What are the limitations of using non-provoked reference ranges to interpret provoked test results?

First of all, there are no standardized reference ranges for provoked tests. Secondly, when a patient utilizes a provocation before testing, their levels may appear (falsely) elevated when interpreted using non-provoked reference ranges. Additionally, the clinical utility of post-provocation urine testing is an area of controversy in environmental medicine. For example, scientific studies demonstrate that administration of chelating agents leads to increased excretion of various metals into the urine, even in healthy individuals without metal-related disease. Ultimately, it is up to the provider to decide whether or not to use a provocation agent before Heavy Metals testing. For more information, please see the Provocation Considerations handout.