Indoor, outdoor, and personal exposure to PM2.5 and their bioreactivity among healthy residents of Hong Kong

• Published in: Environmental research Vol. 188; p. 109780
• Main Authors: Chen, Xiao-Cui, Chuang, Hsiao-Chi, Ward, Tony J., Tian, Linwei, Cao, Jun-Ji, Ho, Steven Sai-Hang, Lau, Ngar-Cheung, Hsiao, Ta-Chih, Yim, Steve HL, Ho, Kin-Fai
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2020
• Subjects: Biomarkers; Inflammation; Organic carbon; Oxidative stress; PAHs; Biomarkers; Organic carbon; Oxidative stress; PAHs; Inflammation
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2020.109780

Direct evidence about associations between fine particles (PM2.5) components and the corresponding PM2.5 bioreactivity at the individual level is limited. We conducted a panel study with repeated personal measurements involving 56 healthy residents in Hong Kong. Fractional exhaled nitric oxide (FeNO) levels were measured from these subjects. Out of 56 subjects, 27 (48.2%) participated in concurrent outdoor, indoor, and personal PM2.5 monitoring. Organic carbon (OC), elemental carbon (EC), particle bound-polycyclic aromatic hydrocarbons (PAHs), and phthalates were analyzed. Alteration in cell viability, lactic dehydrogenase (LDH), interleukin-6 (IL-6), and 8-isoprostane by 50 μg/mL PM2.5 extracts was determined in A549 cells in vitro. Moderate heterogeneities were shown in PM2.5 exposures and the corresponding PM2.5 bioreactivity across different sample types. Associations between the analyzed components and PM2.5 bioreactivity were assessed using the multiple regression models. Toxicological results revealed that indoor and personal exposure to OC as well as PAH compounds and their derivatives (e.g., Alkyl-PAHs, Oxy-PAHs) induced cell viability reduction and increase in levels of LDH, IL-6, and 8-isoprostane. Overall, OC in personal exposure played a dominant role in PM2.5-induced bioreactivity. Subsequently, we examined the associations of FeNO with IL-6 and 8-isoprostane levels using mixed-effects models. The results showed that per interquartile change in IL-6 and 8-isoprostane were associated with a 6.4% (p < 0.01) and 11.1% (p < 0.01) increase in FeNO levels, respectively. Our study explored the toxicological properties of chemical components in PM2.5 exposure, which suggested that residential indoors and personal OC and PAHs should be of great concern for human health. These findings indicated that further studies in inflammation and oxidative stress-related illnesses due to particle exposure would benefit from the assessment of in vitro PM2.5 bioreactivity. •Moderate heterogeneity in indoor, outdoor, and personal exposure to OC, EC, and PAHs compounds were observed.•OC in personal PM2.5 exposure plays a dominant role in cell viability reduction, cytotoxicity, and inflammation responses.•OC in indoor PM2.5 was more associated with cytotoxicity, inflammation responses, and oxidative stress.•Indoor and personal exposure to OC and PAHs exhibited associations with PM2.5 bioreactivity.•PM2.5-induced oxidative stress and inflammation (in vitro) were associated with changes in FeNO levels in adult subjects.