Dr Christopher Exley of Keele University in the UK found some of the highest levels of aluminium ever recorded in the brains of five people who were autistic when they were alive.
The levels were similar in all the brains tested, even in the brain of a 15-year-old, which would rule out environmental factors being solely responsible. Levels in the brain sample were at least 10 times higher than should be seen in someone of his age. "Perhaps we now have the putative link between vaccination and ASD (autism spectrum disorder), the link being the inclusion of an aluminium adjuvant (an immune-response activator) in the vaccine," Dr Exley wrote in an accompanying blog.
Most of the aluminium was found inside non-neuronal cells, which suggests that inflammatory cells—already loaded with aluminium—were entering the brain from an outside source and were passing the blood-brain barrier. The pattern is unique to ASD sufferers, he says.
There were several theories as to why ASD sufferers have such large amounts of the metal in their brains. They could have a genetic predisposition, which makes them more liable to accumulate and retain aluminium, or it could be the adjuvants in vaccines—or even a combination of the two.