Nearly 94.6% of infants are now being vaccinated within the first 24 hours. Range of mercury exposure spread from 4.2 to 21.1 microg mercury/kg body weight for those receiving TCVs with the highest thimerosal concentration; these exposure levels are conservative for 2% of children receiving vaccines within 2 to 3 postnatal days, when they are still going through physiological postnatal weight loss. Because of the particular timing (transitioning from in utero to ex utero metabolism) and specific aspects of exposure (i.e., parenteral mode, bypassing gastroenteric barriers) and dose (related to vaccine manufacturer and with variation in birth weight), this study reveals critical issues that can modulate toxicokinetics and toxicodynamics of organomercurials in neonates.


Integrating Experimental (In Vitro and In Vivo) Neurotoxicity Studies of Low-dose Thimerosal Relevant to Vaccines
[The recent Dórea review dealing with the Thimerosal / vaccine issue]

This latest Dórea publication is impressive and the culmination of years of research.

Dr. Jose Dórea serves on the Faculty of Health Sciences at the Universidade de Brasilia (UnB), one of Brazil’s largest and most prestigious universities.
UnB’s motto, “A universidade que inspira”, is itself inspiring, as is evidently the research going on within its walls with more than 250 research-groups investigating close to 890 different areas in 400 laboratories. The university offers 61 undergraduate, 49 Master’s and 27 Doctoral programs.

Dr. Dórea’s pro-vaccine stance is evident in the first sentence of his concluding remarks “Without vaccination it would be impossible to eradicate or control infectious diseases that otherwise would be devastating to children…” and his research was supported by a grant by The National Research Council of Brazil.

Because of its conclusions, the publication must have been peer-reviewed up and down and sideways several times.

The author selected and attached 81 references some of which I had not previously seen. Twenty eight of those references were published in 2009-2010.

Because of copyright issues, I am unable to feature the full publication on Vaccination News but I certainly encourage everyone to get it, read it and keep it for future reference.

I will attempt to do this great review justice.


Dr. Dórea started his abstract by stating:

“There is a need to interpret neurotoxic studies to help deal with uncertainties surrounding pregnant mothers, newborns and young children who must receive repeated doses of Thimerosal-containing vaccines (TCVs). This review integrates information derived from emerging experimental studies (in vitro and in vivo) of low-dose Thimerosal (sodium ethyl mercury thiosalycilate.)”

After carefully reviewing the literature and selecting the most appropriate and convincing articles, the author concluded that:
  • The selected studies revealed activity of low doses of Thimerosal against isolated human and animal brain cells consistent with mercury neurotoxicity
  • Doses “relevant to TCV exposure possess the potential to affect human neurodevelopment”
  • Animal studies reveal that exposure to the mercury in Thimerosal can lead to accumulation of inorganic mercury in the brain
  • There were no studies on the neurotoxicity of ethyl mercury in the presence of Aluminum, an adjuvant added to some TCVs now in use
This careful literature review also indicated that:
  • Thimerosal in concentrations such as those presently in pediatric vaccines still used in many countries “is toxic to cultured human brain cells and to laboratory animals”
  • The present use of TCVs in developing countries “is counterintuitive to global efforts to lower Hg exposure and to ban Hg in medical products”
  • The continued use of TCVs requires evaluation of “a sufficiently nontoxic level of ethylmercury compatible with repeated exposure (co-occuring with adjuvant –Al) during early life.”
The author ended by appropriately pointing out that more studies were urgently needed because “despite demonstrable toxicity of Ethyl Mercury”, Thimerosal-containing vaccines were still being used in increasing quantities in developing countries even though real concerns about pregnant women and newborns receiving such vaccines existed.


The studies that Dr. Dórea carefully selected and on which he based his conclusions and recommendations were listed in two tables:

Table 1: “Summary of toxicity studies of low-dose Thimerosal (or ethyl mercury) and aluminum in human and animal cultured-neural-cells.”
Studies by: Geier et al. (2009), Geier et al. (2010), James et al. (2009), Herdman et al. (2006), Parran et al. ( 2005), Yel et al. (2005), James et al. (2005), Humphrey et al. (2005), Waly et al. (2004), Toimela and Tahti (2004), Baskin et al. (2003), Lawson et al.(2007), Ueha-Ishibashi et al. (2004), Jin et al. (2004), Song et al. (2000), Chanez et al. (1989), Wyrembek et al, (2010), Minami et al. (2009, and Rush et al. (2009).

Table 2: “Animal studies of neurotoxic preservative-thimerosal and adjuvant-Al at doses relevant to vaccines.”
Studies by: Blair et al. (1975), Burbacher et al. (2005), Hewitson et al. (2010), Hewitson et al. (2010), Gassett et al. (1975), Olczak et al. (2009), Olczak et al. (2010), Olczak et al. (2010), Orct et al. (2006), Minami et al. (2010), Minami et al. (2007), Hornig et al. (2004), Berman et al. (2008), Petrik et al. (2007), Shaw and Petrick (2009), Hunter et al. (2010).

The following are quotes from some of the above-listed publications:

[2004] Hornig et al.: “We hypothesized that autoimmune propensity influences outcomes in mice following thimerosal challenges that mimic routine childhood immunizations. Autoimmune disease-sensitive SJL/J mice showed growth delay; reduced locomotion; exaggerated response to novelty; and densely packed, hyperchromic hippocampal neurons with altered glutamate receptors and transporters. Strains resistant to autoimmunity, C57BL/6J and BALB/cJ, were not susceptible. These findings implicate genetic influences and provide a model for investigating thimerosal-related neurotoxicity.” [PMID: 15184908]

[2009] James et al.: Lymphoblastoid cells (LCLs) derived from autistic children and unaffected controls were used to assess relative concentrations of reduced glutathione (GSH) and oxidized disulfide glutathione (GSSG) in cell extracts and isolated mitochondria as a measure of intracellular redox capacity. The results indicated that the GSH/GSSG redox ratio was decreased and percentage oxidized glutathione increased in both cytosol and mitochondria in the autism LCLs. Exposure to oxidative stress via the sulfhydryl reagent thimerosal resulted in a greater decrease in the GSH/GSSG ratio and increase in free radical generation in autism compared to control cells. Acute exposure to physiological levels of nitric oxide decreased mitochondrial membrane potential to a greater extent in the autism LCLs, although GSH/GSSG and ATP concentrations were similarly decreased in both cell lines. These results suggest that the autism LCLs exhibit a reduced glutathione reserve capacity in both cytosol and mitochondria that may compromise antioxidant defense and detoxification capacity under prooxidant conditions. [PMID: 19307255]

[2010] Hewitson et al.: “This longitudinal, case-control pilot study examined amygdala growth in rhesus macaque infants receiving the complete US childhood vaccine schedule (1994-1999)…Vaccine-exposed and saline-injected control infants underwent MRI and PET imaging at approximately 4 and 6 months of age, representing two specific timeframes within the vaccination schedule. Volumetric analyses showed that exposed animals did not undergo the maturational changes over time in amygdala volume that was observed in unexposed animals… results suggest that maturational changes in amygdala volume and the binding capacity of [(11)C]DPN in the amygdala was significantly altered in infant macaques receiving the vaccine schedule.”[PMID: 20628439]

[2010] Olczak et al.: “Numerous neuropathological changes were observed in young adult rats which were treated postnatally with thimerosal. They included: ischaemic degeneration of neurons and "dark" neurons in the prefrontal and temporal cortex, the hippocampus and the cerebellum, pathological changes of the blood vessels in the temporal cortex, diminished synaptophysin reaction in the hippocampus, atrophy of astroglia in the hippocampus and cerebellum, and positive caspase-3 reaction in Bergmann astroglia. These findings document neurotoxic effects of thimerosal, at doses equivalent to those used in infant vaccines or higher, in developing rat brain, suggesting likely involvement of this mercurial in neurodevelopmental disorders.” [PMID 21225508]

[2010] Wyrembek et al.: Many neurotoxic effects of thimerosal have been described… We examined, using electrophysiological recordings, thimerosal effects on GABA and NMDA-evoked currents in cultured hippocampal neurons... following exposure for 60-90 min to 1 or 10 μM thimerosal, there was a significant decrease in NMDA-induced currents (p<0.05) and GABAergic currents (p<0.05). Thimerosal was also neurotoxic, damaging a significant proportion of neurons after 60-90 min exposure; recordings were always conducted in the healthiest looking neurons…The results reveal complex interactions of thimerosal and mercuric ions with the GABA(A) and NMDA receptors... The neurotoxic effects of both mercurials are interwoven with their modulatory actions on GABA(A) and NMDA receptors, which most likely involve binding to these macromolecules. [PMID: 21224507]


Two other publications not listed in the Dorea paper deserve mentioning:

Young et al. [2008 - GWU – PMID: 18482737]:
“The study evaluated possible associations between neurodevelopmental disorders (NDs) and exposure to mercury (Hg) from Thimerosal-containing vaccines (TCVs) by examining the automated Vaccine Safety Datalink (VSD). A total of 278,624 subjects were identified in birth cohorts from 1990-1996 … Consistent significantly increased rate ratios were observed for autism, autism spectrum disorders, tics, attention deficit disorder, and emotional disturbances with Hg exposure from TCVs. By contrast, none of the control outcomes had significantly increased rate ratios with Hg exposure from TCVs…

Kempuraj et al. [2010 -Tufts U - PMID: 20222982]:
“Mercury is known to be neurotoxic, but its effects on the immune system are less well known. Mast cells are involved in allergic reactions, but also in innate and acquired immunity, as well as in inflammation. Many patients with Autism Spectrum Disorders (ASD) have “allergic” symptoms; moreover, the prevalence of ASD in patients with mastocytosis, characterized by numerous hyperactive mast cells in most tissues, is 10-fold higher than the general population suggesting mast cell involvement.
Human leukemic cultured LAD2 mast cells and normal human umbilical cord blood-derived cultured mast cells (hCBMCs) were stimulated by HgCl2 (0.1-10 μM) for either 10 min for beta-hexosaminidase release or 24 hr for measuring vascular endothelial growth factor (VEGF) and IL-6 release by ELISA... HgCl2 induced a 2-fold increase in b-hexosaminidase release, and also significant VEGF release at 0.1 and 1 μM (311 ± 32 pg/106 cells and 443 ± 143 pg/106 cells, respectively) from LAD2 mast cells compared to control cells (227 ± 17 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to the proinflammatory neuropeptide substance P (SP, 0.1 μM) had synergestic action in inducing VEGF from LAD2 mast cells. HgCl2 also stimulated significant VEGF release (360 ± 100 pg/106 cells at 1 μM, n = 5, p < 0.05) from hCBMCs compared to control cells (182 ± 57 pg/106 cells), and IL-6 release (466 ± 57 pg/106 cells at 0.1 μM) compared to untreated cells (13 ± 25 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to SP (5 μM) further increased IL-6 release...
The results of the present study support the biological plausibility of how mercury could contribute to ASD pathogenesis by inducing VEGF and IL-6 release from mast cells, and as a result disrupt the BBB and thus permit brain inflammation.”


On February 9, 2004 the Institute of Medicine (IOM) Immunization Safety Review Committee met to dispose once and for all, of the wild notion that autism was somehow related to MMR vaccination and or Thimerosal-containing vaccines.

On Wednesday March 30, 2011, I accessed the information still available on the IOM web site and found the following:

Immunization Safety Review: Vaccines and Autism
Released: May 14, 2004
Type: Consensus Report
Topics: Children, Youth and Families, Public Health
Activity: Immunization Safety Review
Board: Board on Population Health and Public Health Practice
This eighth and final report of the Immunization Safety Review Committee examines the hypothesis that vaccines, specifically the measles-mumps-rubella (MMR) vaccine and thimerosal-containing vaccines, are causally associated with autism. The committee reviewed the extant published and unpublished epidemiological studies regarding causality and studies of potential biologic mechanisms by which these immunizations might cause autism.
The committee concludes that the body of epidemiological evidence favors rejection of a causal relationship between the MMR vaccine and autism. The committee also concludes that the body of epidemiological evidence favors rejection of a causal relationship between thimerosal-containing vaccines and autism. The committee further finds that potential biological mechanisms for vaccine-induced autism that have been generated to date are theoretical only.
The committee does not recommend a policy review of the current schedule and recommendations for the administration of either the MMR vaccine or thimerosal-containing vaccines. The committee recommends a public health response that fully supports an array of vaccine safety activities.
In addition, the committee recommends that available funding for autism research be channeled to the most promising areas. The committee makes additional recommendations regarding surveillance and epidemiological research, clinical studies, and communication related to these vaccine safety concerns.

Three questions need to be asked:
  1. If the IOM committee was not impressed with the biomedical studies presented, then why not invite or order researchers in the US and elsewhere to further investigate the issues? Why close the door and say “No more research should be done”?
  2. Since when is theoretical evidence dismissed simply because it is theoretical?
  3. What scientific argument supports the committee’s assertion that epidemiological evidence in questionably funded studies is more compelling than evidence presented by independent researchers performing biomedical evaluations and reviews?

On May 11, 2005, I wrote a personal letter to IOM President Harvey V. Fineberg, MD, PhD questioning the committee’s findings and requesting a review of the matter. [/node/19921]

I also submitted to the IOM President a list of impressive research on Thimerosal that had been peer-reviewed and published since the 2004 meeting. [References 1-12 attached]

Fineberg never offered me the courtesy of a response!


As exposed in Part II of this series, WHO accepted the IOM Immunization Safety Review Committee’s 2004 verdict as Gospel truth and has used it successfully since then to close the door to new research and to justify the continued use of Thimerosal in vaccines.

Thankfully, independent investigators did not listen to the committee and persisted in designing and carrying out excellent research since then.

Without their efforts and Dr. Dórea’s careful review of their results to date, no one would have known how much more we have learned on the subject of Thimerosal (and Al) since that supposedly “final” 2004 IOM Immunization Safety Review Committee meeting and its contrived findings.

I said “supposedly final" because parents suspecting that their children were affected by Thimerosal in vaccines should request their elected officials to call for another meeting, this one by a new Immunization Safety Review Committee with a different chairperson.

Attorneys who have seen their Thimerosal-autism cases railroaded should also contact VICP (National Vaccine Injury Compensation Program) and “lawyer” as best they can to resume those hearings.

The unfortunate facts

On January 15, 2004, Congressman Dave Weldon, a physician, wrote to then CDC Director Julie L. Gerberding MD, MPH asking her to post-pone the February 9, 2004, Institute of Medicine (IOM) Immunization Safety Review Committee meeting: “Pressing forward with this meeting at this time, I believe, will further undermine the credibility of the Centers for Disease Control (CDC) on matters of vaccine safety and do damage to the reputation of the IOM. I believe the proposed date of this meeting, which you have the ability to change, is in the best interests of no one who is seeking the truth about a possible association between vaccines and neurodevelopmental disorders, including autism"

Dr. Weldon also stated that he was concerned about the agenda of the meeting and the fact that the committee was only dedicating one hour to the MMR/Autism issue and only allowing two witnesses to speak.

The Congressman similarly complained that the “discussion of epidemiology relating to thimerosal and autism is heavily biased against those who have raised these concerns and will not allow for a fair and balanced discussion of the literature. The time set aside for a discussion of the biological mechanisms of thimerosal and autism is inadequate to allow a full discussion of the issue.”

He ended his letter by stating: “To consider two issues of such significance in only seven hours does not serve the public interest. To the outside observer it does not appear to be a serious effort to examine these critical issues. Any conclusions drawn from this meeting, including any report issued, will be viewed as suspect given the very limited time dedicated to examining very incomplete information."

Dr. Gerberding responded that she had shared Dr. Weldon’s concerns with IOM President Fineberg and that the meeting will be held as planned. She wrote: "My own view is that it is extremely important to have the IOM conduct an objective review of emerging data when it has a bearing on vaccine safety as quickly as possible.  In addition, the process should be ongoing at regular intervals, to keep up with this science of vaccine safety as new information becomes available.  We intend to renew our agreement with the IOM to ensure continuation of the safety review process."

Had the conclusions of the IOM been different, i.e., recommending further MMR and Thimerosal – autism research, Dr. Gerberding’s desire to “quickly” review the issue might have been less suspicious. Given the fact that contrary to what she wrote to Dr. Weldon, that the “process should be ongoing”, the committee’s conclusions were quite the opposite, the CDC director’s failure to postpone the meeting was damning indeed.

In addition, everyone including Dr. Weldon knew that the CDC had funded epidemiological studies in Denmark and elsewhere and that some CDC epidemiologists had actively participated and even co-authored some of the publications presented to the committee. Why the CDC ever funded epidemiological studies in Denmark where the pediatric vaccination schedule was different from that of the United States, where fewer vaccines were administered and where Thimerosal had been banned for a decade are questions that just beg to be answered.

Regardless, what no one knew or imagined was that the CDC was also clandestinely ghost-writing, in a fashion, a review of Thimerosal by a US academician and that the IOM committee wanted to see that review before the February 2004 hearing.

To the best of my knowledge, the following information is made public here for the first time. As not to embarrass anyone, I have withheld names.

All the letters were on official CDC stationary with Department of Health and Human Services --- Public Health Service above the CDC logo.

The letters were written by a Senior Advisor to the Director of the National Immunization Program (NIP) of the CDC and addressed to an Assistant Professor at a distinguished university.

July 9, 2003
Dear S.
… Since continuation of the MMR-autism project is probably not needed, there is an alternate approach. There are 6 articles in press and several published dealing with thimerosal and autism. I suggest that we shift emphasis to writing a manuscript that deals with this potential association. I will send you all of the published and in press articles I have so that you can consider this change. Since many of these articles are in press, we will be ahead of the curve if we move rapidly. Another advantage is that with our experience to date and exclusion of the literature validation aspect, this article would be much easier to write.
We should establish a strict timeline for this project. I will be in xxxx on September 21, at which time we can finalize this manuscript, if you agree.

July 10, 2003.
Dear S
Enclosed are several articles dealing with thimerosal and autism. There may be a few more that our vaccine safety folks have. I know of one more ecologic study from Denmark to be published in Pediatrics. I will obtain a copy. Expect a call from me next week to discuss the future.

August 28, 2003
Dear S
Enclosed is the thimerosal manuscript upon which I have made a few edits. In addition there are a few other considerations
1. I just returned from London where I learned that L has submitted a manuscript using data from the UK showing no association between thimerosal and autism. I have contacted L by e-mail to ask for a copy of this manuscript. So we can include it.
2. I suggest adding the table of the Epidemiologic studies.
3. I will inquire as to why Denmark removed thimerosal from the vaccines, and determine if we can obtain information on the 88 patients mentioned on page 13.
4. The introduction dealing with a history of thimerosal should be shortened and moved to the discussion
5. I did not spend time on the references -- next draft
6. I have enclosed a copy of the recent A paper, the IOM report, and another B article.
Good job. Progress is fast and furious.

[Note by FEY: L was a physician attached to the UK Public Health Laboratory Service --- The A paper supported the CDC position and the B paper opposed it]

December 30, 2003
Dear S
Enclosed are several items.
1. A copy of the VAERS article which will appear in xx
2. An edited version of THE manuscript
You have done an excellent job on the manuscript. I am meeting with xxx on Wednesday to discuss this version. I suggest the following:
1. minor edits included
2. move indicated parts of the results section into the discussion section.
3. I know this will be painful for you, but eliminate the part of the discussion dealing with review of the history of thimerosal (22-23)
4. eliminate table 3
5. add a column to table one listing mechanism of ASD diagnosis
6. add the 1985 A animal data to the discussion
7. I will contact Dr. L to ascertain the status of references 38 and 39.
8. I’ll develop a list of people we should ask to review this manuscript before submission
The IOM Safety Review Committee considers autism and vaccines in February and would like a copy of this paper. Therefore we need to submit to a journal before then. The end is near!

The above letters obtained with much difficulty from the CDC through the FOIA show conclusively that the IOM Immunization Safety Review Committee was shown a manuscript on Thimerosal that was commissioned, supervised, corrected and promoted by individuals in the National Immunization Program of the CDC. The letters also show that individuals at the CDC can somehow review articles before they are published in medical journals and can force editors of leading medical journals to accept and fast-track studies they have shaped or created, while on the other hand, their director convenes a meeting pronto in order to railroad contrary findings.

Discussion & Conclusions

Even though the mercury preservative Thimerosal has been added to vaccines since the 1930’s, supposedly to guarantee the sterility of multi-dose vials, no one ever bothered to check its safety or question its use for decades.

The IOM Immunization Safety Review Committee was influenced by the CDC before and during its February 9, 2004 meeting. The committee’s decision concerning Thimerosal and autism was flawed, ill-advised and based on biased epidemiological studies, several of which funded or instigated by the CDC and its National Immunization Program. Moreover its timing was apparently designed to avoid imminent studies which could have demonstrated a connection between vaccines and autism.

Since then, peer-reviewed and published information has clearly indicated:
  • That low doses of Thimerosal such as those in TCV are neurotoxic
  • That such amounts of ethyl mercury possess the potential to affect human neurodevelopment
  • That to date, no studies have been carried out on the neurotoxicity of Thimerosal in the presence of Aluminum-adjuvant presently in some widely used TCV
  • And that exposure to Thimerosal can lead to accumulation of inorganic mercury in the brain
This presentation strongly suggests that the World Health Organization should reconsider its present stand of only recommending TCV in multi-dose vials.

Countries that have the means to buy preservative-free vaccines should ignore the WHO recommendations and do so. The minute added cost of preservative-free single dose vaccines is negligible when compared to the financial and human cost of autism.

HHS should order the Institute of Medicine to create a new Vaccine Safety Review Committee with a new chairperson to review the subject.

The National Vaccine Injury Compensation Program should be requested to ignore the IOM recommendations and to review the presently available information on Thimerosal.

The preponderance of available evidence strongly suggests that Thimerosal containing vaccines could have indeed caused neurological and developmental complications in genetically predisposed infants and children.

In fact, the preponderance of evidence seems overwhelming!


  1. Hornig M, Chian D, Lipkin WI. Neurotoxic effects of postnatal thimerosal are mouse strain dependent. Mol Psychiatry. 2004 Sep;9(9):833-45
  2. Burbacher  TM, Shen DD, Liberato N, Grant KS, Cernichiari E, Clarckson T. Comparison of Blood and Brain Mercury Levels in Infant Monkeys Exposed to Methylmercury or Vaccines Containing Thimerosal
  3. Waly M, Olteanu H, Banerjee R, Choi SW, Mason JB, Parker BS, Sukumar S, Shim S, Sharma A, Benzecry JM, Power-Charnitsky VA, Deth RC. Activation of methionine synthase by insulin-like growth factor-1 and dopamine: a target for neurodevelopmental toxins and thimerosal. Mol Psychiatry. 2004 Apr;9(4):358-70.
  4. James SJ, Slikker W 3rd, Melnyk S, New E, Pogribna M, Jernigan S. Thimerosal neurotoxicity is associated with glutathione depletion: protection with glutathione precursors. Neurotoxicology. 2005 Jan;26(1):1-8.
  5. Geier DA, Geier MR. A comparative evaluation of the effects of MMR immunization and mercury doses from thimerosal-containing childhood vaccines on the population prevalence of autism.Med Sci Monit. 2004 Mar;10(3):PI33-9.
  6. Geier D, Geier MR. Neurodevelopmental disorders following thimerosal-containing childhood immunizations: a follow-up analysis. Int J Toxicol. 2004 Nov-Dec;23(6):369-76.
  7. Geier DA, Geier MR. A two-phased population epidemiological study of the safety of thimerosal-containing vaccines: a follow-up analysis. Med Sci Monit. 2005 Mar 24;11(4):CR160-170
  8. Blaxill MF, L Redwood L, and Bernard S.Thimerosal and autism? A plausible hypothesis that should not be dismissed. Medical Hypotheses; 62: 788-794, 2004.
  9. Humphrey ML, Cole MP, Pendergrass JC, Kiningham KK. Mitochondrial Mediated Thimerosal-Induced Apoptosis in a Human Neuroblastoma Cell Line (SK-N-SH). Neurotoxicology. 2005 Apr 30; (Epub ahead of print)
  10. Parran DK, Barker A, Ehrich M. Effects of Thimerosal on NGF signal transduction and cell death in neuroblastoma cells Toxicol Sci. 2005 Apr 20; (Epub ahead of print)
  11. Havarinasab S, Haggqvist B, Bjorn E, Pollard KM, Hultman P. Immunosuppressive and autoimmune effects of thimerosal in mice. Toxicol Appl Pharmacol. 2005 Apr 15;204(2):109-21.
  12. Ueha-Ishibashi T, Tatsuishi T, Iwase K, Nakao H, Umebayashi C, Nishizaki Y, Nishimura Y, Oyama Y, Hirama S, Okano Y. Property of thimerosal-induced decrease in cellular content of glutathione in rat thymocytes: a flow cytometric study with 5-chloromethylfluorescein diacetate.Toxicol In Vitro. 2004 Oct;18(5):563-9

In Memoriam: Philip B Rudnick PhD ~ December 23, 2010

F. Edward Yazbak MD, FAAP
Falmouth, Massachusetts

Thimerosal Containing Vaccines, Part I - In the Dark by F. Edward Yazbak MD, FAAP

Thimerosal Containing Vaccines, Part II - WHO by F. Edward Yazbak MD, FAAP