Factors affecting blood mercury concentrations in practicing dentists

Area of Science:

• Environmental Health
• Occupational Health
• Toxicology

Background:

• Concerns exist regarding microbial transformation of mercury vapor into toxic organomercury compounds in vivo.
• This biotransformation could lead to elevated organic mercury levels in individuals with high mercury exposure, such as dentists.

Purpose of the Study:

• To investigate whether practicing dentists exhibit higher blood organomercury concentrations than non-dentists.
• To explore potential sources of mercury exposure and biotransformation pathways in dentists.

Main Methods:

• Blood samples from dentists and non-dentists were analyzed for total, inorganic, and organic mercury using cold-vapor atomic absorption spectrophotometry.
• Questionnaires identified potential mercury exposure sources, including dental work and fish consumption.

Main Results:

• Dentists showed significantly higher concentrations of total and inorganic blood mercury compared to non-dentists.
• No statistically significant difference was found in blood organomercury concentrations between dentists and non-dentists.
• Blood organomercury levels were positively correlated with fish consumption frequency.
• Inorganic mercury levels in dentists were not linked to organomercury levels, suggesting limited in vivo biotransformation.
• No correlation was observed between amalgam restoration numbers and inorganic blood mercury levels.

Conclusions:

• The study did not support the hypothesis of significant in vivo biotransformation of inorganic mercury to organomercury in dentists.
• Elevated inorganic mercury in dentists likely stems from occupational exposure, such as accidental mercury spills.
• Dietary factors, particularly fish consumption, are a significant determinant of blood organomercury levels.