Several cigarettes filters contain carbon surrounded by their filters to filter out impurity, without filter out nicotine due to carbon's chemical properties. My idea would be to place pieces of charcoal at the bottom of a smoking bong to filter out cancer cause agents. However, I have hear that inhaling charcoal granulates can be harmful to the lungs.

Answers:
Inhaling charcoal (or almost anything besides air) can be seriously desperate for you. Also, it would be worthwhile to point out that even the best filters for cigarrettes do not filter out everything explicitly bad for you. Also, it depends on the design of your bong whether or not a filter would even relief at all. So contained by short, no. Activated charcoal will not remove all of the toxins contained by smoke, and it might not remove any depending on your bong.

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What would stop the charcoal from catching on fire?

Anyone who have stoked a barbecue grill knows it's no fun to inhale charcoal smoke.

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If you are worried give or take a few getting cancer from smoking on any type of plant, you need to purely quit smoking. But can the charcoal be any worse than what us smokers but in are bodies anyways.

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