Air quality characterization in the Sanctuary of the Beata Vergine dei Miracoli in Saronno, Italy

The sanctuary of the Beata Vergine dei Miracoli is a marian sanctuary located in the small town of Saronno, in the province of Varese, Italy. According to the inscription carved on the door that once represented the entrance to the sanctuary and that now connects the church to the cloister, the laying of the first stone took place on May 8th 1498. Construction was completed in 1525, when Bernardino Luini and Alberto da Lodi received the commission for the frescoes in the main chapel and the anti-presbytery. Finally, Andrea da Milano was commissioned to create two large wooden scultpures ("Cenacolo" and "Compianto sul Cristo morto") to be placed in the two main internal chapels [1]. Throughout the years these statues have been restored several times, the last one in 1995. In view of the artistic richness of the Sanctuary, environmental monitoring is essential for the preventive conservation of the works of art in order to limit the deterioration phenomena linked to poor air quality. Moreover, the lack of regulations regarding the concentration of air pollutants in indoor spaces such as sanctuaries further highlights the importance of the issue.