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Medical Effects of second hand smoke

  1. Jan 15, 2012 #1
    I have a question regarding second hand smoke and its dangers, I hope this is the right place to post it.

    I have been told how dangerous second hand cigarette smoke is, I have also been told that it is impossible to fail a urine test due to inhaling second hand MJ smoke. So which is it, second hand smoke is an efficient way to transfer toxins from one to another, or toxins cant be efficiently transported via second hand smoke? Or are there other reasons that I am overlooking why this is supposedly so?

    Thanks for any help.
  2. jcsd
  3. Jan 15, 2012 #2


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    There's really no difference between second hand smoke and being the primary inhaler, other than possibly how deeply the smoke is inhaled into your lungs (the primary smoker might take a much deeper breath to "enjoy" the smoke than the person exposed to second hand smoke who is trying to breathe more shallowly to avoid inhaling as much as possible). You're inhaling the combustion products, whether intentionally or secondarily. The only real difference is that the primary smoker would be exposed frequently, while the person exposed to secondary smoke might be getting a lighter dose over time from less frequent exposure...unless they are sharing a home with a smoker.
  4. Jan 15, 2012 #3
    Thanks, Moonbear. It seems I have been told wrongly, second hand MJ smoke could cause one to fail a urinalysis, I couldnt see how it could work in one case and not the other and I knew one of the fine members here would set it straight.
  5. Jan 15, 2012 #4


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    The issue here is probably dosage. For getting high from marijuana and having enough to test positive for the substance, you need a large dose of the psychoactive compounds in the smoke, which the second hand smoke probably would not be able to provide in most cases. In contrast, the health concerns with tobacco and marijuana come from exposure to the carcinogenic substances in the smoke which can have harmful effects even at low doses is the exposure is chronic.
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