This collection includes infrared spectra of the chemicals listed by the EPA as Priority Pollutants, as well as other major industrial chemicals. Compounds which are closely related structurally to priority pollutants, or are likely to be contaminants arising from the same chemical process, are also included to help the spectroscopist with important analyses. Over 600 spectra are provided. They include multiple physical states, especially for compounds whose spectra are sensitive to the sampling environment. A special group of spectra of mixtures likely to be involved in spills or seepage such as gasolines, fuel oils, and common solvent blends will be of great value to analytical laboratories in environmental and forensic fields alike. Evaluation has been carried out with careful band-by-band comparison with other spectra, which is typical of the Coblentz Society's evaluated spectral data program.