The use of chloroform as an adjunct to the practice of endodontics has been a matter of debate. In the present study the chloroform uptake of gutta-percha cones was determined by a gravimetric assay for different times of chloroform dip. In conjunction with an assessment of the amount of gutta-percha dissolved during dip, this provided an estimate of the amount of chloroform that patients are exposed to in clinical conditions. An assay was also performed of the chloroform concentration in the air in a dental office. Chloroform uptake was shown to increase with an increasing dipping time. There also seems to be a difference in this uptake between pure chloroform and a chloroform preparation with colophonium. The concentration levels of chloroform evaporated during the practice of chloroform dip within a dental office do not exceed the safety limits.