Could you test positive on a drug test for being around only marijuana smoke?

Yes.: If marijuana smoke is in the air, you're breathing it. And, it is absorbed thru your lungs, even if the joint is not in your mouth. The dose is much higher for the one doing the toking, but often there is enough absorbed in nearby persons in a closed space to test positive. And a positive test can last a long time (up to 4wks depending on exposure). Best idea: step away if others are lighting up.

Yes: I've seen people who did not use it get into serious trouble from this. The tests are very sensitive and will pick amounts that can result just inhaling the stuff second-hand.