Norandrosterone and noretiocholanolone. Is this doping?

In order to evaluate the concentrations of norandrosterone (NA) and noretio cholanolone (NE) in human urine, nandrolone sulfate, nandrolone undecanoate , norandrostendiol and norandrostendione were administered, each to a diffe rent subject. The derivatized steroids were identified after pulsed mode injection by gas chromatography-mass spectrometry in electron impact mode, with selected io n monitoring. In the first case, NA and NE were detected in urine until 48 hours after or al administration of 22 mg of nandrolone sulfate. In the second case, urine specimens gave a positive response for NA and NE up to 8 months after intr amuscular injection of 50 mg of nandrolone undecanoate. Finally, NA and NE were detected for 8 days after oral administration of 50 mg and 100 mg of n orandrostendiol and norandrostendione. However, in contrast with nandrolone undecanoate, the ratio NA to NE was different according to the time of uri ne collection, after nandrolone, norandrostendiol and norandrostendione adm inistration. From about 60 urinary samples obtained from both standard population and at hletes, it was possible to characterize a physiological excretion of nandro lone metabolites. All concentrations were clearly under the proposed positi ve cutoff level (2 ng/ml) and the concentration of NA was always higher tha n the concentration of NE.