DEVELOPING ANTIBACTERIAL LIME MORTAR FOR SUSTAINABLE LIMESTONE CONSERVATION

The increasing focus on using compatible materials in architectural heritage conservation has renewed interest in lime-based mortar technologies. Challenges persist in optimizing lime slurry preparation and selecting suitable materials for restoration, such as slaked lime versus aged lime putty. A major concern in preserving ancient structures is microbial deterioration caused by bacteria and fungi. Since 2010, metal oxide nanoparticles (NPs)—notably titanium, silver, and zinc oxides—have been applied to protect building surfaces from biofilm formation. While these nanoparticles demonstrate strong antimicrobial activity, environmental toxicity remains a concern due to potential leaching into soil and water, which may impact non-target organisms. This underscores the need for updated testing protocols and standardized antimicrobial assessments to evaluate both biocidal efficacy and ecological safety. The study highlights the critical balance between effective microbial protection and environmental stewardship in heritage building conservation.