Bacterial Community Specification in PM2.5 in Different Seasons in Xinxiang, Central China

In China, air pollution has become a significant environmental threat to human health in recent years. Airborne bacteria are critical constituents of microbial aerosols, which contain numerous pathogens. However, the effects of seasonal variations, environmental factors such as air pollution, and meteorological factors on microbial diversity are poorly understood. In this study, fine particulate matter (PM2.5) samples (n = 12) were collected using a high-volume air sampler over 24-hour periods during all four seasons from April 2017 to January 2018. Concurrently, the average daily concentrations of various air pollutants and the meteorological conditions were monitored. High-throughput sequencing of 16s rRNA was then employed to profile PM2.5 bacterial communities. The results showed that the bacterial communities varied significantly by season. Proteobacteria (35.5%), Firmicutes (23.0%), and Actinobacteria (16.2%) were the most abundant bacterial phyla in the PM2.5 samples. At the genus level, the diversity of the bacterial communities was significantly correlated with the ozone (O-3) concentration (r = 0.920, p = 0.001) and air temperature (T) (r = 0.534, p = 0.023). The results of this study can be used as a reference by other bioaerosol research that focuses on the health effects of atmospheric particulate matter.