Is it safe to inject edta into the blood stream?

Not self inj. The most common side effect is a burning sensation at the site where the edta is delivered into the vein. Rare side effects can include fever, headache, nausea, and vomiting. Even more rare are serious and potentially fatal side effects that can include heart failure, a sudden drop in blood pressure, abnormally low calcium levels in the blood, permanent kidney damage, and bone marrow depression.
Chelation Therapy. Yes, it has been used in chelation therapy to prevent blood clots from clogging up arteries of vital organs. Recent studies show no significant benefits compared to other means of thinning your blood.