Secondhand marijuana smoke and drug tests


I was at a party nine days ago, when my friends all started smoking pot. I didn't give in to the peer pressure. I didn't smoke any. But I did stay and hang around with them, and I think I got a little "contact buzz" from the second hand smoke. I'm in the military and have a random drug test tomorrow. Will second hand smoke show up in pee tests?? Please help me.

Thank You

Dear Reader,

The relationship between secondhand marijuana smoking and drug tests may seem a bit hazy, but research indicates that unless you were in a small room with poor ventilation (and you are tested shortly after exposure), the test results are usually negative. Although your “contact buzz” may have left traces of the chemical tetrahydrocannabinol (THC) in your urine, the amount is most likely not enough to fail a drug test. Most drug tests have intentionally high standards to avoid false positive results from incidental ingestion. To further ease your worries, testing positive from secondhand smoke tends to occur if you’re tested within hours of smoke exposure. Since your exposure took place nine days before being tested, you will most likely puff, puff, pass your drug test.

Interestingly, recent studies have shown that it’s possible to fail a drug test after exposure to secondhand marijuana smoke in small, unventilated spaces. However, these circumstances are uncommon in the real world as smoking usually takes place in fairly well ventilated conditions such as in rooms with air conditioning, by open windows, or outdoors. Avoiding smoke-filled cars, poorly ventilated rooms, and other enclosed smoky spaces may help ensure that you’ll still be clean for bugle call in the morning if you hang out with friends who are toking up.

Although you may be in the clear as far as drug tests go, secondhand smoke exposure has been linked to lung cancer and other respiratory conditions. You might want to check out the Go Ask Alice! Q&A Daddy-to-be smokes pot — Will it show up in baby-to-be? to find out more about the potential adverse health effects of secondhand marijuana smoke exposure.

Last updated Aug 28, 2015
Originally published Mar 20, 1998