Who is keeping track of the mercury content issue? If the autism cause is right, as vaccines used less or no mercury, which would be an undesirable element for other reasons, the problem ought to have diminished or disappeared. Also it would be interesting to see how it was tied to other sources of trace mercury such as wild caught seafood.
Nothing to track. The anti vaccine stuff originated w/an Andrew Wakefield study. All of his stuff and similar were completely debunked.