DETERMINATION OF COAL-TAR AND CREOSOTE CONSTITUENTS IN THE AQUATIC ENVIRONMENT

Creosote and its parent material, coal tar, are complex mixtures. Upon release their components fractionate into the air, water, soil/sedime nt and biota; as a function of their physical and chemical properties. Therefore, assessment of their fate and concentrations in the environ ment must consider a wide variety of both compounds and matrices. Anal yses are typically complicated, consisting of sample extraction, purif ication and chromatography-based final characterization steps. Several new techniques have been introduced to reduce or simplify the number of steps, solvent and time required. Recently developed extraction met hods include supercritical fluid, accelerated solvent, microwave and s olid-phase microextraction. On-line purification and coupling of extra ction and chromatography have also emerged. HPLC and GC remain the maj or tools for performing the final separations. Application of mass spe ctrometry has increased as more reliable, versatile and less expensive units have become available, such as the ion trap and mass selective detectors. Fluorescence and diode array UV, in concert with HPLC, and C-, S- and N-selective gas chromatographic detectors are also being ap plied.