High Particulates (PM 2.5) Found in Secondhand Cannabis Smoke (SHCS)
Nguyen PK, Hammond SK. Fine Particulate Matter Exposure From Secondhand Cannabis Bong Smoking. JAMA Netw Open. 30 Mar 2022;5(3):e224744. “Secondhand cannabis smoke (SHCS) is a novel exposure source uncharacterized in homes but containing known health risk factors. Although 27% of young adults believe SHCS exposure is safe, cannabis smoke has several hundred toxic chemicals, carcinogens, and fine particulate matter (PM2.5), many at higher concentrations than tobacco smoke.”
“Levels of PM2.5 were measured before, during, and after 8 cannabis social-smoking sessions in one 20-m2 household living room…. After 15 minutes of smoking, the mean PM2.5 (570 μg/m3) was more than twice the US Environmental Protection Agency (EPA) hazardous air quality threshold (>250 μg/m3). If one assumes the exposure concentrations were at the mean levels observed, a single home smoking session with no other exposures would generate an estimated mean daily concentration (200 μg/m3) that greatly exceeds the average in cigarette-smoking homes (44 μg/m3), nonsmoking homes (15 μg/m3), and the US EPA daily standard (35 μg/m3).”
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2790510
Stephen Hamann
