Flow methods for the determination of polycyclic aromatic hydrocarbons using low power photomultiplier tube and charge coupled device chemiluminescence detection

Polycyclic aromatic hydrocarbons (PAHs) are produced during combustion processes (both natural and anthropogenic), and as a consequence are distributed widely throughout environmental systems. This paper describes the application of peroxyoxalate chemiluminescence (CL) detection, with a 12V low power photomultiplier tube (PMT) detector and a two-dimensional charge coupled device (CCD) detector, to the determination of PAHs. The PMT system provides comparable sensitivity to high power (1 kV) PMTs (detection limits in the pg range) and complementary information to that derived from fluorescence detection. The CCD system can be used to obtain full CL spectral information (in contrast to the integrated response from PMTs) and it has been shown that multivariate calibration can be used in conjunction with CCD detection to give good predictive errors (<9%) for simple two-component systems, e.g. benzo[k]fluoranthene and benzo[a]pyrene in hexane.