can you fail a drug test due to second hand smoke?
Yes and no. How much second hand smoke are you inhaling? Being around an occasional pot smoker is not going to lead to a failed drug test. If this were true most concert goers would not be able to get a job.
Inhaling second hand smoke from illegal drugs, such as marijuana, can cause you to fail a drug test. Any drugs that are absorbed into your blood stream will be detectable.