Abstract Mustard green samples were analyzed by the official method for nicotine content. The final determinative step was made on a gas chromatograph equipped with a thermionic detector (coated with KC1). The final extract was chromatographed on a 6' X 4 mm i.d. glass column containing Gas Chrom Q coated with 10% DC-200 and maintained at 125°C. Flow rate (nitrogen) was 135 ml/niin. Amounts as low as 0.3 μg nicotine were detected. Response was linear from 0.1 to 1.0 μg. For identification, a portion of the effluent was split and 2 or 3 combined injections were trapped in petroleum ether and spotted on a TLC plate as described in This Journal, 49, 175— 179 (1966).