Chemical Characterization and Source Apportionment of Fine and Coarse Particulate Matter Inside the Refectory of Santa Maria Delle Grazie Church, Home of Leonardo Da Vinci’s “Last Supper”

A year-long study at the Church and Dominican Convent of Santa Maria delle Grazie in Milan revealed that indoor particulate matter (PM) concentrations were significantly lower than outdoor levels, with PM2.5 and PM2.5-10 reduced by 88% and 94%, respectively, primarily due to an effective ventilation system. While gasoline vehicles, urban soil, and wood smoke contributed minimally to indoor organic carbon (OC), fatty acids and squalane showed high indoor-to-outdoor concentration ratios, suggesting a dominant indoor source. This research highlights the role of both outdoor pollution infiltration and indoor emissions in affecting cultural heritage, offering insights for conservation strategies.

Daher, N., Ruprecht, A., Invernizzi, G., De Marco, C., Miller-Schulze, J., Heo, J. B., Shafer, M. M., Schauer, J. J., & Sioutas, C. (2011). Chemical Characterization and Source Apportionment of Fine and Coarse Particulate Matter Inside the Refectory of Santa Maria Delle Grazie Church, Home of Leonardo Da Vinci’s “Last Supper”. Environmental Science & Technology, 45(24), 10344–10353. https://doi.org/10.1021/es202736a