Identification and Seasonal Distribution of Ambient Bioaerosols and Associated Meteorological Factors in Shahrekord, Iran

Bacterial and fungal bioaerosols play important roles in the atmosphere and have significant effects on human health. This study aimed at investigating the concentration of bioaerosols in ambient air in Shahrekord, Iran during two warm and cold seasons at three different points in 2019. Moreover, the effect of meteorological factors such as temperature, relative humidity, UV intensity, and wind speed and direction on bioaerosols were studied.

In this descriptive-analytical study, sampling of bioaerosols was conducted using Andersen single-stage sampler at a flow rate of 28.3 L/min for 5 min on Sabrod dextrose agar (SDA) and Tryptic Soy agar (TSA) media for bacterial and fungal bioaerosols, respectively.

The study showed that the concentration of fungal bioaerosols was higher than bacterial bioaerosols in warm and cold seasons. The predominant genera of bacteria in both seasons included Micrococcus luteus (21.35%), Pseudomonas aeruginosa (12.68%), Bacillus subtilis (10.14%), and Staphylococcus aureus (9.93%). The predominant genus of fungi were Cladosporium (41%), Alternaria (16%), and Aspergillus (11%). Correlation analysis showed a significant positive correlation between the concentration of bioaerosols and wind direction and relative humidity and a significant negative correlation between temperature, wind speed and UV intensity in warm season.

The predominant species of bioaerosols identified in this study were opportunistic pathogens and allergens which can threaten public health. So, monitoring of the concentration of airborne bioaerosols in cities is a vital key to assess the health effects of ambient air pollution.