I meant, I completely agree with Tena Cious above, saying that blood/urine tests are misleading or useless.
Regarding the use of a chelator to provoke the release of heavy metals from tissue: DO NOT DO THIS, you will regret it later. Challenge tests are like taking poison. It will re-poison you all over again. Why don't you fire your doctor, buy the Cutler book, and chelate on your own? You will save yourself a lot of pain and wasted time.
You see, a medic has a license to uphold, so they will make you jump through hoops and loops so that they can cover their butt, to hell with your well-being. I am generalizing somewhat, but this is what the system makes them do: follow the script, test you to oblivion, prescribe stuff and not shake the boat as not to disturb the establishment above them in the pecking order of modern medicine.