Airborne microplastic deposition at the Taj Mahal and Agra Fort India

This study presents qualitative evidence of airborne microplastic (MP) deposition at two World Heritage monuments in Agra, India—the Taj Mahal and Agra Fort—highlighting an emerging risk for heritage conservation in densely urban settings. Airborne dust collected by high-volume sampling was analysed using complementary techniques— Optical Microscopy, Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy with Energy-Dispersive X-ray spectroscopy (SEM–EDX), and X-ray Diffraction (XRD)—to verify polymer presence, morphology, and weathering features. Multiple polymers were confirmed, including polyethylene (PE), low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), and ethylene–vinyl acetate (EVA), with fibres predominating over fragments. Microscopy and SEM revealed surface cracking, roughness, and other photo-oxidative features that can enhance sorption of co-pollutants and facilitate microbial colonization, indicating that MPs deposited on marble and sandstone are not inert residues but potential accelerants of chemical, physical, and biological deterioration. While the present work establishes occurrence and material identity at both monuments, quantitative particle counts, size distributions, and deposition rates were beyond its exploratory scope and are identified as priorities for follow-up monitoring. Given the high visitor density and urban emissions in Agra, these findings underscore the need to integrate MP surveillance into preventive conservation and urban air-quality management to safeguard heritage fabric and reduce potential exposure pathways for workers and visitors.