Investigating the impact of cleaning product formulations on indoor air chemistry

Cleaning products are a ubiquitous source of volatile organic compounds (VOCs) indoors. The chemical complexity of VOC emissions and the subsequent secondary pollutant formation complicates quantifying their role in indoor air pollution, thus hampering informed changes in consumer attitudes, product manufacturing, and regulations. This thesis addresses this uncertainty by quantifying VOC emissions from various cleaning products, examining the formation of secondary pollutants, and investigating the impacts of compositional and environmental changes on indoor air chemistry. Analysis of 23 regular and green cleaners identified 317 VOCs, with monoterpenes being the most prevalent. Regular and green cleaners contained up to 8.6 and 25.0 mg/L monoterpenes, respectively. Simulations showed that green cleaners generally resulted in higher concentrations of formaldehyde and peroxyacetyl nitrates (PANs), though some regular cleaners produced disproportionately high secondary pollutant concentrations due to higher emissions of monoterpenes with a large k(O3). Room-scale cleaning experiments measured 1.3-8.9 mg VOCs per cleaning event, with limonene dominating the secondary chemistry. Substituting limonene with monoterpenes with a higher k(O3) increased formaldehyde and total PANs concentrations by up to 13% and 23%, respectively, while substitution with lower k(O3) monoterpenes increased organic nitrate formation by up to 68%. High air exchange rates and outdoor pollution levels increased secondary pollutant concentrations due to increased availability of oxidants and pollutants via infiltration. Indoor surfaces impacted indoor air chemistry through oxidant surface deposition and multi-phase chemistry. Simulations in a basic kitchen scenario showed that plastic and soft furnishings contributed most to \O3 deposition, while wood contributed most to secondary formaldehyde emissions. Evidence from these studies suggest that altering the formulation of cleaning products and the surface area and materials of indoor surfaces can help reduce exposure to hazardous secondary pollutants. Further mechanistic and toxicological studies will be required to inform changes in product composition and building conditions for improved indoor air quality.