Waaaaaay back in the first post of my sub series on vaccines I said I would cover vaccine styles, how they work (and Pt. 2) and why we can’t rely on therapeutics alone. I promise I’ll get to the last one at some point but after a couple of weeks writing about vaccines something occurred to me that I hadn’t really thought about before, what is actually in a vaccine?
In all my undergrad classes I don’t think we ever talked about what else was in a vaccine apart from the intended target of the immune response. This is actually a really important consideration as some people have serious concerns over the safety of the ‘other bits’, which include aluminium, mercury, alcohols and hydrochloric acid.
One of the things I have never understood is why some people seem to assume that researchers and pharmaceutical companies are out to make us sick, they want to make a profit sure but to go all this trouble to inflict harm would be ridiculous. All the legal loops you have to jump through to get a vaccine to market mean that if your goal was to make people sick it would be easier, cheaper and save a lot of time if you just grew some bacterial broths and released them into the water supply. Having said that anti-vaccination activists have a number of ingredients they argue are more damaging than the infectious particles the vaccine is designed to target.
The first big one is mercury. Mercury, aside from being one of the coolest elements (a metal that doesn’t play by the rules, it’s the James Dean of elements), is used to sterilise some vaccine particles. The form that is used is called Thiomersal and is also known as ethyl mercury. Thiomersal has in fact used to sterilise a lot of things and is still used to sterilise liquids like contact lens fluid. Ethyl mercury is bacteriostatic as opposed to bactericidal which mean it simply prevents growth but does not directly kill. Why is it thought to be a problem? It’s the letter ‘M’s fault. Ethyl mercury is fine; METHYL mercury is not so good. The body easily absorbs methyl mercury where it goes to work looking for cysteine residues, which are found in your proteins. Once there it can prevent normal protein function, which, as you would expect, makes normal protein activity, and therefore living, difficult. Intake of METHYL mercury has been linked to developmental defects in children and cardiovascular problems in adults. Importantly, ETHYL mercury has not. Despite this concerns about Thiomersal has resulted in it no longer being used in children’s vaccines, which makes me wonder why it’s still brought up at all?
Another metal anti-vaccination peeps get their knickers knotted about is aluminium and this time they are right. You got me. Aluminium is in vaccines but not without reason. As it turns out, aluminium makes a fantastic adjuvant. Adjuvants are used to increase the efficacy of a vaccine, particularly when the vaccine my not elicit a strong immune response normally. Aluminium hydroxide can be found commonly in the following vaccines Hep A, Hep B, diptheria-tetanus-pertussis, haemophilus, human papilloma virus, and some pneumococcal vaccines. So what does all this Alfoil do in our systems? Nothing, not a single thing. Roughly calculated a 6 month old will receive approx 4 milligrams of aluminium hydroxide (AlOH) in vaccines. In those same 6 months that same baby will have ingested more than 10 milligrams from breast-feeding. If by 6 months that baby is on formula the ingested AlOH could be anywhere between 10 and 50 milligrams! In fact many antacids have AlOH as an active ingredient because it can bind up acids but is also poorly absorbed in the gut such that barely any makes it into the body.
What about hydrochloric acid (HCl)? Surely that’s not put into vaccines. Of course it is. This is one that’s wheeled out because we all know HCl could eat right through steel, or whatever, right? Standard practice in labs all around the world is to use HCl if you need to drop the pH of your solution. In this case vaccines that have a high pH, which could be very dangerous if injected or consumed at this stage are brought back down to a normal range pH (approx pH = 6.8 – 7.2) to make them SAFER!
Despite us knowing that it is very nasty stuff formaldehyde is still used by many vaccine manufacturers. It is used in tiny amounts as a primary sterilising agent that is then almost completely washed off in subsequent sterilisation steps and it’s a natural metabolic by-product of human beings. Yes, in large concentrations it is flammable and can cause significant irritation to your eyes and mucosal membranes if inhaled. It is also a known toxin, allergenic and carcinogen. But it is used in such small amounts and almost entirely removed during the manufacturing process. It is often found in conjunction with Carbolic acid, another notorious ingredient. Together the two chemicals produces phenolic compounds which are used throughout the pharmaceutical industry as sterilising agents. But it has been shown that even aspirin when broken down in the liver results n detectable phenolic compounds.
I could go on and on. The point is that there are plenty of things in vaccines other than the active agent but everything else that is there is used to stabilise, buffer, sterilise or improve the vaccine. Trying to cram in things that will kill you would just take too much extra effort on the part of the evil mad scientists to bother about when we could be off building death rays and electrified shotgun shells. Vaccines are phenomenally safe and heavily regulated to prevent the distribution of poisons, as soon as that changes we will let you know though :) .
Ribeiro CM, & Schijns VE (2010). Immunology of vaccine adjuvants. Methods in molecular biology (Clifton, N.J.), 626, 1-14 PMID: 20099117
BAYLOR, N. (2002). Aluminum salts in vaccines?US perspective*1 Vaccine, 20 DOI: 10.1016/S0264-410X(02)00166-4
Dunning, Brian. “Vaccine Ingredients.” Skeptoid Podcast. Skeptoid Media, Inc., 17 Nov 2009. Web. 5 Oct 2010.
CDC. “Ingredients of Vaccines – Fact Sheet.” CDC. U. S. Federal Government, 19 May 2009. Web. 11 Feb. 2010