Actually, the responsibility of caution belongs to the medical profession. Autism is increasing and they have shown no care as to what is causing this increase. Parents have to do the best they can with what they know because no one else gives a hoot.
Because you have incidence reportage is NOT an indication of growth. Cancer (of any sort) used to be considered very rare, as science got better at detecting and identifying cancer rates “went up”. Not all cancers will kill you in a short time span. We must be watchful in terms of trying to explain that which may not have an explanation
Last year, the federal government spent $218 million dollars on autism research. Note that the table makes two columns for 2009, 2010, and 2011 spending, to show that "stimulus" funding paid for some of the research.
That is more funding than quite a few other diseases receive. It appears to me that there is a great deal of "care" in determining what causes autism, and how to treat it.