Application of a pentafluorobenzyl bromide derivatization method in gas chromatography/mass spectrometry of trace levels of halogenated phenols in air, water and sediment samples.

An analytical method using pentafluorobenzyl bromide (PFBB) derivatization and gas chromatography/mass spectrometry (GC/MS) has been applied to identify and quantify chloro-, bromo- and dichlorophenols in air, water and sediment samples. Phenols in air sample were collected with a PS-2 Sep-PAK cartridge, and eluted with 2-propanol. For water and sediment samples, liquid-liquid extraction with dichloromethane was carried out, and the solvent was exchanged to 2-propanol. The phenols in the solution reacted with PFBB to form the corresponding pentafluorobenzyl esters. After extracting the derivatives into hexane, the determination was carried out by GC/MS with selected-ion monitoring. The detection limits of phenols in air, water and sediment were 0.0033 - 0.0073 microg/m3, 0.0066 - 0.0147 microg/L and 0.33 - 0.73 microg/kg, respectively. More than 90% recoveries of the halogenated phenols were obtained from real environmental samples spiked by the halogenated phenols. The three isomers of mono-chlorophenols were detected in sediment samples in the range of 5.2 - 9.2 microg/kg in wet weight basis.