Real-time measurements of formaldehyde emissions in a gross anatomy laboratory

Abstract

Formaldehyde is recognized to be a carcinogen and a genotoxic indoor pollutant. The National Institute for Occupational Safety and Health (NIOSH) identify 1 ppm as the ceiling limit, a value which should not be exceeded at any time. This low ceiling limit generates the need for real-time monitoring; which can, however, lack in accuracy. In this project, formaldehyde low-cost monitors are both evaluated in a laboratory platform and in an indoor environment. Using a controlled environmental chamber, the formaldehyde sensors show a linear regression coefficient R2 of 0.98 when compared to the reference method [NIOSH 2016, based on 2,4-dinitrophenylhydrazine (DNPH) derivatization]. Readings taken with the calibrated low-cost monitors in a gross anatomy laboratory, where embalmers, medical students and staff are exposed to formaldehyde and other toxic volatile organic compounds, show that the embalming and dissection processes generate average values of about 900 and 1300 ppb, respectively, when corrected for phenol interference. The corrected average values are within 20% of the reference method values. Real-time data for the same processes show maximum concentrations (1-min average) of about 3.5 ppm in both embalming procedure and dissection laboratory. Therefore, real-time monitoring can show values of formaldehyde exceeding the acceptable exposure short-term limit and ceiling limit.