Study of different normal-microemulsion compositions by room-temperature phosphorescence to determine benzo[a]pyrene in environmental samples

We have studied the presence in the environment of the polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) in the city of Granada using room-temperature phosphorescence (RTP) applied to microemulsions. A detailed study into the different compositions of several normal microemulsion together with experimental variables (heavy atom, deoxygenate agent, pH) and instrumental parameters (wavelengths, decay and gate time) were carried out. The analytical curve has a linear dynamic range of 3.9–100 ng ml−1 with a detection limit of 3.9 ng ml−1. This method does not require any separation step and allows the direct determination of BaP in road dust and in particles deposited on cypress leaves. The application of this approach to road dust and particles on cypress leaves by the standard addition method of calibration gave final concentrations of 17.6 and 14.1 g BaP g−1, respectively. The method is rapid, easy to apply and could be used routinely to determine BaP in environmental samples. © 2002 Elsevier Science B.V. All rights reserved.