The interplay between microplastics and respiratory viral diseases

Microplastics, recognised as pervasive environmental pollutants on a global scale, have been identified in various human organs. Inhalation is a primary exposure route for both microplastics and respiratory viruses, raising concerns about potential synergistic health hazards. This review synthetizes current understanding of the mechanisms underpinning their interactions, with a focus on the role of microplastics in facilitating viral entry, modulating host microenvironments through oxidative stress, inflammation, and compromised innate immunity, and enhancing viral invasion, replication, and transmission. Evidence shows that microplastics damage respiratory epithelium, generate reactive oxygen species, and trigger inflammation whilst dysregulating immune cells, worsening coronavirus and influenza virus infections, leading to more severe and prolonged lung damage. This review outlines recent progress in how microplastics influence susceptibility to and development of respiratory viral infections, offering a scientific basis for creating targeted environmental health strategies and enhancing research on viral resistance mechanisms.