Optimal conditions for the removal of house dust mite, dog dander, and pollen allergens using mechanical laundry

Background: Mechanical laundry is an effective tool for the environmental control of allergens, but the optimal conditions for removing allergens are not yet clear. Objective: To evaluate the optimal conditions of mechanical laundry for the removal of house dust mite (HDM), dog dander, and pollen allergens. Methods: The 4 washing modes of 30°C (86°F), 40°C (104°F), 60°C (140°F), and steam water (SW) with detergent were evaluated. Allergen removal performance was assayed using a 2-site enzyme-linked immunosorbent assay (ELISA) or an ELISA inhibition test. Results: Using the 30°C and 40°C washing modes, only 6.5% and 9.6% of Dermatophagoides farinae, respectively, were killed. However, using the 60°C and SW washing modes, all HDMs were killed. The amounts of Der f 1 remaining after the 30°C, 40°C, 60°C, and SW washing modes were 26.8%, 2.4%, 1.3%, and 0.6%, respectively, with unmanipulated contaminated sheets. The effects of rinse on Der f 1 levels after the 30°C washing were greater compared with those after the 40°C, 60°C, and SW modes. The amounts of Can f 1 in the extractions after washing were 0.3% to 1.3% for all modes, and all extracts, even without a rinse, did not inhibit specific IgE binding to dog allergens according to ELISA. The remaining pollen allergen levels after washing were lower in the 60°C and SW modes than in the lower temperature modes. However, the levels did not differ among the various washing modes after rinsing once. Conclusion: Water temperature and number of rinses are critical factors for the removal of HDM, dog dander, and pollen allergens.