Rendering the "poppy-seed defense" defenseless: identification of 6-monoacetylmorphine in urine by gas chromatography/mass spectroscopy.

We report a sensitive, rapid, quantitative gas chromatographic/mass spectroscopic method for measuring the 6-monoacetylmorphine (6-MAM) metabolite of heroin in 0.5 mL of human urine. After a simple liquid-liquid extraction and derivatization, the trimethylsilyl derivative of 6-MAM is identified from its retention time (total ion current) and by selected ion monitoring. The limit of detection was 10 micrograms/L, corresponding to 0.2 ng of trimethylsilyl-6-MAM injected into the gas chromatograph/mass spectrometer. The presence of 6-MAM in urine is indicative of heroin. 6-MAM is not present in poppy seeds or in urine after the ingestion of products containing poppy seed.