Insight into urban PM2.5 chemical composition and environmentally persistent free radicals attributed human lung epithelial cytotoxicity

• Published in: Ecotoxicology and environmental safety 2022-04, Vol.234, p.113356, Article 113356
• Main Authors: Li, Hanhan, Zhao, Zhen, Luo, Xiao-San, Fang, Guodong, Zhang, Dong, Pang, Yuting, Huang, Weijie, Mehmood, Tariq, Tang, Mingwei
• Format: Article
• Language: English
• Subjects: A549 cell; Chemical components; Cytotoxicity; Environmentally persistent free radicals (EPFRs); Fine particulate matters (PM2.5); Human health risk
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2022.113356

Fine particulate matter (PM2.5) is detrimental to the human respiratory system. However, the toxicity of PM2.5 and its associated potentially harmful species, notably novel pollutants like environmentally persistent free radicals (EPFRs), remains unclear. Therefore, one-year site monitoring and ambient air PM2.5 sampling in the Nanjing urban area was designed to investigate the relationships between chemical compositions (carbon fractions, metallic elements, and water-soluble ions) and EPFRs, and change in cytotoxicity with varying PM2.5 components. Oxidative stress (reactive oxygen species, ROS), inflammatory injury (IL-6 and TNF-α), and membrane injury (LDH) of human lung epithelial cells (A549) induced by PM2.5 were analyzed using in vitro cytotoxicity test. Both the composition and toxicity of PM2.5 from different seasons were compared. The average daily exposure of urban PM2.5 associated EPFRs load in Nanjing were 2.29 × 1011 spin m−3. Their exposure concentration and cytotoxic damage ability were stronger in the cold season than warm. The particle compositions of metals and carbon fractions were significantly positively correlated with EPFRs. The airborne EPFRs, organic carbon (OC), and heavy metal Cu, As, and Pb may pose principal cell damage ability, which is worthy of further study interlinking aerosol pollution and health risks. [Display omitted] •PM2.5 pollution in typical urban area is accompanied by the associated EPFRs exposure.•The overall exposure risk of bulk PM2.5 is related to both aerosol level and compositions.•PM2.5 loaded EPFRs were significantly positively correlated with metallic elements and carbon fractions.•Airborne EPFRs, organic carbon, and heavy metals may be pivotal cytotoxic components.•Cytotoxicity and pollution of PM2.5 and EPFRs are higher in cold than warm season.