Complex sentence: He is one of the most public faces of the scientific consensus that vaccines have no association with autism, and has, as a result, attracted controversy and a substantial volume of hate mail and occasional death threats, but also support for his position.
Split into simpler sentences: He is one of the most public faces of the scientific consensus that vaccines have no association with autism. As a result, he has attracted controversy, and both a substantial volume of hate mail and occasional death threats, as well as support for his position.