How long are anabolic steroids detectable in the human body?

Nandrolone is an anabolic steroid occurring naturally in the human body, albeit in small quantities. Nandrolone is most commonly sold commercially as its decanoate ester (Deca-Durabolin) and less commonly as a phenylpropionate ester (Durabolin). Nandrolone use is indirectly detectable in urine tests by testing for the presence of 19-norandrosterone, a metabolite of this molecule. The International Olympic Committee has set a limit of 2 ng per ml of urine as the upper limit, beyond which an athlete is suspected of doping.