Journal of Dental Research, Vol 71, 66-74, Copyright © 1992 by International & American Associations for Dental Research Online Journals
Factors affecting blood mercury concentrations in practicing dentists
S. B. Chang, C. Siew and S. E. Gruninger
Department of Toxicology, American Dental Association, Chicago, Illinois 60611.
It has been suggested that mercury vapor may be transformed into highly
toxic organomercury compounds by micro-organisms in the oral cavity and
gastrointestinal tract. If this hypothesis is correct, practicing dentists
might be expected to have concentrations of organic mercury in their blood
higher than that found in non-dentists. Blood mercury concentrations of
practicing dentists and non-dentists were determined by means of cold-vapor
atomic absorption spectrophotometry. Potential sources of mercury exposure
were identified in both dentists and non-dentists through a questionnaire
completed at the time of sampling. Concentrations of total and inorganic
blood mercury were significantly higher in dentists than in non-dentists.
The organomercury concentrations of the two groups were not statistically
different (p greater than or equal to 0.05). The high concentration of
inorganic mercury in the blood of dentists was not related to the
organomercury level, suggesting that biotransformation of inorganic mercury
to organomercury does not occur in vivo. However, the concentration of
blood organomercury was positively correlated with the frequency of fish
consumption. There was no correlation between the number of amalgam
restorations and the concentration of inorganic blood mercury for both
groups. Accidental mercury spills in the dental operatory may contribute
most to the concentration of inorganic blood mercury in the blood of
dentists.
