HOUSE DUST MICROBIOTA: PROSPECT OF THE ASSESSMENT OF ALLERGENIC AND PYROGENIC LOADS

Abstract

Background. For people with hypersensitivity, the problem of allergenic and pyrogenic environmental load is of great importance. Material and methods. Hostel and apartment dust in Moscow was analyzed for bacteria and fungi by microbiological and molecular methods. Results. Aerobic and facultative anaerobic bacteria prevailed, numbers varying from 4.8×104 to 2.0×109 MPN/g of dust in hostels (Me=4.8×106 MPN/g) and from 3.0×104 to 1.0×109 of dust MPN/g in apartments (Me=3.8×106 MPN/g). Gram-positive bacteria were revealed in 100% of apartments and in 80% of hostels, Gram-negative, in 47% of apartments, and in 73% of hostels. 9 yeast species were isolated: Filobasidium wieringae, F.magnum, Papiliotrema flavescens, Vishniacozyma victoriae, Rhodotorula mucilaginosa, Debaryomyces hansenii, Candida parapsilosis, C.tropicalis, Meyerozyma guilliermondii. R.mucilaginosa dominated (34.5% and 33.4%). Candida spp. were more frequent in hostels, while Filobasidium spp., in apartments. Yeast cell number varied from 3.5×103 to 1.3×106 CFU/g of dust in hostels (Me=3.2×104 CFU/g), and from 2.3×103 to 2.5×106 CFU/g of dust in apartments (Me=3.3×104 CFU/g). 56 mycelial fungi species were revealed. Penicillium chrysogenum (100%), Aspergillus niger (100%), Rhizopus stolonifer (100%), A.ochraceus (80%), Mucor plumbeus (67%), P cyclopium (60%) were the most frequent in hostels. P.cyclopium (60%), P.chrysogenum (60%) were the most frequent in apartments. Mold concentration varied from 1.8×105 to 7.5×106 CFU/g of dust in hostels (Me=5.2×105 CFU/g) and from 3.3×103 to 2.3×105 CFU/g of dust in apartments (Me=4.0×104 CFU/g). Micromycetes complexes were similar in different hostels but differed in apartments. Discussion. The species diversity and CFU counts of microorganisms do not give the true values of the concentration of allergenic and pyrogenic compounds. Conclusion. We propose complex assessment involving identification of both allergenic and pyrogenic compounds and producers.