Statistical Factors Associated with Mercury and Selenium Concentrations in Blood of Dental Staffs

Relation to Amalgam-Handling

Abstract

Mercury and selenium concentrations in whole blood of 125 dental staffs (32 dentists,43dental hygienists,15 dental technicians,15 dental assistants,11 clerical workers and 9 members of dentists' families) were determined and their amalgam work, own amalgam fillings, dietary habit, smoking and alchol consumption were also investigated by a questionnaire. Association of these factors with blood mercury and selenium was studied.
1. Among 32 dentists,2 dentists routinely handled amalga m as a filling material.
2. Mercury and selenium concentrations in whole blood of 125 denta l staffs (mean with range in the parentheses) were 20 (5-82) ng/ml and 144 (63-365) ng/ml, respectively. These values are within normal ranges of the elements in blood of gene r al Japanese adults.
3. A significant correlation (r = 0.52, p<0.01) between the mercury and selenium concentrations was observed in male dental staffs.
4. There was no difference between dental staffs with amalgam work and those without amalgam work in the mercury concentrations.
5. Multiple regression analysis showed that the habitual fish intake was a significant factor contributing to the selenium concentrations and that the habitual fish intake and own amalgam fillings were probable factors contributing to the mercury concentrations.
These results lead to a conclusion that the amalgam work did not effect on the mercury and selenium concentrations in whole blood of the dental staffs and dietary habit is more important factor contributing to the both elements in blood than the amalgam work.