Impact of Preexisting Particles' Type and Concentration on Phase Partitioning of Indoor Semivolatile Organic Compounds (SVOCs)

SOHYEON JEON, Karolina Cysneiros de Carvalho, Jhao-Hong Chen, Brent Williams, Washington University in St. Louis

     Abstract Number: 507
     Working Group: Indoor Aerosols

Abstract
Semivolatile organic compounds (SVOCs) significantly contribute to both gas and particle phase air pollutants in indoor air. They have a substantial impact on indoor air quality and human health. Indoor gas-phase SVOCs can be released in large amounts from household items and chemical products, as well as from organic films that form on surfaces due to occupant activities such as cooking, cleaning, and smoking. Once released into the air, indoor gas-phase SVOCs can partition to particles that either infiltrate from the outdoor environment or originate indoors from human activities. Therefore, the properties of preexisting particles can significantly affect the gas-particle phase partitioning of SVOCs. In this study, we investigate the impact of preexisting particles' type (inorganic and organic) and concentration on the phase partitioning of various SVOCs (e.g., alkanes, phthalates, and PAHs) using a chamber. The study utilizes an aerosol mass spectrometer (AMS), thermal desorption aerosol gas chromatography (TAGs), and a scanning mobility particle sizer (SMPS) to monitor online bulk chemical composition, molecular-level chemical composition, and size distribution changes during the phase partitioning of SVOCs. The aim of the study is to provide insights into the factors that influence the fate and transport of indoor SVOCs in the presence of preexisting particles.