[Urinary nandrolone metabolites in antidoping control].

The French National Laboratory of the International Olympic Committee (IOC) has detected norandrosterone (NA) and noretiocholanolone (NE) in urine samples from several sportsmen. These two substances are known to be urinary metabolites after nandrolone intake. In such cases, the NA level is always higher than the Ne level. However, in the urine samples of sportsmen tested positive, the NE concentrations were systematically higher than the NA levels. We therefore searched for other steroid precursors (commercially available capsules or tablets of dehydroepiandrosterone, 4-androstenediol, 5-androstenediol, 4-androstenedione, 19-norandrostenediol and 19-norandrostenedione, also illegally used in France) which could lead to an excretion of NA and NE and to an inverted ratio of these metabolites.