Is Metal Toxicity in the Brain a Possible Precursor of Autism?

An old idea that metal toxicity, especially copper and aluminium, that hypothesis I don't think has really panned out. There's not a lot of epidemiology data or human data to sort of really support it, to be honest. But whether there's sort of this causation with these neurodegenerative diseases that are very common, I think is probably not really clear.