On 3 September 2017, a Facebook page promoting the anti-vaccine movie "Vaxxed" shared a video of an undeniably cool science experiment (which they appear to have since removed). This video, which featured a chemical reaction between aluminum and mercury resulting in the creation of a grotesque, gothic looking tower of aluminum oxide, is irrelevant to vaccine safety in myriad significant ways. Despite this irrelevance — and without actually offering a concrete scientific principle of which to be afraid — the video was captioned:
Hmmm... What mandated medical injections also combine thimerosal (mercury), which still remains in several vaccines and aluminium, used in almost all vaccines? It's time to reject vaccine MYTH and embrace the truth.
The answer to the post's unnecessarily rhetorical question, which attempts to exploit fears over the mercury based preservative thimerosal and a series of aluminum-containing ingredients in some vaccines, would have been fairly easy to look up prior to posting and then deleting: none. Of all the vaccines approved for use in the United States, only one — a tetanus and diphtheria vaccine — contains both the mercury-derived thimerosal and an aluminum compound (aluminum phosphate). This vaccine, however, is not mandated.
It is also irrelevant, because a reaction between thimerosal and aluminum phosphate is fundamentally different than the one in the video. In the original version, posted by YouTube chemical reaction filmer NileRed on 13 August 2017, the two reactants were metallic mercury (Hg) and metallic aluminum (Al).
In contrast, the theoretical reactants hypothesized by the post would be thimerosal, a mercury-containing organic compound (C9H9HgNaO2S), and aluminum phosphate (AlPO4), a mineral. These two chemicals share little with the elemental metals used in the video, because they are literally different chemicals. Just because two compounds might share the same element does not de facto mean they will behave in similar fashion. Metallic elemental sodium creates a wildly dangerous explosion if it comes into contact with any moisture. Sodium when chemically bonded with chloride, however, becomes table salt.
Finally, the edited version of the video neglected to show how challenging it was to get the reaction started in the first place, as well as to mention the rather significant fact that it included a third chemical to initiate the reaction. Because metallic aluminum, when exposed to oxygen, is naturally coated in aluminum oxide, the mercury needs to be in contact with freshly exposed aluminum metal. The YouTube scientist first tried scraping at the aluminum while the liquid mercury rested on top, then turned things up a notch with the use of a drill. No luck. He finally solved the problem chemically by reacting the aluminum surface with hydrochloric acid, as narrated in the original video:
Under normal conditions, aluminum is surrounded by a protective oxide layer. Metallic mercury isn't able to penetrate through this barrier, so it kind of does nothing. Sometimes it's possible to get things going by manually scratching away the oxide layer. I tried doing this about two or three times, but it wasn't working for me. I even tried to bruteforce things using a drill, but that didn't get things going either. [...] I took out all the mercury and I added some dilute hydrochloric acid. The hydrochloric acid quickly reacts with the oxide layer and dissolves it away. This exposes fresh aluminum metal.
Needless to say, these are not the conditions (or even the chemicals) one would find in a vaccine of any kind or within the human body. NileRed described the process behind the footage in his video, as well:
The major thing going on here is the combination of the mercury with the aluminum to form the amalgam [a chemical term for an aluminum based alloy]. Some of the amalgam that forms gets dissolved in the mercury and makes its way to the top. When it gets there, it comes in contact with oxygen in the air, and it reacts to form white aluminum oxide. This part of the process is pretty short-lived, though, because it quickly gets covered and protected by the oxide. This prevents fibers from growing directly from the mercury, but obviously they continue going out from the sides. [...] The dissolved mercury can continue to creep along the surface and amalgamate more aluminum. In theory, this process should keep going until the entire surface is covered with a thick layer of the oxide.
A fascinating series of events, to be sure, but ones that are ill-suited for commentary on vaccine safety.