MEASUREMENT OF PRIMARY BIOLOGICAL AEROSOL RESPONSIBLE FOR THE ONSET OF RESPIRATORY DISEASES

Inhalation of bioaerosol produces non-specific symptoms such as irritative reactions, headache, and fatigue, and human health effects such as asthma, respiratory infections, conjunctivitis, urticaria and hypersensitivity pneumonitis. The dominant biological components of air are fungal spores, bacteria and bacterial spores, ubiquitous in outdoor air, but scarcely measured due to the inadequacy of measurement methods. The use of biomarkers as tool for the determination of fungal and bacterial contribute to bioaerosol has been often suggested. In this study ergosterol, arabitol and mannitol have been associated to fungal spores, muramic acid has been associated to bacteria and dipicolinic acid has been associated to bacterial spores, as tracers. In the present work, a new analytical chemical method for the determination of this biomarkers was developed and fungal and bacterial component of aerosol was studied in suburban/rural and in urban sites. Ergosterol, arabitol, mannitol, muramic acid and dipicolinic acid content in airborne particulate matter, even at different sizes, was determined. Literature conversion factors correlating muramic acid and dipicolinic acid masses to bacteria and bacterial spores masses were applied. Literature conversion factors and new conversion factors correlating ergosterol, arabitol, and mannitol masses to fungi mass were applied and compared each other. The fungal spore concentrations obtained were different depending on the marker utilized and we deduced that in tropical regions or in very humid regions arabitol and mannitol principally come from fungal spore, especially during wet seasons. On the contrary at our latitude, that is in our meteorological condition, and dominant vegetation type arabitol and mannitol major primary emission sources are biomass burning, sea spray and plants. Therefore we conclude that, depending on the sampling area, arabitol and mannitol can overestimate fungal spore concentrations in atmosphere. Ergosterol remains the only possible biomarker and the estimated fungal concentrations in particulate matter PM10.