The Cytotoxic Effects of Fine Particulate Matter (PM_2.5) from Different Sources at the Air-Liquid Interface Exposure...

The health of humans has been negatively impacted by PM_2.5 exposure, but the chemical composition and toxicity of PM_2.5 might vary depending on its source. To investigate the toxic effects of particulate matter from different sources on lung epithelial cells (A549), PM_2.5 samples were collected from residential, industrial, and transportation areas in Nanjing, China. The chemical composition of PM_2.5 was analyzed, and toxicological experiments were conducted. The A549 cells were exposed using an air-liquid interface (ALI) exposure system, and the cytotoxic indicators of the cells were detected. The research results indicated that acute exposure to different sources of particulate matter at the air-liquid interface caused damage to the cells, induced the production of ROS, caused apoptosis, inflammatory damage, and DNA damage, with a dose-effect relationship. The content of heavy metals and PAHs in PM_2.5 from the traffic source was relatively high, and the toxic effect of the traffic-source samples on the cells was higher than that of the industrial- and residential-source samples. The cytotoxicity of particulate matter was mostly associated with water-soluble ions, carbon components, heavy metals, PAHs, and endotoxin, based on the analysis of the Pearson correlation. Oxidative stress played an important role in PM_2.5-induced biological toxicity.