Molecular composition and gas-particle partitioning of indoor cooking aerosol: Insights from a FIGAERO-CIMS and kinetic aerosol modeling

Organic aerosol emitted from cooking is a major concern for indoor air quality. During the House Observations of Microbial and Environmental Chemistry (HOMEChem) campaign, we simulated cooking, cleaning occupancy activities in realistic residential setting measured resulting gas- particle-phase emissions using High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer with Filter Inlet Gases Aerosols (FIGAERO-HR-ToF-CIMS). We identified ?480 molecular formulas compounds on cooking-centered days attributed them to potential sources including commercial, personal care products, occupancy. Compounds containing carbon, hydrogen, oxygen atoms only (CHO group) composed most CIMS-measured molar fraction at 74-85%, nitrogen-containing (CHNO being second largest contributor (12-19%). investigated volatility species based FIGAERO-CIMS data three ways: (1) maximum desorption temperature one-dimensional thermograms, Tmax, (2) calculating gas-particle partitioning, Fp, (3) corridor parameterization estimate saturation concentrations formulas. used kinetic multi-layer model interactions aerosols clouds (KM-GAP) calculate equilibration timescales found that under sampling conditions (T = 323 K), it can take up 14 seconds equilibrium be met, whereas residence times are approximately 3 seconds. The chemical diversity wide range volatilities sampled during events highlight importance understanding partitioning spaces where people spend their time.