Epidemiological studies have reported that airborne particulate matter (PM) is closely linked to adverse health effects including the prevalence of asthma and cardiovascular mortality. Recent epidemiological evidence suggests that airborne nanoparticles, particles smaller than 100 nm in aerodynamic diameter, have more significant toxicological implications than larger particles because their small sizes facilitate translocation to the brain and extra-pulmonary tissues, and can result in oxidative stress-induced DNA damage. The bulk of human exposure to nanoparticles occurs in periodic bursts indoors through combustion, high temperature processes, and consumer products. Such indoor nanoparticle sources are of increasing concern due to 1) their proximity to humans in a relatively small volume of an enclosed space; 2) relatively long hours spent indoors for Americans compared to outdoors. Yet, our understanding of morphology and composition and their effects on human exposure is limited.
We propose to characterize indoor nanoparticle sources in terms of their morphology, chemical composition, and size-resolved number concentrations. We will investigate the composition, morphology, and time dependent size distributions of nanoparticles generated from three sources (candle, hairdryer, electric stove) in a full-scale test building that serves as a research facility for the study of indoor air pollution. Along with field measurements, we will develop an analytical model for the fate and transport of nanoparticles in indoor air based on these experimental results. A combined composition, size, and morphology-resolved characterization of nanoparticles indoors will provide a comprehensive and useful dataset for the broader scientific community.
