Bioaerosol concentration and health implication for children in daycare centers

Abstract

Indoor air quality in daycare center (DCCs) is a significant concern due to its potential impact on child health. Exposure to bioaerosols, including bacteria and fungi, can lead to respiratory infections, allergies, and other health issues. This study aims to assess the concentration of bioaerosol in DCCs, identify factors influencing their concentrations and I/O ratio. The bioaerosol sample was collected using bio stage impactor and Tryptic Soy Agar (TSA) and Sabouraud Dextrose Agar (SDA) agar as a collection media. The highest indoor bacteria and fungi concentration was recorded in Kotasas DCC (1668 CFU/m3) and Balok DCC (1706 CFU/m3), respectively. Both concentrations have exceeded the ICOP recommended limit which are 500 CFU/m3 and 1000 CFU/m3 for both bacteria and fungi. The I/O ratio for bioaerosols varied across daycare centers, indicating differences in ventilation efficiency and indoor contamination sources. Pekan and Kotasas DCCs showed high bacterial I/O ratios (5.88 and 3.07), suggesting poor ventilation, while Bukit Ubi DCC had nearly equal indoor and outdoor concentrations (I/O ≈ 1), reflecting effective air exchange. Relative humidity (RH) measured in the indoor and outdoor air ranged approximately from 60 to 83% while the temperature ranged from 26 °C to 32 °C. The statistical analyses were performed using Rstudio 4.4.1. Spearman’s correlation analysis revealed a strong positive correlation between indoor fungal concentrations and RH (p < 0.01, r = 0.71) but a negative correlation with temperature (p < 0.01, r = − 0.46) and occupancy (p < 0.01, r = − 0.52), while indoor bacterial levels showed a moderate positive correlation with occupancy (p < 0.01, r = 0.55). These findings highlight the significant impact of environmental factors and occupancy on indoor air quality in DCCs. By understanding these relationships, effective strategies can be implemented to improve ventilation systems, reduce bioaerosol levels, and create healthier indoor environments for children.