AN OVERVIEW ON THE STANDARDIZATION OF CHROMATOGRAPHIC METHODS FOR SCREENING ANALYSIS IN TOXICOLOGY BY MEANS OF RETENTION INDEXES AND SECONDARY STANDARDS .1. GAS-CHROMATOGRAPHY

In systematic toxicological analysis, in which a logical analytical se arch for a potentially harmful substance has to be carried out, chroma tographic methods are of utmost importance since the retention paramet er can be used for primary identification. In gas chromatography the K ovats retention index (RI) system is generally accepted for standardiz ation of the retention. In order to increase the reproducibility of th e interlaboratory RI, secondary standards for RI calculation have prov en to be very useful. The best secondary standards are those that are structurally resembling the substances under investigation. For exampl e, for general toxicological screening analysis, mixtures of drugs are recommended. Stationary phases consisting of Carbowax are most extens ively used for solvents and volatile compounds; for less volatile comp ounds SE-30/OV-1/dimethylsilicone stationary phases have proven to be useful. For these types of stationary phases extensive data compilatio ns comprising over 6000 substances are available for use in toxicology .