Vaccine Ingredients

Do vaccines really contain the horrifying poisons claimed by antivaccine activists?

by Brian Dunning

Filed under Alternative Medicine, Conspiracies, General Science, Health

Skeptoid #180
November 17, 2009
Podcast transcript | Listen | Subscribe
Also available in Chinese | Russian

Today we're going to point our skeptical eye at some of the claims made by antivaccine activists, in particular, their lists of frightening chemicals and other dangerous toxins they say are included in vaccines. As it's an important topic and is increasingly in the public eye, we don't want to dismiss these claims out of hand. Rather, we want to have a handy working knowledge of the basics so we're better prepared to deal with such rhetoric when it comes up.

You don't have to go to the antivaccine web sites to find this horrifying list of witch's-brew ingredients. The Centers for Disease Control publishes a detailed list of every additive in every vaccine, sorted both by ingredient and by vaccine. I run my eye down this official list: formaldehyde, aluminum phosphate, ammonium sulfate, bovine extract, thimerosal, amino acids, even monkey kidney tissue. This list is published by the very same government that's assuring us these vaccines are safe. How can that be? Does this mean the antivaccine activists are right, and vaccines are indeed loaded with deadly toxins?

This is a case where cooler heads need to prevail. First, let's start with the premise that every cell of your body is made up of a huge number of chemical compounds, all of which have scary-sounding chemical names. Therefore, we can derive that scary-sounding chemical names, by themselves, are not to be feared. Cooler heads might choose to allow for the possibility that these scary chemicals are added to vaccines because they serve some useful purpose.

When you're exposed to a pathogen, it irritates your body. This irritation is what provokes your immune system to respond, and produce antibodies to fight the pathogen. Vaccines work the same way. They simulate the pathogen in order to produce to right irritation. To prepare your body with the right antibodies to fight some anticipated future pathogen, it's a necessary and expected step for the vaccine to provoke your immune system with a carefully planned challenge. So when you hear antivaxxers charge that vaccines are harmful and irritating, that's quite true, but it's for an important reason and it's very deliberately controlled. This attack on your body to provoke an immunological response is the way vaccines work. It's the way your immune system rolls. You don't strengthen your immune system by eating vitamins or drinking wheatgrass juice or doing yoga or having a coffee enema; you strengthen it by challenging it to respond.

So now that we understand that a vaccine is not pretending to be a shot of Mickey Mouse sunshine, let's take a look at some of these frightening sounding ingredients:


Absolutely true. Formaldehyde sounds scary because we see dead animals preserved in jars of it in museums. One of its uses is to sterilize things, and this is why small drops of it are added to some vaccines. Without such sterilization, a vial of vaccine might become contaminated while it's sitting on the shelf. Formaldehyde is used because it's naturally found in the human body, as it's a normal byproduct of digestion and metabolism. When you receive a vaccine shot that was sterilized with formaldehyde, you already have much more of it in your body than you get from the shot. All of this formaldehyde is easily broken down chemically simply because your body is an aqueous environment, and it's harmlessly discharged every day.


This one is simply untrue. Antifreeze, the poisonous substance used in your car's engine, is ethylene glycol. Because it's so poisonous, antifreeze is not used in food processing or medical equipment, and certainly not in vaccines or other drugs. A less toxic form of antifreeze is propylene glycol, which is not in vaccines either. What is used in some is 2-phenoxyethanol. It's an antibacterial agent used in many vaccines to sterilize them, and also used in wound care as a topical antibacterial. The confusion with antifreeze probably comes from the fact that both are part of the glycol ether family of hydrocarbons, but they are not the same thing.


This is the most common claim, and it's the one you've probably heard the most about, so I won't spend much time on it. Some vaccines (but no scheduled childhood vaccines) are preserved with thimerosal, which contains ethylmercury. Elemental mercury is a dangerous neurotoxin, but when it's bound as an organic ethyl, it's easily filtered out of your body by your kidneys and is quickly discharged. This is one reason thimerosal has always been such a safe and popular preservative, and it's still found in many products. Mercury can also be bound as a methyl, which is different, and is much harder for your body to filter out. But fear not; no vaccines or thimerosal ever contained methylmercury, and this scaremongering has no plausible foundation.

Latex Rubber

This one is also completely untrue. Latex is not, in any way, part of any vaccine, and never has been. The source of this claim is the fact that a lot of medical equipment, like syringes and packages, contain latex. Alternatives are always available for people with severe latex allergies. This is a common issue for such people, and has no specific relevance to vaccines whatsoever.

Hydrochloric Acid

Scary sounding, and true. If you pour hydrochloric acid on your skin, you get burned, because your skin is pH balanced. But if you add acid to something that's alkaline, acid brings it back into balance. Hydrochloric acid is used in many industries to bring compounds that are too alkaline to the desired pH level, and the pharmaceutical industry is no different. Some vaccines, once the active ingredients are all added, may be too alkaline; and if injected like that, would cause an adverse reaction. Hydrochloric acid brings the vaccine down to your body's normal pH level of about 7.4. Hydrochloric acid is also the primary digestive acid produced in your stomach, so it's no stranger to the human body.


Aluminum, in various forms, is added to vaccines as an adjuvant. An adjuvant is like a catalyst for the desired irritation, making the challenge even more annoying for your body. It's supposed to be there, on purpose, to make your body react even more strongly. More antibodies are created as a result of the more provocative challenge. Remember: Mickey Mouse sunshine and roses do nothing.

Aluminum is, of course, a neurotoxin, but only at amounts far, far higher than that normally found in our bodies, in the environment, and certainly in vaccines. Just by living and breathing on a planet like Earth where aluminum is the third most abundant element, the average person consumes 3-8mg of aluminum per day, of which less than 1 percent is absorbed into the blood. Vaccine doses are allowed to contain a maximum of .85mg of aluminum; so the maximum dose of aluminum in a vaccine is about the same as the maximum that might get into everyone's blood in a normal day (about what's contained in 33 ounces of infant formula). Most vaccines contain less than this. Studies have proven no difference in neurological condition between children who have had aluminum adjutated vaccines and those who have not.


Once again: FAIL. Completely untrue. Although any search of the web would have you believe otherwise: The phrase "aspartame in vaccines" is all over Google. So what are these vaccines? I searched the CDC's database of vaccines; nothing. I searched the database of additives; still nothing. I only found only antivax article that mentioned specifically which vaccine aspartame is in, and it claimed only one: The typhoid vaccine Typhim Vi. But it's not true. The additives in Typhim Vi are publicly available and aspartame is not on the list. This is when the antivaxxers are at their worst, when they simply make up lies. This is not constructive for any purpose.

Aborted Fetal Tissue

They sure picked the scariest sounding thing they could think of here! Although this specific ingredient is made up, vaccines can include all sorts of proteins derived from all sorts of animals.

Human Serum Albumin, or HSA, is a stabilizing protein made from human blood donations, not from aborted fetuses. Bovine albumin is also used in a few vaccines. Some vaccines are grown in cultures of monkey or chicken kidney tissue, and when the vaccines are extracted, a few cells from the culture always remain. There's never been any evidence that this might be dangerous. Some vaccines are cultured inside chicken eggs, and some egg protein may remain as a result. This can be a problem for people with severe allergies to egg protein, so these people should avoid these vaccines.

Tip Skeptoid $2/mo $5/mo $10/mo One time

You'll hear all sorts of shock stories about embryonic fluid and cells of exotic animals. Be skeptical of such stories, and you are shocked and concerned, spend five minutes searching the web to find out if that ingredient is actually used; and if so, why; and whether it represents any credible cause for concern. I guarantee you that Jenny McCarthy is neither the first person, nor the best informed, to have considered vaccine safety.

Live Viruses

Some viruses don't retain their chemical markers well enough when they're dead in order for the immune system to recognize them, so a very few vaccines are given with the viruses still alive. Formaldehyde is usually used to knock them out, weakening them to the point where they no longer pose a threat, but still alive enough to provoke the desired response. This is not done haphazardly: Finding just the right balance for the vaccine to be effective but not dangerous is hard work.

You'll hear antivaccine activists shout "Green our vaccines!" What do they mean? Are vaccines environmentally unfriendly? What does "being green" have to do with it? Presumably this is a swipe at vaccine additives which they believe are unsafe or damaging to the environment. Sadly it's too vague of a charge to answer directly. Specific claims can be tested; vague rallying cries cannot. This is where the antivaxxers' movement has taken them: Whenever they've attempted to levy a specific, testable claim, it's easily falsified. Don't let a sound byte as meaningless as "Green our vaccines" carry any clout it has not earned.

Many antivaccine activists believe that a healthy diet is all that's needed to guard against disease. Unfortunately, a healthy diet by itself does not present any immunological challenges. No antibodies are created as a result. Then when a pathogen enters the body, the pathogen wins, and the body becomes diseased. If you focus on your diet or your fitness, but ignore your immune system, expect to look slim and run marathons, but don't expect your immune system to be well prepared should you be unlucky enough to run into polio.

Brian Dunning

© 2009 Skeptoid Media Copyright information

References & Further Reading

AAP. "Vaccine Ingredients." Immunization. American Academy of Pediatrics, 20 Jan. 2011. Web. 25 May. 2011. <>

CDC. "Ingredients of Vaccines - Fact Sheet." CDC. U. S. Federal Government, 19 May 2009. Web. 11 Feb. 2010. <>

Janeway, C., Travers, P., Walport, M., Shlomchik, M.J. Immunobiology. New York: Garland Publishing, 2001. 582-583.

Marshall, Gary. The Vaccine Handbook. West Islip: Professional Communications, Inc., 2008.

Ragupathi G., Yeung K., Leung P., Lee M., Lau C., Vickers A., Hood C., Deng G., Cheung N., Cassileth B., Livingston P. "Evaluation of widely consumed botanicals as immunological adjuvants." Vaccine. 2 Sep. 2008, 26(37): 4860-4865.

Ribeiro C., Schijns V. "Immunology of vaccine adjuvants." Methods Molecular Biology. 1 Jan. 2010, 626: 1-14.

Reference this article:
Dunning, B. "Vaccine Ingredients." Skeptoid Podcast. Skeptoid Media, 17 Nov 2009. Web. 13 Oct 2015. <>


10 most recent comments | Show all 195 comments

The CDC isn't the only organization overseeing common vaccines. Vaccines for Polio, Smallpox, etc. have been used around the world successfully for several DECADES. The Smallpox vaccine has been around since 1796! Now the disease has been eradicated. Vaccination isn't some new, untested, experiment being conducted by an isolated group, or even an isolated government.

But if you'd prefer this...

This all reminds me of back in the day when people complained about mandatory seat-belt laws and they tried to argue that you're better off being thrown clear of the accident.

Jeff, Toronto
September 23, 2013 11:34pm

Thank you Jeff.
I went to the link you attached from Wikipedia, and I guess you are referencing to it to show a picture of a child with small pox in 1973 before it was declared eradicated in 1977. And I should have been more specific. I am NOT against vaccinations. I just DON'T TRUST that the U.S in which I live, is an honest government in regards to giving 100% truthful information. There has been many whistle blowing situations in the U.S to back up my reasons for feeling this way. All I am asking for is for studies regarding vaccinations outside of government based test (from the U.S) and personal scientific breakdowns of vaccines referenced from the info given by the CDC. Does anyone have links that give info from privatized studies from other countries or independent groups, so I can cross reference for myself? From there, I would like to draw my own conclusion about vaccinations given in present day. A lot has changed in terms of how our country is ran, since the 1970's. Just look at how much the food industry has changed. The quality of food and how it's grown has drastically changed for the worst if you ask me. So referencing a picture about small pox being eradicated in Bangladesh in 1977 still isn't helping me with my dilemma.

Gina, San Francisco, CA
September 26, 2013 2:40pm

"You don't strengthen your immune system by eating vitamins or drinking wheatgrass juice or doing yoga or having a coffee enema; you strengthen it by challenging it to respond."?

Yes you DO strengthen your immune system by eating correctly, practicing good hygiene, & taking good care of your body . Vitamins & minerals are part of that, & essential to the health & function of your body. What DOESN'T strengthen your body is injecting the chemicals & antigens in your article & expecting your body to "magically" be immune. That is inept. Naturally occurring antigens are plentiful enough.

Antibody response to vaccines was proven to not equate to immunity way back in the 1940's. You bypass the normal route of building immunity by injecting toxins directly into the blood. Vaccines "slam" the immune system into action with squalene, thimerosal, & other adjuvants unnecessary to building HEALTH. Why bypass the secretory IGA in your nasal passages & digestive system which is the 1st line of defense? The answer? Because it is profitable to sell vaccines. PERIOD.

Let me ask you this - why vaccinate for Diptheria, Pertussis, &Tetanus when they are toxin-mediated diseases? Profits, perhaps?

The digestive system is estimated to be roughly 80% of your immune system, it makes sense that eating well & keeping your body healthy with exercise, proper sleep, & stress reduction, such as yoga.

Disease #'s began to fall rapidly after education & hygiene, not from vaccine introduction.

Jason, Arizona
September 28, 2013 4:25pm

I am surprised Gina. You'd let private industry review itself rather than regulatory authorities?

Jason, thats starting to look like a bit of a question begging style..

Minke Drain, Sin City Oz
October 3, 2013 2:26pm

You can call it what you want, but I would simply like an honest answer to the question. Begging the questions is not the same as raising the question, which is what I feel I did. Since it is the toxin found in Diptheria, Pertussis & Tetanus that happens to be the causative agent in those diseases, why is there a reason to vaccinate against the bacteria? This is from

"In spite of high vaccination rates, the number of cases of pertussis in the United States has increased steadily since the 1980s (39). Bordetella pertussis, the causative agent of whooping cough, is a gram-negative bacterium that remains localized to the respiratory tract throughout infection. However, systemic effects of the infection, such as lymphocytosis, demonstrate a toxin-mediated component of the disease".

So, do vaccines prevent toxin-mediated components of disease? Is this begging the question?

While we are are on the subject, when would anyone in a normal setting actually encounter Diptheria, pertussis, &Tetanus all at the same time? Yet the vaccine makers combine all 3 in one vaccine. Why is this? It is to maximize cost-effectiveness. PERIOD.

Gina brings up some very good points, & I, too, am very skeptical of anything that is mandated on the public under the guise of "public health" when profit is driving the movement. Nowhere did I happen to read where she said "I'd let private industry review itself rather than regulatory authorities". Did I miss something

Jason, Arizona
October 9, 2013 7:23pm

Aluminium studies - there is no reference list of the 35 reports, Im not sure about confidence intervals of the latter two results, and I don't like the statement 'Despite a lack of good-quality evidence we do not recommend that any further research on this topic is undertaken.'

Veronika, London
January 15, 2014 4:54am

The statement says that researching it is useless because, despite the lack of solid evidence, they are next-to-certain that aluminium does the job in the way it is supposed to.

Tetanus is encountered with badly prepared food and water, as is diptheria and pertussis.

Bill, Canberra
February 9, 2014 2:37am

Gina and Jason,

I doubt that I will ever convince you of anything but I will give it a try. There is a long strand of distrust in the government in the U.S. and it isn't necessarily a bad thing. But there is a world of difference between "free people have rights that government should not infringe" and "the government is trying to kill me."

If they were trying to kill you or perform "population control" - they would not do so via vaccine injections that *provably* save millions of lives. As truly oppressive governments throughout history have proven repeatedly, there are much more efficient means of "reducing" the population.

And Jason, you say: "Yes you DO strengthen your immune system by eating correctly, practicing good hygiene, & taking good care of your body." This is true only to the extent that a healthy, well-maintained body will have a normal healthy immune system. That is, it will be better than someone who suffers from a poor diet, etc. But there is no magic here: a "normal, healthy" immune system cannot prevent you from getting polio, diptheria, etc. and, if it does fight it off, does so at great cost.

"What DOESN'T strengthen your body is injecting the chemicals & antigens in your article & expecting your body to "magically" be immune." don't "do" science I see. That is the WHOLE POINT, Jason. It isn't "magic" at all - it is the careful application of decades of scientific research to the biochemistry of disease.

MarkB, New Jersey
March 24, 2014 7:03am

I started to like the looks of this website & was anxious to hear "the real goods". Until I listened to this one about vaccines. The loud echoes used for effect when describing a word or term or belief that is not the belief of this website.......combined with name dropping (Jenny McCarthy) really turned me off. These guys are as much about pushing their position in a theatrical forum as anyone else. It loses credibility. One word - Bye!

Shell, Canada
October 5, 2014 8:57am

You said: "studies have proven no difference in neurological condition between children who have had aluminum adjutated vaccines and those who have not."

There in lays the problem. The studies were conducted by the manufacturers and not an independent. They used aluminium in BOTH the vaccine and the Placebo so that side effects (there were!) were the same in both groups. - thus drawing the conclusion that there was no problem. Sounds strange. Indeed. check it out.

imronco, broken hill australia
September 29, 2015 6:32pm

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