Particulate matter pollution: Characterization of bioaerosols in South Indian cities

Abstract

In the present study, we aimed to report biocomponents associated with airborne particulate matter (PM) collected from South Indian cities. PM-10 samples were collected from ambient air quality monitoring sites from Hyderabad (n=48) and Chennai city (n=44). We are reporting bioaerosols such as proteins, endotoxin, bacterial and fungal DNA concentration from these cities. Measurements have shown that average protein concentration was approximately 5.2% and 4.8% of the average PM mass concentration in the above cities. Our study showed that total bacterial DNA constitutes only a small fraction (0.1-0.01%) of total DNA associated with PM.However, the average fungal DNA concentration was approximately 8.6% and 3.7% of the total DNA concentration. We also found that, airborne endotoxin is significantly correlated with PM mass concentrations (p<0.001).In both cities, endotoxin was also found to be correlated with trace elements such as calcium (p<0.001). This may indicate that endotoxin might have originated from resuspended dust. Average carbohydrate concentration accounts for 2-4.3% of average PM mass concentration. Taking together, our study shows that biogenic particles are significant part of ambient PM.Also, our study emphasizes that components of biological origin could play a significant role in ambient PM induced adverse health effects and calls for thorough investigations into airborne biological components.