Indoor air quality in elderly care centers: A multidisciplinary approach

Studying the indoor air quality (IAQ) of elderly care centers (ECCs) has important implications for ensuring residents' health and safety. This study involves a multidisciplinary analysis of chemical and microbiological pollutants, comfort parameters and potential pathogens in five ECCs to determine the IAQ in the spaces with the longest dwell time, dining room and TV room. In general, the average concentrations of CO, CH2O, and particles were greater in the dining rooms which can be attributed to the dining room's closer location to the kitchen. The layout of these areas plays a significant role, as facilities with kitchens that are not separated from the dining room exhibited poorer IAQ. Certain pathogenic-related microbes (e.g. Cutibacterium, Sphingomonas, Fusobacterium, Malassezia) were identified in air samples. In general, such genera were positively correlated with particles, CH2O and NO2 concentrations and decreased when air purification was applied. Bacterial community composition was similar among rooms and strongly depended on ECC and purification, suggesting that human occupants are the main source of airborne bacteria. Airborne fungal communities did not depend on ECC or air purification, but particles concentrations were the main explanatory variable for their composition in indoor environments. A moderate non-carcinogenic risk due to inhalation of CH2O (2.69) and PM2.5 (1.44) was observed in the studied ECCs, so natural ventilation is not sufficient to obtain adequate IAQ. The installation of supplementary ventilation systems or the use of air purifiers would be advisable to avoid health risk, especially considering the vulnerability of the residents.