Exposure of staff to aerosols and bioaerosols in a dental office

Abstract

Aerosol and bioaerosol concentration measurements were performed in a dental office during routine procedures. Average mass concentrations of submicrometer PM1 particles and supermicrometer PM>1 particles during dental procedures were respectively 3.8 and 6.5 times higher than in the period when no procedures were conducted. They were also respectively 15.9 and 19.5 times higher than their average outdoor levels. For average number concentrations of submicrometer PN1 particles and supermicrometer PN>1 particles, the elevation rates amounted to respectively 1.8 and 4.2 and the concentrations were respectively 2.8 and 53.4 times higher than average outdoor levels. During the procedures, bacteria and fungi concentrations increased about 2.1 and 1.7 times, respectively. The dentist's exposure to contaminants and the inhaled doses were significantly higher while performing dental procedures than in the period when no procedures were carried out. The contamination factor values defined as the ratios of outdoor-corrected indoor to outdoor-corrected background concentrations for PM1 and PN1 particles were on average respectively 3.9 and 2.2 times higher, and for PM>1 and PN>1 on average 6.7 and 4.1 times higher. The contamination factor values for bacteria and fungi were respectively 4.1 and 3.6 times higher. The greatest number of the released particles was in the nanometer region showing peaks in the range between 0.052 and 0.072 μm. In terms of mass, particles with sizes of about 1 μm had the lowest contribution. Such particle size distribution may facilitate the infection risk of airborne transmission diseases, including ones caused by SARS-CoV-2.