Assessment of Indoor Bioaerosols in Public Spaces by Real-Time Measured Airborne Particles

Abstract

Humans spend a considerable amount of time indoors, and indoor biological airborne pollutants may harm human health. Active bioaerosol samplers and conventional microbiological culture methods, which are widely applied in studies of airborne microbial contamination, are not only unable to perform continuous monitoring over long periods, but are also time-consuming and expensive. In order to rapid assess indoor airborne microbial contamination, multiple linear regression models were constructed by statistically analyzing the measured bioaerosol samples and the real-time measured mass and number concentrations of airborne particles using a direct reading instrument from 43 air-conditioned public spaces. There were significant positive correlations of indoor airborne bacterial and fungal concentrations with indoor sizesegregated particle mass and number concentrations. The predictive power of the model was sufficient for predicting indoor bacterial concentrations from the indoor and outdoor size-segregated particle number concentrations as independent variables. Particle number concentration outperforms particle mass concentration as an independent variable in predicting indoor bioaerosol concentrations. The prediction model for indoor bacterial bioaerosol levels constructed in this study could facilitate a rapid assessment of potential airborne bacterial contamination via the simple and feasible measurement of particle number concentration, thus helping to improve the management and maintenance of indoor air quality.

Prediction Model for Airborne Microorganisms Using Particle Number Concentration as Surrogate Markers in Hospital Environment

“…Several studies reported a correlation between bioaerosol levels and particulate matter concentration, but some conflicting studies found no correlation [ 11 ]. We presume that the inconsistencies arise from differences in the methods used to measure particulate matter.…”

“…Subsequently, the remaining 10% of the samples (test set) were used to validate the regression model. We also used standard statistical forecasting to obtain the mean absolute percentage error (MAPE), which explains the power of the MLR model for predicting the indoor bioaerosol concentration related to size-segregated particle number [ 11 ].…”

“…Previous studies attempted to evaluate the predictability of bioaerosol concentration using real-time particle counting, which is faster and simpler than culture-based measurement of microbes in the air. The results have been inconsistent: while some studies showed a significant correlation between particle number and biological aerosol [ 2 , 8 , 11 ], others demonstrated no correlation [ 10 , 12 ]. In addition, most studies have focused only on the operating room and intensive care unit (ICU) [ 9 , 12 , 13 ], and a few studies have investigated other wards of the hospital [ 8 ].…”

Variation of Bacterial and Fungal Community Structures in PM2.5 Collected during the 2014 APEC Summit Periods

“…Gao et al (2015a, b) showed that the concentration of viable bioaerosols decreased with increasing haze severity in Beijing city. However, Huang et al (2017) showed that airborne bacterial and fungal concentrations were positive correlated with particle mass and number concentrations. Li et al (2015) suggested that bioaerosols exhibited higher concentration on hazy days than on non-hazy days in Xi'an city.…”

The Effects of Outdoor Source on Pollution Characteristics and Dynamic Changes of Particulate Matter in an Office

“…With the rapid development of economy and the continuous improvement of living standards, people's requirements for indoor environment are not only confined to indoor thermal comfort but also placed on the indoor particle pollution, namely, indoor air quality. According to the relevant data, a majority of people spend 70∼90% of their time indoors, especially for the elderly people and the disabled man [1][2][3]. erefore, indoor air quality is directly related to the health of a human body [4,5].…”