Abstract Number: 399 Working Group: From Aerosol Dosimetry and Toxicology to Health
Abstract Numerous epidemiological studies have reported adverse health effects due to aerosols. In particular, allergic rhinitis and bronchial asthma in addition to cardiovascular diseases are seriously concerned. However, detailed mechanisms of the cellular biochemical reactions associated with the toxicity of aerosol particles have not been elucidated well so far. Cell exposure studies for aerosol particles have often been conducted using particulate matter collected by vibrating/scraping aerosol-loaded filters. However, the amount of particles that are collected on a filter is often insufficient to perform an exposure studies. In this study, a high-volume simultaneous sampler for fine and coarse aerosol particles was developed using the impactor and cyclone techniques. The newly developed instrument allows researchers to collect a sufficient amount of aerosol particles for exposure studies without using filters. We collected fine and coarse aerosol particles in three cities (Yokohama, Saitama, and Fukuoka) in Japan under the CYCLEX (Cyclone collection of PM followed by Exposure Experiments) project. Chemical analysis of the collected particles has been carried out for carbonaceous materials (EC and OC), water-soluble ionic species, metals, and PAHs, then followed by cellular exposure experiment. We found particle size- and sampling location-dependent response in the results of exposure experiments. Both fine and coarse particles collected at all locations decreased the viability of nasal epithelial cells and antigen presenting cells (APCs), increased the production of IL-6, IL-8, and IL-1β from bronchial epithelial cells and APCs, and induced expression of dendritic and epithelial cell (DEC) 205 on APCs. Several chemical components showed significant correlations to inflammatory responses or cytotoxicity. These results suggest that ambient fine and coarse particles differently affect upper and lower respiratory tract and immune response, which may depend on their diameter, the components, and other parameters caused by the difference in collection location.