Photochemical Aging of Gasoline Car- and Wood Combustion-Emissions Increase Adverse Effects in Air-Liquid Interface (ALI) Exposed Human Lung Cells
Svenja Offer, Hendryk Czech, Sebastiano Di Bucchianico, Mathilde Delaval, Sebastian Öder, Jana Pantzke, Johannes Becker, Anja Huber, Anni Hartikainen, Pasi Jalava, Mika Ihalainen, Pasi Yli-Pirilä, Olli Sippula, RALF ZIMMERMANN, Consortia ULTRHAS, Team aeroHEALTH, Mass Spectrometry Centre;Rostock University/Helmholtz Munich
Abstract Number: 266
Working Group: Health-Related Aerosols
Abstract
Emissions from traffic and residential wood combustion (RWC) substantially contribute to toxic particulate matter (PM2.5). In this study, we compare toxicological profiles of fresh and aged RWC- (combustion of spruce logs in a modern chimney stove) and car-emissions (dynamometer operated EURO 6d gasoline car). A flow tube reactor was used for photochemical aging of the emissions (~2 days OH.-exposure equivalence). For RWC-experiments, mice were exposed 3-times to fresh and aged RWC-emission aerosols for 4 hours. Simultaneously, murine macrophages were exposed at the air-liquid interface (ALI). For the aerosol-mediated toxicity, inflammatory, cyto- and genotoxic effects were as-sessed on the functional-, transcriptomic- and proteomic-level. Chemical/physical aerosol properties showed high re-producibility between experiments. Aging slightly increased particle mass but caused distinct changes in the particle chemical composition (e.g., in polycyclic aromatic hydrocarbons (PAHs), oxygenated-PAHs and nitrophenols). Ageing led to a drastic decrease in PAH-concentrations and a net increase in oxygenated-PAHs and nitrophenols. Toxicity-related outcomes were observed in vivo and in vitro after the exposure to either fresh (mild effects) or aged RWC-emissions (strong effects). At functional level, we found induced DNA-breaks in cells of the bronchial alveolar lavage as well as in RAW264.7-murine macrophages that have been exposed to fresh, but especially to aged RWC-emissions. No inflammation was observed in mice after the exposure to fresh RWC-emissions while aging of RWC-emissions led to a clear inflammatory response. For the EURO 6d car, the installed particle filter is precipitating particles with a very high efficiency. Accordingly, the fresh emissions only have a very small adverse impact on ALI-exposed human lung cells (A549/Beas2B). In the PEAR-aged emission, however, high concentrations of secondary particles are formed and reac-tive oxygenated species are present causing a strong increase of the observed toxic effects. Thus, the current emission control devices are not yet addressing secondary aerosol formation potential appropriately.