Abstract

The concentration and quality of microbes in urban atmosphere may affect human health and environment. In recent years, interest in air microbiology has been focused on air sampling strategies, indoor-outdoor distribution of microbes and climatic influences on microbial population. The weekdays distribution of aeromicrobial load at public places is not well established. Moreover, the research on airborne bacteria is under-acknowledged in India. In this study, air microbial load was estimated at two locations, a public garden (PG) and traffic circle (TC) at Gwalior, Central India during weekdays. The average weekday bacterial concentration at TC was found significantly higher (7120.48 cfu/m³) than at PG (4804.76 cfu/m³). The distribution of bacteria during weekdays (Monday to Saturday) was interesting as significantly higher bacterial load was found at TC than at PG. However, on weekend that is on Sunday, significantly higher count was observed at PG than at TC. The average weekly fungal count over TC (776.19 cfu/m³) was also found higher than at PG (605.71 cfu/m³). During week days, fungi also exhibited almost the similar distribution pattern as of bacteria at both sites. The correlation analysis of microbial load with meteorological factors (temperature, humidity and wind speed) revealed statistically non-significant effect. The study indicated that weekday variation in microbial load is mainly affected by daily activities as compared to meteorological factors in urban environment.

Key words: Airborne, bacteria, fungi, weekday variation, meteorological factors.