ABSTRACT
Some recent studies of methods for identifying weathered oils through chemical fingerprints (passive tagging) are reported. These studies were performed by Esso Research and Engineering Company, Phillips Scientific Corporation, Woods Hole Oceanographic Institution, and Baird Atomic Corporation under U.S. Environmental Protection Agency (EPA) sponsored grants and contracts. A broad range of analytical instruments and techniques were used, e.g., adsorption chromatography, molecular emission and absorption spectrophotometry, atomic absorption spectrophotometry, gas chromatography, computerized mass spectrometry, et. al. Some of the oil parameters evaluated as potential fingerprint indices are vanadium, nickel, sulfur and nitrogen content, gas chromatographic profile appearance, carbon and sulfur isotope ratios, API gravity, and pour point. Several promising methods for passive tagging oils are suggested by these studies.