AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Measurements of Fine and Ultrafine Particles Emitted by Marijuana Sources Indoors in a Residence
Wayne Ott, Kai-Chung Cheng, TONGKE ZHAO, Lance Wallace, Lynn M. Hildemann, Stanford University
Abstract Number: 354 Working Group: Indoor Aerosols
Abstract Ten states in the U.S. have legalized recreational marijuana, but few studies have been done measuring exposure to secondhand marijuana smoke in everyday settings. Popular ways to smoke marijuana include a glass pipe containing cannabis buds, a pre-rolled joint similar to a cigarette or cigar, a water pipe or bong, a vaping pen that vaporizes cannabis oil from a commercial cartridge, and a blunt, which is a hollowed out cigar filled with marijuana. All these marijuana sources produce PM2.5, which is also produced by conventional tobacco cigarettes and cigars and is of concern because of its possible health effects.
We conducted controlled experiments with a human smoker indoors in a 43 m3 residential bedroom using two TSI Piezobalances, two TSI AM510 SidePak monitors, and a pair of TSI Condensation Particle Counters. Unlike conventional cigarettes, marijuana is often smoked one puff at a time, with a time gap between puffs. Our initial results show indoor emissions from different methods of smoking marijuana ranged from 1.4 to 3.1 mg/puff, with a pre-rolled joint producing the largest emissions. Since marijuana joints come in many shapes and sizes, we compare a variety of different marijuana joints with conventional cigarettes. While a regular tobacco cigarette may produce less PM2.5 per puff than a marijuana joint, conventional cigarettes usually are smoked in a manner different from marijuana -- the puffs are repeated until the tobacco is used up, so a comparison of the two types of smoking should take this difference into account. We discuss the basic methodology used to calculate source strengths, emission rates, and decay rates in the room of a home, illustrating the methodology with experimental data. This is one of the first systematic measurement studies of the effect of marijuana use on indoor air quality.