Chelation therapy is quackery, pure and simple, as far as I can tell.
Well, maybe you should look further.
Chelation is a well established medical solution to Heavy metal poisoning, and has been for over 40 years.
IV chelation for lead poisoning is well established; its been used for over 50 years. The theory that mercury is responsible for autism needs more proof. During IV chelation it is crucial to monitor electrolytes. The EDTA combines with calcium, potassium, etc. and an imbalance can lead to cardiac arrest. Oral chelation is cheaper and safer. I have been using small doses of oral EDTA for several years to remove heavy metals from my body. Since good metals, e.g., selenium, are also removed, I take a broad mineral supplement, Vitamin Research Products Advanced Essential Minerals.