Decay of house-dust mite allergen Der f 1 at indoor climatic conditions
Authors: Sidenius, Kirsten E.1; Hallas, Thorkil E.1; Stenderup, Jørgen2; Poulsen, Lars K.1; Mosbech, Holger3
Source: Annals of Allergy, Asthma and Immunology, Volume 89, Number 1, July 2002 , pp. 34-37(4)
Publisher: American College of Allergy, Asthma, & Immunology
Abstract:
Background: The decay of house-dust mite allergens is important for the outcome of avoidance measures for house-dust mite-allergic patients. Objective: To quantify the stability of Der f 1 from mattress dust when exposed to domestic conditions. Methods: Three samples of mattress dust were individually homogenized and divided into 64 subsamples. Mites were killed by freezing for 48 hours at -30° C. The subsamples were exposed in eight homes, three storerooms, and one greenhouse, where temperature and relative humidity were recorded. Der f 1 was determined in extracts of subsamples (enzyme-linked immunoadsorbent assay) at 0, 3, 12, and 24 months. Results: In the three samples of mattress dust, the initial concentrations of Der f 1 (mean ± standard deviation; STD) were: 169 (12), 3.9 (0.4), and 31 (2.6)
g/g, respectively. Median half-life of Der f 1 in the mattress dust samples was 10 years in the exposure homes, 18 years in the store rooms, and 1.0 year in the greenhouse. No correlations among preserved Der f 1 and temperature, relative humidity, and absolute humidity in homes were found (Spearman rank correlation test). Conclusion: Natural decay of Der f 1, with an estimated half-life of 10 years at housing conditions, has no practical consequence in reducing allergen exposure. Therefore, avoidance measures should include an active removal of the allergens.
Document Type: Original article
Affiliations: 1: Allergy Unit, National University Hospital, Copenhagen, Denmark. 2: Mycology Laboratory, Statens Serum Institut, Copenhagen, Denmark. 3: Allergy Unit, Clinic B, Copenhagen University Hospital, Frederiksberg, Denmark.

Click here for Page Help