In one Q&A session during his campaign, Biden did note that as president he would ban e-cigarettes if the science demonstrated they were harmful, but left himself some wiggle room by declaring a studys not been fully done yet on this issue
3R4F smoked under conditions with turned on ventilation resulted in reduction of PM compared to those smoked without ventilation after 4.5 min (PM 10 :-47.5 to -58.4%, PM 2.5 :-47.2 to -58%, PM 1 :-39.6 to -50.2%) and after 10 min (PM 10 :-70.8 to -74.4%, PM 2.5 :-70.6 to -74.3%, PM 1 :-64.0 to -68.0%)
and the zones for the different processes that take place in the cigar during smoking, such as the combustion, pyrolysis, and condensation zones (references in the Further Reading section)
While commonly associated with cocaine, some users have reportedly used coke bullets with other powdered substances, including ketamine, MDMA in powder form, and even powdered caffeine or legal snuff tobacco