Mercury Level Analysis
While blood levels are useful for more acute exposures, long-term exposures are best reflected in hair mercury measurements. Hair has high sulfhydryl content. Mercury forms covalent bonds with sulfur and, therefore, can be found in abundance in hair samples.
Urine mercury level can be tested before and after intravenous DMPS challenge. When there is sharp increase of mercury it is suggestive for high mercury level in the tissue.
Toenail mercury has also been used as a measure of long-term mercury exposure.
Mercury accumulate in red blood cell for about 44 days, therefore generally blood is tested for acute toxicity.
Because mercury binds to the body’s ubiquitous cellular sulfhydryl groups, chelating agents is the treatment of choice. Chelating agents contain thiol groups, which bind to mercury. Chelation with 2,3-dimercaptosuccinic acid (DMSA or succimer) has been shown to result in increased mercury excretion. DMSA is generally well tolerated and has also demonstrated efficacy in children exposed to mercury. Chelation treatment may be administered in the outpatient setting with an oral chelator, such as DMSA.
For acute, inorganic toxicity, dimercaprol (British antilewisite [BAL]) has traditionally been recommended, but oral agents are gaining prominence.