Why the $%#! Does THC Stay in Your System So Long?
Just because you haven´t used marijuana in the last couple of days, does not mean that there will not be THC in your system. As mentioned above, the type of test also determines how long THC would be detectable in your system. Blood and saliva tests have the shortest detectable span, whereas urine tests can detect THC for up to 30 days in the system. Hair tests can detect THC for up to 3 months.