Distribution of the house dust mite allergens Der f1 and Der p1 in carpets, mattresses and upholstered furniture

The house dust mites Dermatophagoides farinea und D. pteronyssinus are important sources of indoor allergens. The aim of the present study was to determine mite allergen exposure in German dwellings and to improve the data basis for recommendations concerning measures for allergene reduction. Altogether, 292 dust samples from carpets, mattresses and upholstered furniture from 48 dwellings and 2 hotels were taken using Dustscreen (TM) tubes connected to a standard vacuum cleaner. Dust samples were analyzed for house dust mite allergens Der f1 and Der p1 by sandwich ELISA (Indoor Biotechnologies). Both allergens were detected in all 48 dwellings. On average, Der f1 concentrations were higher compared to Der p1 Increased values for Der f1 and Der p1 were not correlated. There was an obvious difference in the spatial distribution of Der f1 and Der p1 concerning the carpets in dwellings. While Der p1 concentrations in living and sleeping rooms were in the same range, Der f1 concentrations were significantly reduced for living rooms compared to sleeping rooms. Mattresses contained higher amounts of both Der f1 and Der p1 than carpets. Additionally, the predominance of Der f1 over Der p1 was more pronounced in mattresses than in carpets. These observations indicate a preference of D. farinae for mattresses with a stronger tendency compared to D. pteronyssinus.