Use of headspace solid-phase microextraction coupled to liquid chromatography for the analysis of polycyclic aromatic hydrocarbons in tea infusions

A sensitive and solvent-free procedure for the determination of 11 polycyclic aromatic hydrocarbons in tea infusions using headspace solid-phase microextraction coupled to liquid chromatography with fluorimetric detection is described. A medium polarity polydimethylsiloxane–divinylbenzene 60 μm fiber was found to be suitable for extraction at 90 °C and with an extraction time of 60 min under continuous stirring. Desorption was carried out using the static mode for 5 min. Under the optimized conditions, when 1.75 g of tea sample were extracted with boiling water, the precision ranged from 4 to 16% (RSD) and detection limits were between 4 and 145 ng L−1, depending on the compound. The reliability of the procedure was corroborated by means of GC–MS. The results obtained for a standard reference material were within the range indicated by the supplier.