Nitrous oxide concentrations in the dental surgery, Atmospheric and blood concentrations of personnel.

Pollution in the dental outpatients surgery was assessed by measuring atmospheric nitrous oxide levels and comparing these with the venous blood concentrations in the operator-anaesthetist and his assistant. The effects of scavenging on both measurements have also been determined. Without scavenging the nitrous oxide level in the blood of the dentist was over four times that of the average anaesthetist working in an operating theatre. Some of the factors contributing to these high levels, and the effectiveness of scavenging are discussed.