In some cases, when the donor has used marijuana, a hair drug test, including HairConfirm™, may be unable to detect the THC metabolite due to the fact that the metabolite was unable to bind with the hair shaft. This can be caused by the type/quality of the marijuana smoked/ingested, or by what it has been mixed with, . tobacco. As a result, the result for marijuana may be negative. This is only the case with THC and not with the other illicit drugs (Cocaine, Heroin, etc). In most cases with adults it takes smoking 5-6 full joints in order for enough of the drug to “stick” to the hair to show a positive. (Please note: this is an average number.) If the amount consumed by the individual was less than that it might not show up in a drug test.
This is the scenario: a guy, say age 21, becomes serious about gaining muscle. He’s 5′ 10″, 7″ wrists, 9″ ankles, average genetics for muscle size-and-proportioned. He’s played sports, but never done more than an occasional resistance workout. Now, he begins a good training-eating-and-resting program. With his genetics, he has the potential for naturally gaining 45 pounds of lean mass if he stays consistent with progressive training/proper eating for a continuous 3 to 4 years.
But, about three months after beginning his training, he starts taking steroids. He does three steroid cycles in the following 18 months, and includes proper post-cycle therapy. That entire time, he’s continuing to consistently train and eat properly. Before the end of two years, he’s gained 45 pounds of lean mass (which with steroids, by the way, is not necessarily typical but neither improbable). At that point, he permanently quits using steroids, but he does continue properly training and eating for another two years. At the end of four years, he carries the same 45 pounds of lean mass.