Mercury in dental clinic: weekly concentrations in the workplace and its relations with dental procedures in São Gonçalo, Rio de Janeiro State, Brazil

Abstract

The aim of this study was to evaluate occupational exposure to mercury in a dental office, measuring mercury concentrations by using a portable mercury analyzer (Lumex). Measurements were taken every hour during the working week in an office, located in São Gonçalo, Rio de Janeiro State, Brazil. Mercury concentrations in ambient air were evaluated after performing 175 procedures. The procedures were divided in three groups according to the use of mercury and the dental high-speed handpiece. The average mercury concentration observed in the clinic's air was 2.49 µgHg.m^-3, reaching 4.69 µgHg.m^-3 on the day on which the greatest number of procedures was conducted. The procedure of placing amalgam led to the highest average of mercury concentration in the air, but it was not statistically significant in relation to other groups of procedures (p-value = 0.988). The data collected in the environment have shown that mercury concentrations were within the limits established by Brazilian and international law.