I believe that everything, including vaccinations, have contributed to the rise in autism/Asperger's. In my State, New Jersey, studies have shown that 11 out of every thousand children have been diagnosed mild to severe autism - the highest in the nation. Everything that we eat, breathe, sit on, wear, and are in proximity of is outgassing toxins at a rate that has never before been experienced by humankind, as a species. With the exception of natural catastrophes, the time required for any species to develop immunities to specific environmental variables is measured in millenia, not decades. In the past 100 years, we have gone from combustion engine to string theory. With history as evidence, something will stop this runaway train, whether it's natural or manmade, I guess.