The active constituents in allergenic extracts of Poison Ivy and other plants of the genus toxicodendron have been generically designated as """"""""urushiol"""""""", a mixture of penta-or heptadecenyl catechols. Objectives of this project are: a) to develop methods for the quantitative analysis of urushiol, including speciation of individual compounds; b) to develop sample preparation techniques to isolate urushiol from plant oil matrices; c) to develop methodologies to determine oxidized and oligomerized urushiol degradation products; d) to correlate urushiol degradation with factors of concentration, solution type and storage conditions. Urushiol samples have been speciated and quantitated by gas chromatography of trimethylsilyl derivatives. Validation studies have been performed for this method. A normal phase HPLC method utilizing a silica column is to be investigated. Development of a capillary gas chromatographic procedure, providing better resolution of individual compounds is in progress. Procedures for the isolation of urushiol at high (greater than 100 ppm) concentrations from plant oils have been validated.