Ever since there have been vaccines, there has been an antivaccination movement. It began shortly after Edward Jenner discovered how to use the weaker cowpox virus to induce long-lasting immunity to smallpox, there has been resistance to the concept of vaccination, a resistance that continues to this very day. Reasons for this resistance have ranged from religious, to fear of injecting foreign substances, to simple resistance to the government telling people what to do. Some fear even the infitessimally small risk that vaccines pose for the benefit of resistance to disease far more than they fear the diseases themselves, a result of the very success of modern vaccines. Of course, vaccines, like any other medical intervention, are not without risks, making it easy for them to jump on any hint of harm done by vaccines, whether real or imagined, even though vaccines are among the very safest of treatments.

One of the biggest myths that antivaccinationists believe and like to use to stoke the fear of vaccines is the concept that they are full of “toxins.” The myth that mercury in the thimerosal preservative commonly used in vaccines in the U.S. until early 2002 was a major cause of autism is simply the most recent bogeyman used to try to argue that vaccines do more harm than good, as was the scare campaign engineered in response to Andrew Wakefield’s poor science claiming a link between the MMR vaccine and autism. Now that study after study have failed to find or corroborate a link between thimerosal in vaccines or vaccines in general and autism to the point where even the most zealous of zealots are having a hard time defending the claim that mercury in vaccines cause autism any more, predictably the campaign against vaccines has fallen back on the old “toxins” myth. If you peruse antivaccinationist websites, it won’t take long to find articles claiming that vaccines are full of the most terrifying and nasty toxins. Examples in the media abound as well. For example, Jenny McCarthy, comic actress and former Playboy Playmate who has been doing the talk show and publicity circuit lately to plug her book in which she claims that vaccines caused her son’s autism and that she was able to cure it with “biomedical” interventions and diet, recently gave an interview in which she said:

What I really am is “anti-toxins” in the vaccines. I do believe that there is a correlation between vaccinations and autism. I don’t think it’s the sole cause, but I think they’re triggering–it’s triggering–autism in these kids. A really great example is…is, sometimes obesity can trigger diabetes. I do believe that vaccines can trigger autism…It’s so much more than just mercury. That is one ingredient in the recipe of autism…I’m talking about all of them. I’m calling for cleaning out the toxins. People don’t realize that there is aluminum, ether, antifreeze, still mercury, in the shots…People are afraid of secondhand smoke, but they’re OK with injecting the second worst neurotoxin on the planet in newborns.

Another example of what I sometimes call the “toxin gambit” comes from Deirdre Imus, wife of shock jock Don Imus, with both husband and wife being well-known and reliable media boosters of the claim that vaccines somehow cause autism:

So, where are the evidenced based (conflict free) studies that prove the safety of these “trace” amounts and proof that there are “no biological effects” of any amount of mercury being injected into our children and pregnant moms? Also, where are the evidence based studies proving the safety of vaccines given to pregnant moms and our children that contain other toxins such as aluminum and formaldehyde?

The most recent example of this tactic comes from an organization called Generation Rescue, which just last week ran a full-page ad in USA Today, paid for in part by Jenny McCarthy and her present boyfriend Jim Carrey:


Besides being one of the most egregious examples of a post hoc ergo propter hoc fallacy that I’ve ever seen from an antivaccination site, this Generation Rescue ad demonstrates clearly a new strategy (or, more properly, a resurrection of an old technique) now that science is coming down conclusively against mercury in vaccines as a cause of autism, a strategy of propagating fear by linking vaccines with “toxins.” So what’s the real story? Are there really deadly toxins in vaccines that parents should be worried about?

To answer this question, I thought I’d use what to me is arguably the most amazingly over-the-top examples of this strategy of listing “toxins” in vaccines as a jumping off point. This example is embodied in a post by one Kent Heckenlively writing for the Age of Autism blog entitled FDA Says A-OK: Vaccine Ingredients from A to Z. This post examines a list taken straight from the CDC website of ingredients found in vaccines besides the bacterial or viral proteins designed to evoke the protective immune response and tries to scare parents about almost every one. Of course, nearly all of these comparisons fail to acknowledge that time-honored pharmacological principle that “the dose makes the poison” and extrapolate horrible consequences known to occur during prolonged exposure or exposure to large amounts to the tiny amounts in vaccines. That’s exactly what Mr. Heckenlively does to what is, I must say, a truly ridiculous level. However, as patently ridiculous as Mr. Heckenlively’s post is, I believe that it is not a straw man and still worth starting the discussion with because it serves almost as a reductio ad absurdum concentration of actual arguments that antivaccinationists make about “toxins” in vaccines. A few examples, starting with these, will readily show you what I mean:

Neomycin is used as an anti-bacterial. It is also nephrotoxic and can cause kidney damage.


Polymyxin B is used as an anti-bacterial. It binds to the cell membrane and alters its structure, making it more permeable. The resulting water uptake leads to cell death. Side effects include neurotoxicity and acute renal tubular necrosis.


Streptomycin is used as an anti-bacterial. Streptomycin stops bacterial growth by damaging cell membranes and inhibiting protein synthesis. Specifically, it binds to the 16S rRNA of the bacterial ribosome, interfering with the binding of formyl-methionyl-tRNA to the 30S subunit. This prevents initiation of protein synthesis. Humans have structurally different ribosomes from bacteria, thereby allowing the selectivity of this antibiotic for bacteria. Streptomycin cannot be given orally, but must be administered by regular intramuscular injection. An adverse effect of this medicine is oto-toxicity. It can result in permanent hearing loss.

All of this is true but highly deceptive. Why? The recommended dosage of streptomycin for the treatment of various infections is 20-40 mg/kg per day, for a maximum of 1 g per day! Why is this relevant? Because every vaccine given to a child during his entire life probably doesn’t even come anywhere near 1 mg, that’s why. Antibiotics like streptomycin and neomycin are used in cell culture medium at low concentrations to suppress the growth of bacteria. The reason that these antibiotics are listed is because they’re used in culturing the cells necessary to grow the viruses used in making vaccines. By the time the vaccine is made, these antibiotics are only present in trace amounts, nowhere near enough to cause renal toxicity or ototoxicity, which only occurs with use at or above the range of the doses listed above. I suspect that Mr. Heckenlively knows this too but only mentions it because he knows it will scare parents. Indeed, he takes this sort of distortion to a truly comical extreme with this example:

Sucrose is used as a stabilizer. Over-consumption of sucrose has been linked with some adverse health effects. The most common is dental caries or tooth decay, in which oral bacteria convert sugars (including sucrose) from food into acids that attack tooth enamel. When a large amount of foods that contain a high percentage of sucrose is consumed, beneficial nutrients can be displaced from the diet, which can contribute to an increased risk for chronic disease. It has been suggested that sucrose-containing drinks may be linked to the development of obesity and insulin resistance.

Does Heckenlively honestly think that the baby is eating the vaccine or that there’s kilogram upon kilogram of sucrose in vaccines? Using Mr. Heckenlively’s logic, I could say that because there’s the chelation agent EDTA used in some vaccines as a preservative babies could use it as a treatment for heavy metal poisoning. Sadly, Mr. Heckenlively is not alone in using such distortions to attack vaccines. For example, here are some even more deceptive statements on other such antivaccinationist lists as well about other vaccine ingredients:

Sodium Hydroxide (also known as lye, caustic soda, soda lye.) Is corrosive and is an Eye, skin and respiratory irritant. Can burn eyes, skin and internal organs. Can cause lung and tissue damage, blindness and can be fatal if swallowed. Found in oven cleaners, tub and tile cleaners, toilet bowl cleaners and drain openers.


Hydrochloric acid: CAN DISTROY TISSUE UPON DIRECT CONTACT! Found in aluminum cleaners and rust removers.

Neglected is the simple chemical observation that these effects depend upon the pH of these acids and bases. The reason they’re used in vaccines is to adjust the pH of the vaccine to neutral. The person who wrote these things clearly doesn’t understand the basic concept of pH. Does she honestly think that the pH of vaccines is either 0 (very acid) or 14 (very basic)? Moreover, sodium hydroxide, when it neutralizes an aqueous acid solution will simply form the sodium salt of whatever the anion was in the acid. Hydrochloric acid will form the chloride salt with whatever cation was in the base. When sodium hydroxide or hydrochloric acid are used, one to neutralize the other, the result is an NaCl solution of neutral pH: common table salt.

Of course, this list does contain a number of chemicals that do sound really scary. However, if you remember the pharmacological principle that “the dose makes the poison,” they are much less so. These chemicals are all present at extremely low concentrations in vaccines, certainly not at any dangerous levels. Moreover, some of the fearmongering about such seemingly scary toxins betrays a serious lack of understanding of basic chemistry.

Here’s one example. The aforementioned Jenny McCarthy has been repeating that there is “antifreeze” in vaccines, as she did in the interview linked to earlier. That line is straight off of a number of antivaccination websites. (Amazingly Mr. Heckenlively managed to restrain himself from repeating “the “antifreeze in vaccines” gambit. I can only hope that it is due to intellectual honesty, although I can’t rule out the possibility that he just didn’t know about it.) One website in particular links to an MSDS about Quaker State Antifreeze/Coolant, the principal ingredients of which are ethylene glycol and diethylene glycol. Guess what? There’s no ethylene or diethylene glycol in vaccines. Accurate chemistry or pharmacology never was a major concern among antivaccinationists. After all, Jenny McCarthy also says that there’s “ether” in vaccines, too. The only “ether” I could find in the CDC’s list is polyethylene glycol pisooctylphenyl ether (Triton X-100), a common detergent agent used to make cell membranes permeable. In the past, a compound called Tween-Ether was sometimes used instead of Triton X-100; it’s the same sort of thing, a fairly large organic molecule with an ether chemical group hooked on. I suspect that Jenny and most antivaccinationists are too chemistry-challenged to realize that this is not the same thing as diethyl ether, which was used as an anaesthetic agent before safer volatile agents were developed and is often commonly referred to as just “ether.” Jenny also apparently doesn’t realize that ether is not very soluble in aqueous solution. The only way I could even conceive ether being used in the vaccine manufacturing process is if it’s used for a chemical extraction, in which case, it too would be present in at best trace amounts. Moreover, this may even be one source of the claim that antifreeze is in vaccines as well. Note the first part of the chemical name: “polyethylene glycol.” It just so turns out that a major component of many antifreezes is the chemical ethylene glycol.

I also suspect that the whole “antifreeze in vaccines” canard may have derived from a claim that ethylene glycol is used in the synthesis of thimerosal. In actuality, it’s synthesized using ethyl mercuric chloride, thiosalicylic acid, sodium hydroxide and ethanol, although I don’t know if there are other methods of synthesis that do involve ethylene glycol. The origin of this claim could also come from other trace chemicals in vaccines as well, such as propylene glycol. Either way, even if there were ethylene glycol in vaccines, it would not be at a concentration anywhere near high enough to be toxic or dangerous.

Because mercury hasn’t been in most childhood vaccines for six years, one of the two most favored ingredients that antivaccinationists now like to cite is formaldehyde. Yes, that is indeed the same chemical that’s used to fix tissue for pathology (usually as a 10% solution known as formalin that contains 10 g/100 ml of formaldehyde and is buffered to a neutral pH) and the same chemical used in the embalming fluid for the cadavers we dissected as medical students. (Indeed, I still remember that smell, which was impossible to get rid of entirely during the months I took gross anatomy.) During the vaccine manufacturing process, it’s used to inactivate live virus, and traces do remain after manufacturing. Why on earth would those traces be allowed to remain? Remember again: The dose makes the poison. In trace amounts, formaldehyde is not dangerous. Also, it doesn’t last long in aqueous solution, such as vaccines. It breaks down to formic acid and carbon monoxide. Moreover, exposure to far more formaldehyde than any vaccine contains is ubiquitous in modern life. It’s in auto exhaust, and various substances found in virtually every household emit it:

Latex paint, fingernail hardener, and fingernail polish release a large amount of formaldehyde to the air. Plywood and particle board, as well as furniture and cabinets made from them, fiberglass products, new carpets, decorative laminates, and some permanent press fabrics give off a moderate amount of formaldehyde. Some paper products, such as grocery bags and paper towels, give off small amounts of formaldehyde. Because these products contain formaldehyde, you may also be exposed on the skin by touching or coming in direct contact with them. You may also be exposed to small amounts of formaldehyde in the food you eat. You are not likely to be exposed to formaldehyde in the water you drink because it does not last a long time in water.

Of course, given my background, it’s hard not to mention that every generation of medical students since time immemorial has been exposed to large amounts of formaldehyde. I’m not saying this is a good thing; personally I wish I could have avoided it, and it would be a good thing if we could decrease the average exposure to it while going about our activities of life. However, it’s a matter of perspective. Antivaccinationists rant about formaldehyde in vaccines and ignore a source that is orders of magnitude greater over the lifetimes of each and every one of us from childhood to old age: the environment.

Finally, now that thimerosal has been removed from nearly all childhood vaccines, the antivaccinationists needed to find another bogeyman in vaccines to demonize, and, given their fear of heavy metals and belief that chelation therapy to remove them can cure autism, the most obvious candidate was aluminum, which has been used as an adjuvant in many vaccines for over 80 years to increase the ability of antigens to provoke the desired immune response. It has become other of the top two chemicals that antivaccinationists like to cite to demonize vaccines. True, aluminum is not nearly as scary-sounding as mercury, but with mercury falling by the wayside, antivaccinationists are certainly trying very hard to make it so, which brings us back to Mr. Heckenlively’s post:

Aluminum hydroxide, aluminum phosphate, and aluminum potassium sulfate are all used as adjuvants to stimulate the immune system. Aluminum products found in commercial antiperspirants have been linked with breast cancer. A recent article published in the Journal of Inorganic Chemistry based on research from Keele University in England was trying to explain the “known, but unaccounted for, higher incidence of tumors in the upper outer quadrant of the breast.” They found that aluminum content was higher in the outer regions where there would be the highest density of antiperspirant. In discussing aluminum’s potential danger the report stated, “Aluminum is a metalloestrogen, it is genotoxic, is bound by DNA and has been shown to be carcinogenic. It is also a pro-oxidant and this unusual property might provide a mechanistic basis for any putative carcinogenicity. The confirmed presence of aluminum in breast tissue biopsies highlights its potential as a possible factor in the etiology of breast cancer.”

I can’t help but ask here: Applying an aluminum-based compound to one’s skin over the course of many, many years is related to some injections of aluminum-based adjuvants in vaccines exactly…how? Of course, the above claim is a total nonsequitur, but what about the frequent confident claims on antivaccination websites that aluminum causes Alzheimer’s disease and that by implication vaccines cause Alzheimer’s? This is a claim by well-known antivaccinationist Hugh Fudenberg, who is often quoted thusly:

According to Hugh Fudenberg, MD (, the world’s leading immunogeneticist and 13th most quoted biologist of our times (nearly 850 papers in peer review journals), if an individual has had five consecutive flu shots between 1970 and 1980 (the years studied) his/her chances of getting Alzheimer’s Disease is ten times higher than if they had one, two or no shots. I asked Dr. Fudenberg why this was so and he said it was due to the mercury and aluminum that is in every flu shot (and most childhood shots). The gradual mercury and aluminum buildup in the brain causes cognitive dysfunction. Is that why Alzheimer’s is expected to quadruple? Notes: Recorded from Dr. Fudenberg’s speech at the NVIC International Vaccine Conference, Arlington, VA September, 1997. Quoted with permission. Alzheimer’s to quadruple statement is from John’s Hopkins Newsletter Nov 1998.

Not surprisingly, this claim is not supported by science. There’s no good evidence that the flu vaccine is associated with an increased incidence of Alzheimer’s. Indeed, on his personal blog, my co-blogger Steve Novella has nicely summarized the evidence regarding whether or not aluminum is involved in the pathogenesis of Alzheimer’s disease, concluding:

The evidence of aluminum and AD is mixed, without a clear direction. At present the best answer we have is that aluminum probably does not cause AD but appears to be playing some role, perhaps influencing severity. But even after 42 years, there remains a question mark next to these conclusions. We can rule out that aluminum is the single cause of AD, but whether or not it is an independent risk factor is a qualified “probably not.”

And, most importantly, Steve said this about how the science looking at whether aluminum causes Alzheimer’s disease or not is abused:

The mainstream scientific and patient or disease-oriented groups accurately reflect the above interpretation of the research. But the complexity of the results make it very easy to exploit for the purpose of fear-mongering. The notorious crank website,, for example, cherry picks the evidence that suggests there is a correlation and piles it up to present a very distorted view of the issue. There will likely persist rumors, scare e-mails, and conspiracy websites promoting the idea that aluminum causes AD regardless of how the research progresses.

Now the antivaccinationists are climbing aboard the aluminum scare train as well because the scientific evidence is becoming so clear that their previous favorite bogeyman vaccine ingredient, thimerosal, is not associated with autism that even the die-hards are having a hard time arguing that it is anymore, particularly now that thimerosal is no longer present above trace amounts in most childhood vaccines. Consequently, they have no choice but to branch out to other scary-sounding ingredients in vaccines and invoking vague (and, conveniently enough, almost impossible to demonstrate) “environmental toxins” or risk becoming irrelevant.

One thing that you have to remember about resistance to vaccines by groups like Generation Rescue, SafeMinds, and others is that it is not scientific in nature. It is either due to an excessive reliance on anecdotes or confusing correlation with causation (usually with a distrust of science and medicine), or it is ideological in nature. No matter how many of the “toxins” scientists remove from vaccines, it will never be enough for Generation Rescue, Jenny McCarthy, or other antivaccinationists, because it’s all about the vaccines and the very concept of vaccination itself, not any individual ingredients in the vaccines. Antivaccinationists will never come to a point where they say, “OK, now I believe that all the toxins are gone and vaccines are safe.” They’ll either fixate on the viruses or the viral or bacterial antigens themselves, or they’ll make the claim that vaccines are made using “aborted fetuses” because some cell lines used to grow up virus stocks were derived from aborted fetuses 40 or more years ago. If every trace of formaldehyde, aluminum, or any other chemical with more than two syllables in its name were somehow to be removed from all vaccines, they would still be saying things like this:

It is the toxin, or germ, contained in the shot itself that causes the adverse affects on the immune system.

Dead-virus, or live-virus vaccine etc…who cares? The cultures for polio vaccines are grown in the kidney tissue of dead monkeys in third-world countries with little or no controls and the virulent pustule toxin is put in vaccines to be shot into you little kid’s arm. I wouldn’t go into a room where that putrid stuff is, let alone inject it into my blood stream! Would you?

Here’s an even more ridiculous example:

This DNA is from such organisms as various animals, animal/human viruses, fungi and bacteria. It has been documented that the injecting foreign DNA can cause it or some of it to be incorporated into the recipient’s DNA (see ‘Immunisation’ Against Diseases for Children). Remember, nature has not experienced such a direct invasion as this before, so can you be sure that it would have developed a way to protect your body against it?

That pretty much rules out any live attenuated virus vaccine for such an antivaccinationist, doesn’t it? Even worse is this:

The human blood is supposed to be, and traditionally was, sterile – no bacteria (or other organisms) present in it. That is not the case any more. Naturally this has a weakening effect on the immune system, apart from sometimes leading to severe bacterial infections.

No live bacteria is in a vaccine. It is possible, as with any injection, for vaccines to become contaminated with bacteria (which is one reason why preservatives like thimerosal were used for multidose vials, where reuse increases the risk of bacterial contamination), but that is not the intent. What is in vaccines are bacterial proteins, which contain the antigens necessary to provoke the desired immune response.

It would be fascinating to engage an antivaccinationist who makes the claim that he is not “antivaccine” but “antitoxin” or “pro-vaccine safety” in a discussion and ask him this hypothetical question: If formaldehyde, “antifreeze,” aluminum, thimerosal, and every chemical in vaccines circulating in all those lists on antivaccination websites that so frighten you were somehow absolutely removed from the standard childhood vaccines so that not a single molecular remained, would you then vaccinate your child? The only thing that would remain is buffered salt water and the necessary antigens, be they killed virus or bacterial proteins, or whatever.

My guess is that nearly all antivaccinationists would say no, because it’s the “toxin” that makes vaccines work that really disturbs them, as the quotes above clearly demonstrate. Remember that when you see these lists circulating on antivaccinist websites. Remember, too, the principle that the dose makes the poison. Only then will you understand how toxic the myths about vaccines being peddled by antivaccinationists are.



Posted by David Gorski

Dr. Gorski's full information can be found here, along with information for patients. David H. Gorski, MD, PhD, FACS is a surgical oncologist at the Barbara Ann Karmanos Cancer Institute specializing in breast cancer surgery, where he also serves as the American College of Surgeons Committee on Cancer Liaison Physician as well as an Associate Professor of Surgery and member of the faculty of the Graduate Program in Cancer Biology at Wayne State University. If you are a potential patient and found this page through a Google search, please check out Dr. Gorski's biographical information, disclaimers regarding his writings, and notice to patients here.