A new method for the measurement of airborne formaldehyde using derivatization with 3,5-bis(trifluoromethyl)phenylhydrazine

grantor: University of TorontoA new method is described and validated for the measurement of airborne formaldehyde using solid phase extraction (SPE) cartridges impregnated with 3,5-bis(trifluoromethyl)phenylhydrazine (TFMPH). Analysis by gas chromatography with electron capture detection (GC-ECD) provides a detection limit of 74 ng formaldehyde per sample. A field study was conducted to compare the use of this method to the US Environmental Protection Agency (EPA) method TO-11, which uses 2,4-dinitrophenylhydrazine (DNPH) and the National Institute for Occupational Safety & Health (NIOSH) chromotropic acid (CTA) method (NIOSH method 3500). Samples were collected from a variety of indoor and outdoor environments known or suspected to contain formaldehyde, Use of TFMPH with GC-ECD analysis correlates well with both methods (R2 = 0.93, slope = 1.09 vs. DNPH; R2 = 0.96, slope = 1.01 vs. CTA). Spiked samples were shown to be stable at least 14 days when stored at -20°C. Analysis of samples by gas chromatography-mass spectrometry with selected ion monitoring (GC-MS/SIM) has also proved feasible, with a detection limit comparable to that obtained by GC-ECD. All instrument calibrations were carried out by vapour spiking precise masses of aldehyde onto the sampling cartridges. For field sampling at environmental concentrations (