Could you tell me about the positive and negative of chelation therapy for arteriosclerosis?

Gray area: Many studies have shown no benefit over the years but the most recent study, published in the last year did show some benefit. It's a gray area right now, certainly far from proved, and not mainstream. I'd stay away from it. In the 1970s there were many shadowy clinics offering it and the only ones who definitely benefitted were the ones who got paid for it.