I would not rule out such a possible causal connection. But.....
Firstly I have already done extensive study concluding that the increase of autism has been entirely due to the introduction of non-gamma-2 dental amalgams 40 years ago. (But this has been blocked from publication by the pseudic "peer review" system.)
Secondly, some "leading experts" are asserting that no increase has happened anyway. As for instance my discussion of this recent paper: https://www.researchgate.net/publication/283543620_Identifying_the_lost_generation_of_adults_with_autism_spectrum_conditions
Article Identifying the lost generation of adults with autism spectr...