Indoor/outdoor particulate matter concentrations and microbial load in cultural heritage collections

A two-year study on UNESCO World Heritage Sites revealed that indoor particulate matter (PM) and microbial concentrations in cultural heritage collections often exceed outdoor levels, posing risks to organic materials. The research, conducted at coastal, urban, and mountainous locations—including the Historical Museum of Crete and the Neophytos Doukas Library—found that while closed showcases mitigated fungal exposure, specific bacteria, such as acid-producing and cellulose-metabolizing types, still penetrated these enclosures. Urban environments, like Athens, showed higher levels of heterotrophic bacteria, particularly in exhibits with mummified tissues. The study highlights the influence of indoor activities, anthropogenic emissions, and natural factors on air quality, emphasizing the need for targeted conservation strategies to protect vulnerable heritage collections.

Lazaridis, M., Katsivela, E., Kopanakis, I., Raisi, L., & Panagiaris, G. (2015). Indoor/outdoor particulate matter concentrations and microbial load in cultural heritage collections. Heritage Science, 3(1). https://doi.org/10.1186/s40494-015-0063-0