Dominant volatile organic compounds (VOCs) measured at four Cannabis growing facilities: Pilot study results

In recent years, sale of recreational marijuana products has been permitted in several states and countries resulting in rapid growth of the commercial cannabis cultivation and processing industry. As previous research has shown, biogenic volatile organic compounds (BVOCs) emitted from plants can react with other urban air constituents (e.g., NOx, HO radical) and thus negatively affect regional air quality. In this pilot study, BVOC emissions from Cannabis plants were analyzed at four grow facilities. The concentrations of measured BVOCs inside the facilities were between 110 and 5,500 μg m^-3. One adult Cannabis plant emits hundreds of micrograms of BVOCs per day and thus can trigger the formation of tropospheric ozone (approximately 2.6 g day^-1 plant^-1) and other toxic air pollutants. In addition, high concentrations of butane (1,080- 43,000 μg m^-3), another reactive VOC, were observed at the facilities equipped with Cannabis oil extraction stations. Implications: High concentrations of VOCs emitted from Cannabis grow facilities can lead to the formation of ozone, secondary VOCs (e.g., formaldehyde and acrolein), and particulate matter. Our results highlight that further assessment of VOC emissions from Cannabis facilities is needed, and this assessment is one of the key factors for developing policies for optimal air pollution control.