Health & Medicine - Posted by Holly Korschun-Emory on Wednesday, January 2, 2013 18:39 - 10 Comments 
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(1 votes, average: 5.00 out of 5) Loading ...Is preservative in vaccines worth the risk?
Although there are clear neurotoxic effects from methyl mercury, dozens of research studies over the past 15 years from countries around the world have failed to yield any evidence of significant harm from ethyl mercury (thimerosal) in the quantities used to preserve vaccines. (Credit: "vaccine and needle" via Shutterstock)
EMORY (US) — Public health experts recommend keeping thimerosal, a commonly used preservative, in the global vaccine supply.
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The text of this article by Futurity is licensed under a Creative Commons Attribution-No Derivatives License.
As part of an international treaty to eliminate controllable mercury pollution and exposure, the United Nations Environmental Program (UNEP) is considering a recommendation to remove thimerosal from all vaccines worldwide. However, the World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE) recently recommended that this part of the ban be removed from the UNEP treaty.
In a commentary in the journal Pediatrics, public health and vaccine experts say removing thimerosal globally has the potential to affect the worldwide vaccine supply and lead to more disease and death.
The authors of the commentary—including Walter A. Orenstein, associate director of the Emory Vaccine Center, and Katherine Seib of the Rollins School of Public Health at Emory University—strongly support the WHO recommendations, contending that many recent studies support the safety of thimerosal in vaccines.
Since the 1930s, thimerosal has been used as a preservative in multi-dose vials of vaccines to prevent contamination from bacteria and fungi, which could be introduced into those vials on repeated entry to withdraw additional doses.
In 1999 the American Academy of Pediatrics and the US Public Health Service recommended moving toward thimerosal-free vaccines as a precautionary measure, and thimerosal has been removed from most vaccines in the US, with the exception of some seasonal influenza vaccines.
This means most US vaccines are now distributed in single-dose rather than multi-dose vials.
Thimerosal is still used as a preservative in resource-poor countries, however, which allows distribution in multi-dose vials. Removing thimerosal as a preservative would result in the use of single-dose vials, which would reduce manufacturing capacity and increase transportation and storage requirements.
Removing thimerosal also would result in the need for increased cold storage capacity that would be unavailable in many areas of the world, a consequence of which may be that non-thimerosal vaccines would compete for space in the cold chain.
Is it safe?
Although there are clear neurotoxic effects from methyl mercury, dozens of research studies over the past 15 years from countries around the world have failed to yield any evidence of significant harm from ethyl mercury (thimerosal) in the quantities used to preserve vaccines, and have consistently supported the safety of thimerosal-containing vaccines, the authors note.
In 2002 the American Academy of Pediatrics retired its 1999 statement after evaluating new research studies showing the lack of adverse effects from thimerosal.
“Had the evidence that is available now been available in 1999, the policy reducing thimerosal use would likely have not been implemented,” the commentary authors write.
“Thimerosal remains an important vaccine preservative in resource-poor countries. Thimerosal allows the use of multiuse vials, which reduce vaccine cost and the demand on already constrained cold-chain systems.
“Even in the United States, thimerosal could be critical for dealing with emergencies and the need to rapidly increase vaccine supply and delivery, such as during a serious pandemic of influenza.
“The continued benefits of thimerosal use in vaccine manufacturing clearly outweigh any perceived risks,” the authors state.
Source: Emory University
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10 Comments
It's ok it's less of a hassle!
“I understand there isn’t sufficient evidence to say thimerosal (ethyl mercury) causes adverse effects in such small amounts, but what about long term exposure of small quantities.”
Well, since ethyl mercury has a half life in the body of less than week, then there is nothing to worry about with regards to bioaccumulation… Unless you give yourself thousands of shots per week, which makes you weird.
PharmaCrit
The often heard argument of the short half life of ethyl mercury in the body has no scientific background. The original study talks about the half-life in the blood (not the body) and does not proof faster excretion from the body. Contrary, in the same study the Hg concentration in the brain was even higher for ethylmercury than for methyl mercury. Since the brain is the target for the neurotoxin, the shorter half life in the blood is not a good sign but even a warning !
“The often heard argument of the short half life of ethyl mercury in the body has no scientific background.”
Oh, really? Your definition of science must be different than mine.
Someone failed their chemistry exam. So sad. So, so sad.
PharmaCrit
So you can cite a scientific study that has proved faster excretion of ethyl mercury from the BODY than for methylmercury ? I haven’t seen that study ! I only know those, who showed the shorter half-life in the circulaiting blood !!! Maybe you do not understand the difference….
Cindy
You write that there are dozens of research studies that “failed to yield any evidence of significant harm from ethyl mercury (thimerosal) in the quantities used to preserve vaccines, and have consistently supported the safety of thimerosal-containing vaccines” — would you please cite those studies?
Rill
“I guess convenience and money outweigh the populations health. Thanks, World Health Organization, for looking out for our health interest and the betterment of humanity. I understand there isn’t sufficient evidence to say thimerosal (ethyl mercury) causes adverse effects in such small amounts, but what about long term exposure of small quantities.”
Yes, it’s SUCH a hassle saving people from death in third world countries. Much better to let them die of demonstrably fatal diseases than give them small doses of a substance that has failed to show any significant level of toxicity. Give me a break. And we’ve been using it for eighty years and have yet to be able to show a danger. How much more long term do you want?
The central thesis of the status quo is horribly and obviously misfounded here. The fact that we currently use a poison for the purposes indicate neither implies nor verifies that is our only option to resolve the multi-use problem. Not by a long shot. Yet, apparently, this fact escapes -professionals in the field-?
Seriously?
Simply stated: we should not introduce neurotoxins to the body intentionally.
Further: The argument’s basis, i.e. that removing thimerosol would cause problems is true if and only if we fail to identify or employ an adequate, preferably non-neurotoxic substitute, which I cannot help but suppose to be well within our current understanding and ability. This means it is also our responsibility to do so, and not to pretend that bizarre arguments about removing toxins from drugs are too costly in their outcome to consider… which is, in fact, plainly stupid.
What about those with methylation defects?
“In 1999 the American Academy of Pediatrics and the US Public Health Service recommended moving toward thimerosal-free vaccines as a precautionary measure, and thimerosal has been removed from most vaccines in the US, with the exception of some seasonal influenza vaccines.”
This is a very good thing for children in the US, and demonstrates that there is some awareness by medical professionals that there is cause for concern.
Very few health professionals know that 30-40% of the population have MTHFR mutations at SNPs 677 and 1298, which causes even small amounts of mercury to bioaccumulate. Children with autism have an even higher incidence of methylation defects, putting them at an even greater risk of complications from vaccines.
Since a significant proportion of the people have methylation defects, we need to consider beneficence. Medical ethics tells us that health care professionals should have the welfare of all patients in mind and always practice beneficence, however we must recognize that all vaccines have potential to harm some of the recipients. If that were not the case, there would be no controversy.
Genetic medicine now lets us know why some people have trouble with vaccines. As we enter a new era of genetic medicine, we will identify more and more questions that need to be answered. There are no clinical trials of vaccines in subjects with known methylation defects, so we can’t generalize safety from old studies to this sub-population of people.
As a nurse, and “part of the herd”, I got my flu shot yearly, even though I developed a pattern of getting sick after the flu shot. Doctors routinely told me that I probably had been exposed to the flu before I got the shot. The last time I got a flu shot (2009) I developed a fever within two hours, and was sick for 3 months. Since then, I learned I have MTHFR mutations at C677T and A1298C (heterozygous at both loci) resulting in ~50% impairment in my methylation ability. Fortunately, I learned of this genetic mutation, and take prescription Deplin to assist methylation in an attempt to bypass my mutation defect. This 61 year old nurse will no longer get the flu shot
Vaccine research needs to begin to address the methylation challenges that affect ~ 1/3 of the population.
Monica
There can never be any justification for using thimerosal/mercury. Always gets back to money/profit at the expense of health.
Methylation needs to work properly otherwise one ends up in trouble. Genetics does come into it.
I wont be having any vaccines whether there is thimerosal/mercury or not.
I guess convenience and money outweigh the populations health. Thanks, World Health Organization, for looking out for our health interest and the betterment of humanity. I understand there isn’t sufficient evidence to say thimerosal (ethyl mercury) causes adverse effects in such small amounts, but what about long term exposure of small quantities.