How are Non Combusted Cigarettes, Sometimes Called Heat Not Burn Products, Different from E Cigarettes and Cigarettes? FDA Difference between heated tobacco products and e cigarettes PMI Philip Morris International Where There's Vapor, Is There Fire? We Need Evidence on E Cigarettes RAND Vegetable glycerin and propylene glycol and the burning of dry coils. IQOS, Philip Morris's new heat not burn tobacco device, explained Vox