Impact of Indoor Sources of Emission on Ambient Air Quality

Indoor organic emissions are crucial regarding public health and air quality concerns. Many indoor emissions stem from solvent evaporation of volatile chemical products (VCPs), a broad class of sources emerging as a significant contributor to urban air pollution as emissions from classic sources like traffic has decreased over the last decades. Studying the effect of indoor physicochemical phenomena on emissions is warranted given the current knowledge gaps. Moreover, characterizing the transfer of indoor species to outdoor air impacting the ambient air quality is noteworthy. This work presents a chemically speciated VCP emission inventory for Canada. I found the modifying impact of indoor physicochemical phenomena was negligible for more than 95% of VCP emissions before their transfer to the outdoor space. Furthermore, my analyses revealed that more than half the total VCPs’ contribution to ambient OH reactivity and secondary organic aerosol formation in major urban areas in Canada between 2012 and 2017 originated from indoor spaces. My investigation of indoor-to-outdoor transport of gaseous emissions by analyzing inlet and exhaust streams of the mechanical ventilation system of a residence in downtown Toronto suggested buildings as critical net sources within urban regions. The calculated net building emission rates were comparable with indoor VCP emission predictions. Per the cannabis indoor air quality impacts, I modeled the distribution of tetrahydrocannabinol (THC) emitted from cannabis smoking among indoor compartments. The results showed that THC tends to accumulate on indoor upward-facing surfaces, leaving a small fraction of emissions airborne. I examined the involuntary exposure of passive indoor residents to THC and concluded adults and toddlers tend to uptake THC primarily through inhalation and non-dietary ingestion, respectively. I assessed strategies to mitigate exposure to THC and identified the measures targeting the airborne particles as the most efficient ones. Moreover, my field measurements of cannabis smoking and vaping emissions showed emissions with reduced reactivity and intermediate volatility are prone to be transferred by drug users to secondary indoor spaces. Overall, this work highlights the remarkable role of indoor sources in the whole budget of anthropogenic emissions and their relation to ambient air quality matters.

Department dc:contributor.department

Chemical Engineering Applied Chemistry

Year dc:date.issued

2024

Author dc:creator

• Askari, Amirashkan

Advisor dc:contributor.advisor

• Chan, Arthur AC

• Ambient Air Quality
• Atmospheric Chemistry
• Cannabis Smoking/Vaping
• Indoor Air
• Volatile Chemical Products
• Volatile Organic Compunds

Statement dc:rights

• Attribution-NonCommercial 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc/4.0/

Handle dc:identifier.uri

http://hdl.handle.net/1807/139931

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/139931