I wish that the proverbial "they" were paying me. I'm a history student, and we're not know for our wealth.
I want to make it very clear that chelation therapy is actually harmful. A child was killed as a result of someone using chelation therapy, which bonded to calcium and caused his heart to stop beating. If I need to repeat the most important part of that, I will.
A child was killed. Avoiding vaccination out of a fear that it will lead to autism (although vaccines no longer contain thiomersal) can also cause a child to contract measles or pertussis and expose others to danger. Pertussis, or whooping cough, is a cough so severe that it can cause someone to crack their own ribs. Measles is a preventable childhood illness which can lead to death.
The idea that mercury preservatives in vaccines causes autism has no scientific basis. Numerous studies have been undertaken which have proven that thiomersal (the controversial preservative) does not cause autism. The popularity of the idea comes from the fact that thiomersal was taken out of vaccines as a precautionary move, and from increasing numbers of autism diagnoses. The fact that autism diagnoses are still higher than they were in the past, despite the fact that thiomersal is no longer used but was used as early as the 1930s, should reveal that the increased number of diagnoses comes from other factors, in particular an increased awareness of higher functioning forms of autism which in the past would not have been detected.
Here's a link to a Wikipedia article on the subject:
Thiomersal controversy - Wikipedia, the free encyclopedia
Honestly, though, if you want to believe that thiomersal causes autism, there's nothing that I can do to stop you. Conspiracy theories are notoriously hard to debunk because they are next to impossible to falsify ("they" could always be paying me, or paying people to mislead me), and they shift the entire burden of evidence to the other person, because logically there would be no evidence of a conspiracy. I'm providing evidence, and you can take it or leave it. There's nothing I can do to make you accept that there is no conspiracy.
This is why I don't like conspiracy theories.