Quote Originally Posted by GARN
Hot smoke activates chemicals in the PVC piping that in turn releases carcinogenic smoke. It's best not to use PVC. Copper will also react to the smoke and release cancer causing smoke.
copper does not react to smoke,when a flame is applied copper vaporizes,thats what that black film is,and not only are you inhaleing copper but many toxins are realeased during the combustion.