Heavy Metal Testing
Exposure to heavy metals can occur inadvertently – car exhaust, lead-based pain, flame retardant on children’s clothing, dental fillings, and can have myriad negative health effects. Heavy metals include mercury, lead, arsenic, and cadmium.
Long-term exposure to small amounts may not cause immediate acute symptoms and cannot be tested for in the blood, but nonetheless can cause health problems. These can include neurological, hormonal, and immunological issues.
Naturopathic doctors frequently employ urine provocative heavy metal testing in patients suspected of heavy metal exposure. The test is relatively simple involving collection of a series of urine samples before and after administration of a chelating agent. This is referred to pre-challenge and post-challenge urine collection.
Different chelating agents are used for specific heavy metals. Examples include EDTA and DMSA. The pre-challenge urine samples provide an estimate of chronic metal exposure – it estimates how much is currently circulating in the body and being excreted by the kidneys. These measurements are generally low unless there has been recent exposure to heavy metals. The post-challenge collection shows higher levels of heavy metals in cases of heavy metal toxicity. The chelating agent provokes release of heavy metals stored in tissues into circulation to be excreted by the kidneys. Post-challenge levels will show past or chronic heavy metal exposure.
Urine is collected for 6 hours post administration. For patients deemed to have excess heavy metals and are experiencing symptoms, chelation therapy may be used. This often involves IV administration of a chelation agent such as EDTA (ethylenediaminetetraacetic acid), or and oral protocol using DMSA.
It is very important that the liver and kidneys are functioning properly before administering the chelating agent. Many naturopathic physicians will prescribe liver support formulas to patients who undergo this test and who are undergoing heavy metal detoxification regimens. It is important to remember that a chelation agent will also remove minerals, including calcium and zinc, and therefore be replenished post-treatment.
For additional information, check out the following articles. If you are concerned about heavy metal toxicity or have additional questions about heavy metal testing and chelation therapy, consult a naturopathic doctor.
http://www.drmarchese.com/images/provocative_heavy_metal_testing.pdf
