Opponents of legislation to tighten school immunization requirements have been promoting a movie called Trace Amounts to legislators and others. They seem to think this movie proves a link between thimerosal – a mercury-based preservative in vaccines – and autism. It shows, in their view, that our vaccine program is corrupt and harmful through and through, and hence is an argument against vaccine mandates. The movie, however, shows nothing of the sort. There is no new evidence in it, and it simply repeats old and disproven claims.