Ambient Formaldehyde Levels from Formocresol in a Dental Clinic Environment

Formocresol medicaments used in vital pulpotomy treatment within North America contain 19% or 190,000 parts per million (ppm) (Buckley's) or 48.5% or 485,000 ppm (Sultan's) formaldehyde. Use of these formulations in clinical practice could expose the dental environment to vapors containing formaldehyde. Objectives: The purpose of this study was to measure ambient formaldehyde levels from formocresol within a dental clinic. Methods: Buckley's formocresol (diluted 1:5), Sultan's formocresol and Buckley's formocresol were assessed for formaldehyde vaporation. A Miran 205b Portable Ambient Air Analyzer (Thermo Electron Co., Franklin, MA), a single beam infrared spectrophotometer, was used to determine ambient formaldehyde levels of formocresol formulations under different conditions for 5 minutes: Condition 1) a No. #3 cotton pellet saturated with formocresol with the analyzer 46 cm from the cotton pellet; Condition 2) a No. #3 cotton pellet saturated with formocresol with the analyzer < 3 cm from the cotton pellet; Condition 3) an open bottle of formocresol with the analyzer < 3 cm from the opening. Results: The maximum formaldehyde ppm level (mean ± standard deviation, n = 3) over a 5 minute period was: Condition 1) 0.14 ± 0.02 ppm with Buckley's formocresol (diluted 1:5), 0.29 ± 0.12 ppm with Sultan's formocresol, 0.40 ± 0.26 ppm with Buckley's formocresol; Condition 2) 1.52 ± 0.33 ppm with Buckley's formocresol (diluted 1:5), 6.81 ± 0.68 ppm with Sultan's formocresol, 7.56 ± 1.68 ppm with Buckley's formocresol; Condition 3) 0.42 ± 0.07 ppm with Buckley's formocresol (diluted 1:5), 6.51 ± 2.55 ppm with Sultan's formocresol, 9.40 ± 1.82 ppm with Buckley's formocresol. Conclusions: All ambient formaldehyde levels at 46 cm (approximate exposure distance of dentist or assistant from formocresol source) were below the Short Term Exposure Limit of 2 ppm for 15 minutes (Occupational Safety and Health Administration, USA).