Journal of Dental Research, Vol 74, 1103-1109, Copyright © 1995 by International & American Associations for Dental Research Online Journals
Combined estimation of mercury species released from amalgam
S. Halbach
Institute of Toxicology, GSF-Research Center for Environment and Health, Oberschleissheim, Germany.
Amalgam fillings constitute, after food, the main source of exposure to
mercury for the general population. Banning amalgam would incur huge costs
for additional dental treatment. An evaluation of potential health risks
must be based on the mercury dose released from fillings. In this study,
dose is estimated by a new procedure of mercury speciation which elutes the
released elemental and inorganic mercury with solvents of differing
polarity. We tested the procedure by incubating spherical amalgam pellets
in a mixture of light paraffin oil and saline (0.9% NaCl). Release of
mercury into paraffin and saline was linear in relation to both amalgam
surface area and exposure time. Measurements with this method were then
extended to a group of 21 amalgam-bearing volunteers. The absorbed dose
averaged 4.8 micrograms/day compared with 3.7 measured conventionally in
intra-oral air from the same persons. With both methods, the dose was
significantly correlated to the number of amalgam-covered tooth surfaces.
This dose, combined with the nearly equal mercury uptake from food, is far
below the acceptable daily intake limit.
