PURPOSE: The effects of air cleaners on the removal of airborne indoor allergens, especially house dust mites (HDM), are still controversial. The objective of this study is to evaluate the effect of an air cleaner with an electrostatic filter on the removal of airborne mite allergens. MATERIALS AND METHODS: A dried HDM culture medium that contained mite body particles and excretions was dispersed in a chamber equipped with an electrostatic air cleaner. The number of airborne particles was recorded continuously by a dust spectrometer for 60 minutes. Airborne particles in the chamber were collected on a sampling filter at a flow rate of 10 L/min and the Der f 1 concentration in the filter extracts was measured by two-site ELISA. RESULTS: The air cleaner efficiently removed airborne HDM particles. The air cleaner removed airborne HDM particles (size 2-12.5 microm) 11.4 +/- 2.9 fold (cleaner operating for 15 minutes), 5.4 +/- 0.7 fold (cleaner operating for 30 minutes), and 2.4 +/- 0.2 fold (cleaner operating for 60 minutes) more than the removal of HDM particles by natural settle down. Removal kinetics differed according to the particle size of the airborne particles. The air cleaner decreased the concentration of Der f 1 in the extraction of airborne particles collected on the air sampling filter by 60.3%. CONCLUSION: The electrostatic air cleaner can remove airborne HDM allergens and may be useful as a supplementary environmental control tool for HDM sensitized respiratory allergic patients.
Air Pollution, Indoor/*analysis ; Allergens/analysis ; Animals ; Antigens, Dermatophagoides/*analysis/*immunology ; Culture Media/metabolism ; Dust/analysis/immunology ; Environment ; Environmental Monitoring/methods ; Enzyme-Linked Immunosorbent Assay/methods ; Filtration ; Humans ; Kinetics ; Mites ; Particle Size ; Static Electricity