Evaluation of microbial content of indoor air in hot arid climate

Abstract

Air quality, both indoor and outdoor, is closely linked to a range of diseases, including respiratory, cardiovascular and vascular diseases. Therefore, indoor air pollution becomes a very important factor affecting the human health. A study was carried to evaluate the microbial content of indoor pollution in Al-Obour city in the hot arid climate of Greater Cairo, Egypt. Dust fallout samples were collected during year seasons in 2015 from three different sites according to traffic congestion from tested locations. Two parallel samples were taken from indoor and outdoor in all the studied points for comparison. The obtained results show that the number of different microorganisms in all dust samples was higher in the spring season as well as in the first months of the summer compared to winter or autumn seasons in different locations. It is worthy to state that the higher microbial content in falling dust samples was always associated with the high traffic effects from tested points. The higher microbial content was recorded in industrial district compared to other sites of living districts. In addition, microbial content was always higher in indoor samples compared to outdoor samples. Spore-forming bacteria were more common, followed by Staphylococcus, while the least value was reported by Pseudomonas aeruginosa. The predominant fungi genera were Ascospore followed by Cladosporium, Aspergillus/Penicillium. It should increase the application of phytoremediation technology for CO2 mitigation. On the other hand, various factories should be transferred outside the scope of residential blocs, especially in cities with high population density.