The secondhand smoke discussion is a good topic derailment for marijuana legalization. People will argue about that issue instead of just thinking about ways to consume it without exposing others to harm, such as going outside or any of the non-smoking ways to consume cannabis.
Second-hand smoke is an actual risk, but the studies that WHO cite all consider indoor use. Burning carcinogens should simply never be done without adequate ventilation, whether for food preparation, science experiments, or recreation.
http://www.who.int/tobacco/research/secondhand_smoke/about/e...
It's also misdirection to suggest carbon monoxide is dangerous in the same way as smoke is.
Research has shown that the volume of airflow needed to be mitigate the second hand smoke risk in at-risk workers is not met by any establishments, nor is it likely to be (because it's huge) - http://www.tcsg.org/sfelp/FedOHSHAets.pdf. https://www.cdc.gov/tobacco/data_statistics/fact_sheets/seco....
So please tell me, what "extremely effective" mitigations exist? Does anyone implement them in the workplace?
I don't like secondhand smoke, and studies are clear about its harmfulness. Nobody in this entire thread is advocating burning carcinogens indoors.
The effective mitigations (not sure why you used scare quotes) are
1. Burning carcinogens outside
2. Accomplishing the goal without burning carcinogens, e.g. ingesting chemicals through oral consumption or vaporization.
Not to argue against your point; i'm a little confused why one would argue FOR second hand smoke. In any circumstance with smoke.
Until then, "marijuana is better than tobacco" is simply a bullshit statement. Smoke less cigarettes and your risk of cancer and respiratory diseases will of course be lower!
That sources this study:
http://nationalacademies.org/hmd/~/media/Files/Report%20File...
That study states that "there is moderate evidence that there is no statistical evidence for ... lung cancer".
Now most studies in this area make mention of the fact that even for heavy marijuana smokers, they never smoke as much as a pack a day cigarette smoker. Which is to say, that even though there is more tar in the smoke of marijuana per gram, people don't smoke as much because they don't feel a need to.
That does not mean it is safe, but there is no evidence that it's as bad a cigarettes.
Just because something is dangerous at a certain exposure does not make it dangerous at all exposure levels.
Failing to highlight this difference is what separates FUD from actual science.