Atmospheric microfungal biopollution in city houses of hosur, a industrial city of Tamilnadu, India

Microfungi are the main source of aero-biopollution in extra and intramural environment of most of the places worldwide. Their occurrence in the environments leads to different allergenic diseases viz., allergic asthma, bronchitis, rhinitis, and hay fever in the atopic human beings. The present study is an attempt to record the incidence and seasonal periodicity of airborne fungal spores in indoors and outdoors of an industrial city house, Hosur, Tamilnadu by Petri-plate settlement method from October 2009 to September 2010. In qualitative and quantitative way, fungal spores considerably varied from indoors to outdoors as well as from season to season. Outdoor air harbored maximum fungal spores (54%) in comparison to indoor air (48%). Incidence of fungal species was predominated with more number of propagules during mid winter (December) and early rainy (July) periods in comparison to other months. Qualitatively, Aspergillus was found with the highest frequency and had eleven members i.e., A. awamori, A. fumigatus, A. niger, A. flavus, A. flavipes, A. nidulans, A. ochraceous, A. japonicus, A. terreus, A. versicolor and A. wentii, but quantitatively, Penicillium was isolated highest in its contribution to total CFUs followed by Aspergillus. Out of the 32 isolated fungal taxa, Aspergillus fumigatus, A. awamori, A. niger, Rhizopus stolonifer and Alternaria alternata were the predominant aeroallergens, which cause different types of respiratory/lung diseases in atopic human beings. In seasonal periodicity, winter contributedthe maximum spore load followed by rainy and summer was found with the least in harboring the spore mass in the indoors and outdoors. Alternaria alternata, which is accounted as a human allergen for sporosis inducer and an agent for hay fever and other pathologies, was also intermittently recorded. A few plant pathogenic, saprophytic, field and storage fungi were also recorded during the study period. Effect of meteorological parameters on the fungal spores in the dwelling atmosphere was significantly assessed by Pearson's correlation coefficient analysis.