Abstract View
Exposure to Marijuana and e-Cigarette Aerosol in a Home
LANCE WALLACE, US EPA (retired)
Abstract Number: 210
Working Group: Aerosol Exposure
Abstract
Vaping, either marijuana or e-cigarettes, is rapidly growing in popularity worldwide. Secondhand exposure to the aerosols from vaping was studied for more than a year in an experimental room within a home. Research-grade monitors such as the SidePak (TSI Inc) and the Piezobalance (Kanomax) were employed together with a low-cost monitor (PurpleAir) to estimate the emission rates and decay rates of the aerosol.
Seven e-cigarette fluids ranging from 0-100% "VG" (vegetable glycerin) and "PG" (propylene glycol) were heated using a vaping pen and exhaled by a human vaper. Peak PM2.5 concentrations were high (1 mg/m3), but decay rates were extremely high and increased with time. About 88% of the exhaled aerosol was volatile and evaporated over a short time, so secondhand exposure was negligible. The Piezobalance recorded both the high initial concentration and over the next few hours also recorded the loss of particles from the crystal’s surface, a unique capability of this instrument.
Marijuana fluids ranging from 2:1 to 8:1 CBD/THC were heated in an electronic vaping pen either for 6 or 15 seconds producing PM2.5 emission rates of about 2.5 and 6.5 mg/puff, respectively. Peak concentrations were again high, volatility was low, and secondhand exposures were thus extensive. The decays were relatively slower compared to e-cigarettes.
The low-cost PurpleAir monitor performed well in relation to the research-grade monitors. An alternative method of calculating PM2.5 from the PurpleAir raw data performed better (higher precision, lower limit of detection) than the PM2.5 estimates provided by PurpleAir.