Exogenous: 1-androstendiol, 1-androstendione, bolandiol, bolasterone, boldenone, boldione, calusterone, clostebol, danazol, dehydrochlormethyltestosterone, desoxymethyltestosterone, drostanolone,
ethylestrenol, fluoxymesterone, formebolone, furazabol, gestrinone, 4-hydroxytestosterone, mestanolone, mesterolone, metenolone, methandienone, methandriol, methasterone, methyldienolone, methyl-1-testosterone, methylnortestosterone, methyltrienolone, methyltestosterone, mibolerone, nandrolone, 19-norandrostenedione, norboletone, norclostebol, norethandrolone, oxabolone, oxandrolone, oxymesterone, oxymetholone, prostanozol, quinbolone, tanozolol, stenbolone, 1-testosterone, tetrahydrogestrinone, trenbolone
Although the trainer Mahmood Al Zarooni admitted that he had made a 'catastrophic error' by giving anabolic steroids like ethylestrenol and stanozolol to the horses, he, however said he did not realise that what he had done was against the rules as the horses involved were not racing at that time.
BHA director Adam Brickell said that ethylestrenol and stanozolol are anabolic steroids and are therefore prohibited substances under British rules of racing, at any time - either in training or racing.