Is there a hazard to health by mercury exposure from amalgam due to MRI?

The local magnetic fields from computer monitors are well known. Recently a hypothesis was published that these magnetic fields may lead to a 400% increase of mercury dissolution from dental amalgam fillings. In MRI the exposure to the magnetic field exceeds by far the exposure from computer monitors. Therefore, this study examined the amalgam-related mercury release for typical MRI conditions, separated for both the static and the variable magnetic fields in a 1.5 T MR-unit. First, 20 dental cavities were filled with a non-gamma-2 amalgam, and the mercury release was measured for 14 days in a non-magnetic environment. Second, one half of the specimens were exposed to a static magnetic field for 24 hours (group A), while the other specimens were exposed to a repetitive gradient echo sequence for 60 minutes (group B). In both experiments there was no significant increase in mercury release due to MRI. This in vitro study demonstrated no evidence of an elevated mercury dissolution from a non-gamma-2 amalgam during magnetic field exposure by MRI; therefore, there is no increased risk to health.