Predictors of indoor dust mite and cockroach levels

by Brooks, J. Mark

Exposures to dust mite and cockroach indoor allergens are important environmental risk factors in allergic sensitization and the development and exacerbation of asthma. To determine the relationship of indoor allergen levels and residence characteristics, dust samples were collected from indoor surfaces in residences in the Birmingham, Alabama area. The dust samples were analyzed for specific dust mite (Der p 1 and Der f 1) and cockroach (Bla g 1) antigens, the results of which were used to represent the level of indoor allergen present in each residence. The presence, and in some cases the degree, of potential allergen-predicting characteristics of each residence were visually inspected and recorded on a checklist inspection sheet by trained inspectors. These determinants were studied by multivariate stepwise regression analysis. The results did not show any of the visually inspected residence characteristics to be significantly (?=0.05) related to dust mite allergen levels. The results did show the “Level of food/debris?” and “Evidence of roaches or rodents?” inspection items to be significantly related to cockroach allergen levels from kitchen floor dust. This relationship accounted for 30% of the variability in the allergen sample results. The results of this study and similar studies suggest that visually inspected residence characteristics may not be a good indication of the level of indoor allergens. Additional residence characteristics that could be determined by environmental conditions ii monitoring, historical information from residents, or owners and more intrusive investigation methods may be necessary to more accurately predict indoor allergen levels. iii