Microprobe Laser Mass Spectrometry Studies of Polycyclic Aromatic Hydrocarbon Distributions on Harbor Sediments and Coals

Abstract. Microprobe two-step laser mass spectrometry (μL 2 MS) was used to assess the distribution and origin of polycyclic aromatic hydrocarbons (PAHs) on sediment particles dredged from the harbor of Milwaukee, Wisconsin. PAH concentrations are largely associated with coal-derived particles and other carbonaceous environments. PAH distributions on these coal-derived particles and carbonaceous environments, which are thought to have separate origins, were found to be quite similar. μL 2 MS data of coal and thermally-processed coal showed profound differences from μL 2 MS data obtained from the coal-derived particles in the sediment. The results of these experiments indicate that the coal-derived particles are not the source of PAHs in the sediment but are scavengers of PAH contaminants in the Milwaukee Harbor sediments