A comparison of subject room dust with home vacuum dust for evaluation of dust-borne aeroallergens

Abstract

Background: Assessment of indoor allergen is valuable in exposure research and evaluation of allergic individuals. Collection methods range from grab vacuum samples to filtration devices located in the breathing range of an individual. For practical purposes, many research studies use analysis of collected house dust to evaluate allergen reservoirs.

Objective: To test the hypothesis that house dust collected from the family vacuum is equivalent to house dust collected by a technician following standard protocol.

Methods: Homes from a healthy homes demonstration project (n = 41) were sampled using a specific Department of Housing and Urban Development-suggested protocol in the bedroom of the child with asthma and a simple grab procedure from the family vacuum. Samples were evaluated for the presence of 5 allergens, Bla g2, Can f1, Der f1, and Der p1 combined as total mite, Fel d1, and Mus m1. Samples were also evaluated for total antigenic protein from 4 fungal taxa, including Alternaria, Aspergillus, Cladosporium, and Penicillium.

Results: All of the allergens and antigens tested showed good correlation between the 2 collection methods. Fungal antigens ranged up to 92,651 nanograms per gram of dust for Aspergillus, and allergens ranged up to 17,928 nanograms per gram of dust for Can f1. The best correlation was for Cladosporium (r = 0.91), and the weakest was for dust mite (r = 0.34).

Conclusion: Allergens and antigens tested from samples collected by protocol and by grab sampling from the home vacuum were highly positively correlated. Grab samples taken from the family vacuum may be a good surrogate for evaluating home allergen exposure.

Figure 1

Allergen measurements taken from the home vacuum grab sample and the child’s bedroom.

Figure 2

Correlation of allergen measurements using scatter diagrams. The home vacuum dust allergen measurement is plotted on the vertical axis, and the child’s bedroom dust allergen measurement is plotted on the horizontal axis. The Can f1 and Bla g2 allergens have the best correlation, whereas the combined dust mite (Der f1 + Der p1) measurements have a somewhat lower correlation.