The wide range of compounds detected (table 1), demonstrates the usefulness of this method for identifying anthroprogenic contaminants over a wide range of sample types. The method also was used on wastewater and river waters samples collected from the Great Lakes region in March, 1998. The river water samples were collected at the surface, near the bank, whereas the wastewater effluents were collected at the outfall. All samples appeared relatively clear of sediment, and none of the samples were filtered prior to extraction. The analytical results for these samples are sumarized in table 2 and figure 2. All 8 sewage treatment plant (STP) samples on the right side of the table show elevated octyl- and nonylphenolethoxylate levels over the river water samples.