My doc had me do a urine and fecal metals test. Both tests showed toxicity in the same metals, and I was almost off the chart on both for mercury and thallium. But the fecal test showed I am literally poisoned by 12 environmental metals you get from eating fish, shellfish and other foods, as well as drinking unfiltered water. I don't drink unfiltered water, but I do eat a lot of fish, and I react poorly to pesticides, which can be full of metals such as arsenic. The doc said he uses both tests because one can give an incomplete picture of someone who is crippled by toxicity.