The Mercury Tri-Test
Why Our Mercury Tri-Test is Better Than Challenge Testing
- The Challenge Test does not differentiate between MeHg and Hgll. Only Total mercury level is represented (HgT).
- The Challenge Test does not reflect the “pool” of mercury premise.
- There is no “non-challenged” reference range to compare the Challenge Test; from a regulatory standpoint, there is an obvious potential for over-treatment.
– DMPS has a very different strength and specificity than DMSA.
– IV vs. oral administration has vastly different pharmacokinetics.
– Use of adjuncts such as EDTA, glutathione, and glycine notably changes the dynamics of the test and its output. - Lack of standardization of challenge conditions.
– Challenge does not reflect long-term exposure as proven by clinical trial* reference p.120.
– Challenge does not reflect long-term exposure as proven by clinical trial* reference. - Challenge exposes individual to a large dose of exogenous substance.
- Challenge may cause redistribution of mercury into organs, including the brain.
- Challenge does not measure ambient mercury burden.
- Challenge does not elucidate elimination abilities of the patient.
- Challenge results can be skewed in individuals with renal insufficiency (common in Hgll toxicity).
What About Mercury Challenge Testing?
Quicksilver Scientific’s Mercury Speciation Testing
The Mercury Challenge Test
The Truth About Testing:
Challenge Testing Vs. Mercury Speciation Testing
For over two decades now, many clinicians have been relying on “challenge tests,” also called provocation tests, to diagnose mercury and other metal toxicities. The diagnostic premise of the testing is that it shows the “body burden” of the individual–that pool of deeply held metals that represents our lifetime accumulation of un-excreted metals. The literature examining the challenge tests ranges from the years 1991 through 2001 and has thus far failed to find any evidence of the challenge tests revealing any more than recent exposures, and in some instances (Frumkin et al, 2001) failing to see exposures made clear by ambient testing. Recently, challenge tests have come under fire from federal authorities as a diagnostic tool. The problem is not really that the challenge tests have no use (especially in the case of lead, where EDTA challenge testing is documented to have slightly better correlations with bone lead than do blood lead measurements or the case of gadolinium where levels in blood and urine are undetectable without EDTA provocation). Instead, the problem is the way they are generally used and interpreted. There are many practitioners who use the data from challenge tests in scientifically and clinically valid ways, but in general use, the challenge test has three main flaws:
- The propagation of the myth of a special relevance of the pool identified by the challenge, i.e., “body burden,” and the yes/no interpretation, i.e., “I found mercury in the patient.”
- The use of a non-challenged reference range to compare the challenge test; this is probably the biggest problem from a regulatory standpoint since there is such obvious potential for over-treatment.
- The lack of standardization of the challenge conditions:
– DMPS has a very different strength and specificity than DMSA.
– IV vs. oral administration has vastly different pharmacokinetics.
– Use of adjuncts such as EDTA, glutathione, and glycine vastly changes the dynamics of the test and its output.
The measurement of mercury in the body and extrapolation to body burden and toxic conditions is a very complicated field, requiring acute clinical discernment, including integration of patient history, current exposures, symptomology, and effect of co-morbidities. The simplification and deification of the challenge test are no longer serving the evolution of the field of clinical metals toxicology. Now is the time for adoption of better tools!
At Quicksilver Scientific, we have developed advanced mercury test kits that:
- Identify different sources of mercury by measuring the relative amounts of the two main forms of mercury in the body—methylmercury and inorganic mercury.
- Quantify excretion capabilities for those two forms.