FACTORS AFFECTING THE RETENTION OF DUST-MITE ALLERGEN ON CARPET

Carpet is one of the most common and perhaps the most important reserv oir of aeroallergens and other components of dust found in residential or commercial settings. This research evaluated factors that affect t he retention of dust mite allergens on different types of tufted carpe t commonly found in homes and offices. Twenty-six types of carpet were custom manufactured as part of a two-stage factorial experiment using 182 carpet samples. Carpets differed with respect to fiber denier, cr oss-sectional shape, presence of fluorocarbon treatment, carpet style, pile height, and pile density. The major hypothesis tested was that t he amount of allergen-containing dust recovered from vacuum samples of tufted carpet sources was dependent on micro (fiber) or macro (constr uction) retention characteristics of the carpets. Carpet samples were doped in a uniform and reproducible manner using an allergen-containin g reference dust. A standardized vacuum surface sampler was used to re cover dust from samples. Allergen was assayed using a standard, monocl onal antibody ELISA. Carpet-surface area and presence of fluorocarbon were found to have the largest effects on retention and recovery of du st and allergen. Specifically, fluorocarbon treatment of fibers, squar e-hollow fiber shape, high-denier fiber, low-pile height in cut-pile c arpets, and low-pile density in loop carpets were significantly associ ated with increased release and recovery of allergen. Results from thi s study suggest that carpet type be considered for both allergen avoid ance and allergy and asthma risk assessment.