[A] debate continues as to whether neonate and infant exposure to aluminium through vaccination is biologically significant with respect to their exposure to aluminium through other routes and especially diet…
[P]aediatricians… seem in particular, to be uninformed about the properties of aluminium adjuvants and their mode of action in vaccines.
An appreciation of how much aluminium is present in a single injection of a vaccine is critical to understanding how aluminium adjuvants are effective in stimulating the immune response.
Currently about 20 childhood vaccines include an aluminium adjuvant.
The aluminium salt is the major component of a vaccine (after water) and its high content is why vaccine preparations are invariably cloudy in appearance.
An aluminium-adjuvanted vaccine is essentially a very high concentration of an aluminium salt… in which just μg [mcg or micrograms] of other vaccine components including antigens and other excipients are occluded.
All… of the aluminium salt… will immediately be systemic [once injected]; it is inside the infant’s body.
[I]njected aluminium may only leave the body through its excretion in either the infant’s urine or sweat.
[C]hemical and biological processes will initiate the slow redistribution of the injected aluminium throughout the infant’s body.
[A]luminium injected into muscle as an adjuvant in a vaccine potentially has uninterrupted access to the infant brain.
[I]t can be estimated that 10% of ingested aluminium or 0.01 mg/day of aluminium in breast milk is absorbed across the infant gastrointestinal tract. However, the blood carrying nutrients and toxins that have been absorbed from the gut, to the rest of the body must first pass through the liver, the major detoxification system of the body.
When these various conditional factors are accounted for it can be estimated that an infant’s exposure to systemically available aluminium from breast-feeding is approximately 0.005 mg of aluminium each day.
On day 56 the infant receives a single dose of 0.82 mg [820 mcg] of aluminium in the Infanrix Hexa vaccine [licensed in the UK], a dose equivalent to 3 times the amount of aluminium the infant received during the entire 55 days of life prior to its vaccination.
[I]n a worst-case scenario an infant only being formula-fed from birth might be exposed to 0.030 mg of aluminium each day up to vaccination on day 56. Even in this worst-case scenario, the exposure to systemically available aluminium on vaccination day is 25 times higher through the vaccine than through the diet.
Aluminium adjuvants are not inert depots at the vaccine injection site; they are sources of biologically reactive aluminium.
The concentration of systemically available aluminium immediately present at the injection site of a vaccine is very high in comparison to studies on cell cytotoxicity in the scientific literature. It is an acute exposure to aluminium and it results in significant cytotoxicity including necrotic cell death. The resulting tissue inflammation is the characteristic red mark on the skin at the injection point. This acute toxicity in the immediate vicinity of the injection site underlies the success of aluminium salts as adjuvants in vaccinations.
[A]luminium-loaded cells remain viable for days, potentially weeks, which means that they can transport their cargo of aluminium anywhere in the body including the infant brain. The recruitment of systemic cells including macrophages to the central nervous system is a widely documented phenomenon.
There is now a viable mechanism for the accelerated loading of an infant’s brain with aluminium and evidence to support such a mechanism was demonstrated in our recent paper on aluminium in brain tissue in autism.
A single dose of [a] vaccine [containing 820 mcg alum] is equivalent to the exposure to aluminium that an infant would receive from 150 days breast-feeding.
[A]n infant would receive a further two doses of this vaccine during the aforementioned 150 day period.
In the United Kingdom [and the US] it is not uncommon for an infant to receive… three… aluminium adjuvanted vaccines on the same day.
The latter, acute versus chronic exposure, while not yet being taken into account in infant vaccination programmes, must now be considered to help to ensure that future vaccination schedules are safe. Currently the EMA and the FDA limit the aluminium content of a vaccine to 1.25 mg.
This limit is based upon the aluminium adjuvant’s efficacy in inducing antibody titres. Perhaps now is the time to revise this limit based upon additional factors of vaccine safety.