The major urinary metabolites of testosterone are androsterone glucuronide and etiocholanolone glucuronide. Silva's team was unable to explain the presence of androsterone in the 9 January test. Silva's team was unable to explain the presence of androsterone in the Jan 9 test. Silva's team was unable to explain the presence of androsterone in the Jan. 9 test. The same day, Iraqi weightlifter Mohammed al Aifuri tested for positive for etiocholanolone and androsterone. In 2013 Calja was suspended for two years for using androsterone. The result did not stand, however, as Sun failed a drugs test for androsterone. It is excreted mainly as androsterone glucuronide and etiocholanolone glucuronide. Spectrometric studies identify androsterone as the main backdoor androgen in the human male fetus. ADT-G is formed from androsterone by UDP-glucuronosyltransferases, with the major enzymes being UGT2B15 and UGT2B17. Androsterone has been found to affect human behavior when smelled. Androsterone is a metabolite of testosterone and dihydrotestosterone (DHT). Androsterone was first isolated in 1931, by Adolf Friedrich Johann Butenandt and Kurt Tscherning. Androsterone is found in the human axilla and skin as well as in the urine.