Variability of house dust mite allergen exposure in dwellings.
The variability of repeated house dust mite (HDM) allergen determinations at the same site within 3-24 months was evaluated on previously collected samples. Between two and four repeated measurements of Der p 1, a major allergen of Dermatophagoides pteronyssinus and Der f 1, a major allergen of D. farinae, on 46 carpets and 31 mattresses were analyzed. In 90% of carpets and mattresses, HDM allergen concentrations were clinically relevant (at least one measurement >0.1 microg Der p 1 + Der f 1/g dust). The coefficients of variation (CVs) for allergen concentrations in repeated samples over time (55.3-82.0% for the two allergens in beds and carpets) were clearly greater than the CVs for multiple samples collected at the same time (4.0-32.6%). Determination of allergen mass per square meter of surface instead of concentration per gram of dust resulted in an even greater CV (72.3-86.7%). The 95% range of expected values was about 10-fold above and below the result of a single determination. We conclude that single determinations of HDM allergen in dust give very limited information about long-term exposure of an individual to the allergen. Repeated measurements are recommended. Studies of factors that affect HDM allergen exposure must be planned with appropriate sample sizes.
Hirsch
T
T
Children's Clinic, University Hospital, Dresden, Germany.
Kuhlisch
E
E
Soldan
W
W
Leupold
W
W
D016902:Air Pollution, Indoor / Q000032:analysis*; D000485:Allergens / Q000032:analysis*; D000818:Animals; D039741:Antigens, Dermatophagoides; D004781:Environmental Exposure / Q000032:analysis*; D005858:Germany; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D008925:Mites
D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins