Pathophysiological impacts of particulate matter exposure on respiratory health and emerging biomarkers for early...

Particulate matter (PM) is a significant and preventable environmental health hazard, closely associated with the initiation, progression, and exacerbation of respiratory diseases. The pathological effects of PM inhalation arise from the combined influence of its physicochemical properties and individual susceptibilities, triggering oxidative stress, inflammatory cascades, epithelial barrier disruption, and structural remodeling of lung tissue. This review synthesizes current knowledge on the compositional diversity and emission sources of PM, the underlying biological mechanisms of respiratory toxicity, and the emerging role of molecular biomarkers in early disease detection. Key biomarkers include inflammatory mediators such as IL-6 and TNF-α, oxidative stress indicators like 8-OHdG and MDA, epithelial injury markers including SP-D and CC16, and epigenetic regulators such as miRNA signatures and DNA methylation patterns. These biomarkers hold promise for identifying subclinical alterations in pulmonary function, enabling earlier intervention before irreversible damage occurs. However, progress is hindered by challenges in assay standardization, matrix-specific validation, and inter-individual variability. Advancing biomarker-based surveillance will require coordinated, multidisciplinary efforts integrating molecular biology, environmental toxicology, bioinformatics, and sensor technology. The integration of high-resolution biomarker science into environmental health frameworks offers transformative potential for predictive, preventive, and personalized strategies to mitigate the global burden of PM-related respiratory disease.