Let's not forget here that to test positive, you have to be over 50 ng (nanograms) of THC metabolites per ml (milliliter) of urine. That is way beyond the amount to make a second hand smoke claim credible. The NFL recently doubled their threshold for a positive test, bringing it up to the DOT level mentioned above. Just because something is detectable for a short time after ingestion, doesn't mean it will result in a positive test.