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tissue from fatal poisonings, where dibenzepine was considered to be the only or a contributory cause of death, will be presented. In addition to unchanged dibenzepine, three N-demethylated metabolites were identified in the material by thin-layer chromatography and by UV spectrophoto- metry.

In cases in which death was caused by dibenzepine alone, or in com- bination with alcohol, the concentration of total dibenzepine (dibenzepine + metabolites) was 23 - 14’7 pg/g in the blood and 255 - 566 pg/g in the liver.

Finkle, B. S. (Salt Lake City, Utah, U.S.A.) GC-MS: MARRIED BLISS OR BREACH OF PROMISE?

During the past fifteen years gas chromatography has become the one indispensable tool in most forensic toxicology laboratories. Its power to separate the components of complex biological extracts, with exquisite sensitivity, and practical quantitative accuracy and precision were sufficient justification. A lack of qualitative specificity was the major shortcoming, but alleviation was achieved by extraordinarily innovative techniques such as chemical derivatization and design of selective detectors.

However, some five years ago, after a long engagement with engineers, a remarkable marriage took place; GC to mass spectrometer. The MS endowed the partnership with enhanced sensitivity and quantitation, but above all, specificity and structural analysis. The honeymoon included spectacular success, e.g., in narcotics analysis, and some disappointments, e.g., the inadequacy of interface separator devices; but with offspring such as quadrupole mass filters, multiple ion monitoring, chemical ioniza- tion, interface free instruments using capillary columns, data systems; and a current pregnancy with an atmospheric pressure system, the marriage has apparently matured into a lasting union.

What of operational applications in forensic science? Five years is sufficient to assess if there has been a breach of scientific promise and this paper will introduce a debate that should ensure avoidance of the seven- year itch for new but perhaps less rewarding alternatives.

Finnigan, R. E., J. B. Knight, G. Vander Velde and R. S. Skinner (Sunny- vale, Calif., U.S.A.) APPLICATION OF GC/MS DATA SYSTEM TO FORENSIC TOXICOLOGY

The author will describe the techniques of EI and CI quantitative mass fragmentography and their application to forensic toxicology prob- lems. Three typical applications which will be described are as follows:

Quantitative measurement of propoxyphene and its metabolites in human plasma by EI and CI mass fragmentography using the quadrupole GC/MS system. A comparison of the advantages of EI and CI mass fragmentography will be presented.

The use of solid probe CI-MS and GC-CI-MS in the quantitation of drugs in biological fluids: e.g., the determination of tolbutamide and its metabolites in human plasma will be presented.

Techniques for precise measurement of isotope ratios in biological specimens which contain stable isotope-labelled standards using quantitative mass fragmentography will be described.