Acute cardiovascular biomarker responses to ambient PM2.5 and its constituents: A panel study on healthy retirees

Ambient fine particulate matter (PM 2.5 ) remains a environmental risk factor for cardiovascular disease (CVD). However, the specific roles of PM 2.5 and its chemical components in cardiovascular events and the underlying mechanisms have not been fully understood. This study aimed to unravel the associations of short-term exposure to PM 2.5 and its constituents with adverse cardiovascular outcomes. A panel study of healthy retirees was conducted and a linear mixed-effects model used to examine the relationships between PM 2.5 , its 18 chemical components, and key cardiovascular biomarkers. Primary outcomes included blood pressure (BP), heart rate (HR), heart rate variability (HRV), interleukin (IL)-6, IL-8, high-sensitivity C-reactive protein (hs-CRP), 8-hydroxy-2’-deoxyguanosine (8-OHdG), tissue-type plasminogen activator (t-PA), platelet monocyte aggregates (PMAs), endothelin-1 (ET-1), creatine kinase (CK), and lactate dehydrogenase (LDH). In addition, stratification by gender and glutathione S-transferase theta 1 ( GSTT1 ) polymorphism was performed. Results showed that short-term PM 2.5 exposure was significantly linked to increased systolic BP (SBP), mean arterial pressure (MAP), HR, IL-6, and ET-1, along with decreases in t-PA and HRV. Metallic components (Mn, Ni, As, Se, Rb, Sr, Mo, Sb, and Cs) and ionic components (F − , NO 3 − , PO 4 3− , and SO 4 2− ) were particularly associated with elevated BP and reduced HRV. Moreover, gender and GSTT1 polymorphism modified susceptibility to these cardiovascular effects. Overall, these findings suggest that short-term PM 2.5 exposure induces significant cardiovascular and biochemical changes in retirees, including elevated BP, HR, systemic inflammation, endothelial dysfunction, coagulation disturbances, and reduced HRV. PM 2.5 constituents and individual factors, such as gender and GSTT1 polymorphism, contribute to these effects. • Short-term PM 2.5 exposure adversely affects BP, HR and HRV. • Short-term PM 2.5 exposure was associated with IL-6, ET-1 and t-PA. • Specific components of PM 2.5 are positively related to BP and HRV. • Gender and GSTT1 gene mutations modify cardiovascular effects of PM 2.5 exposure.