> The National Academies of Sciences, Engineering, and Medicine (NASEM) study (2018) concluded that long-term cannabis smoking is substantially associated with increased respiratory symptoms (i.e., cough, phlegm, and wheeze) and more frequent chronic bronchitis episodes than experienced by non-smokers.

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> By contrast, recent outbreaks of respiratory illnesses associated with consumption of mostly unregulated Delta-9-tetrahydrocannabinol (THC)-containing vaping products have so far resulted in 2807 hospitalizations and 68 deaths in the United States, with additional cases being investigated in Canada (Centers for Disease Control and Prevention (CDC), 2020, Government of Canada, 2020).

> E-cigarette vapor contains many of the known harmful toxicants found in traditional cigarette smoke, such as formaldehyde, cadmium, and lead, though usually at a reduced percentage.[25]