Characterization of reactive oxygen species (ROS) generated from secondary organic aerosols (SOAs) and their health implication
Abstract
Reactive oxygen species (ROS), present in particles or generated by particle components upon deposition of particles in the human lung, could cause negative health effects and is therefore a potentially important metric to quantify particle toxicity. We conducted a series of chamber experiments to investigate and compare the yields of ROS in secondary organic aerosols (SOA) from carene and cumene, representing biogenic and anthropogenic SOA precursors, respectively. The particle-bound ROS was quantified by a home-built online instrument using the DCFH-HRP assay. The role of NOx and relative humidity on ROS yield in these two SOA systems was investigated. The overall results show that (1) the presence of NOx during the photooxidation of the two precursors inhibited particle-bound ROS formation. (2) SOA produced from the photooxidation of carene had a higher ROS/SOA than that from the ozonylsis of carene. Correlations among online ROS, offline ROS and other gas-phase and particle-phase organics will also be discussed.
This study further examined the ability of the SOA particles generated in these chamber experiments to induce cell-based ROS production after exposing human lung epithelial cell lines (A549) to extracts of SOA. The correlation between exposed SOA extracts concentration and cellular ROS yields, and between acellular ROS concentration in SOA and cellular ROS yields were studied. The effects of SOA generated from different precursors and conditions on gene expression profiling of a broad range of oxidative stress and inflammation-associated genes in A549 cells were performed and the associated biological pathways were analyzed providing mechanistic insights into the potential health effects of SOA.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMGH41A..02Z
- Keywords:
-
- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0394 Instruments and techniques;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0240 Public health;
- GEOHEALTH