Laser-induced fluorescence of pyrene and other polycyclic aromatic hydrocarbons (PAH) in seawater.

Polycyclic aromatic hydrocarbons (PAH) in the marine environment are currently of great concern due to their potential carcinogenicity. The standard methods of detection and quantification of PAH in seawater and sediments are costly, time-consuming and do not account for the heterogeneous nature of their distribution and sources. Laser-induced, time-resolved fluorescence spectroscopy may help to overcome these limitations. Several PAH have relatively long-lived stimulated fluorescence emissions, which allow them to be detected among a background of more intense but shorter-lived chromophores. Using time-delayed techniques we have shown an ability to detect PAH, principally pyrene, at environmental levels (ng l(-1)) both in the laboratory and in situ in Boston Harbor and other study areas. Further development may lead to the rapid determination of several PAH in typical near-shore marine environments.