Isolation and Identification of Airborne Mold Species in a High-Rise Condominium in Malate, Manila, 2023

Abstract

Airborne molds are ubiquitous bioaerosols that are associated with poor air quality and respiratory health. Mold spores are rampant both indoors and outdoors, and while indoor airborne mold surveillance studies have previously been conducted, mold diversity and identity across floor levels in high-rise condominiums have not been done before. Therefore, this study aims to identify airborne molds in a high-rise condominium, determine mold diversity, and establish the relationship between mold diversity and abundance to floor level. Settle plate passive air sampling was utilized to isolate 299 mold colonies which were identified to belong to 10 distinct genera. Common indoor molds such as Aspergillus sp., Hormodendrum sp., Penicillium sp., Chrysonilia sp., and Chrysosporium sp. were detected across floor levels– which are known airborne contaminants with pervasive spores that had been extensively documented from indoor isolates. Diversity measured using Shannon-Wiener Index (H’) and Simpson’s Index (SI) revealed that the 16th floor had the highest mold diversity (H’ = 1.60, SI = 0.75) in both indices- with the 30th floor also having an SI of 0.75, while 34th floor had the lowest diversity values (H’ = 1.07 and SI = 0.56). No significant differences in diversity across floor levels signify that the samples are not considered diverse. The correlation of mold species diversity to floor level yielded no statistical significance (p>0.05), directly suggesting that mold diversity does not correlate with an increase in vertical stratification. Active air sampling and gene sequencing are recommended to improve the specificity of the study for future reference.