Brooke Wahlquist, Brigham Young University
Health
Exposure to the house dust mite (HDM) allergens Der p 1 and Der f 1 has been implicated in the development and exacerbation of asthma, the leading chronic disease among children in the U. S. Indoor relative humidity (RH) is the most important determinant of HDM growth in homes. HDM populations reach a maximum size at 85% RH but can survive at RH levels as low as 54 %. The RH in the commonly arid climate of the western U.S. is often below 55%, and as such, HDM exposure in these areas has not been viewed as a significant health concern. However, studies have shown that evaporative coolers, or “swamp coolers”, can increase indoor RH levels enough in arid climates to support HDM growth. In this study, we propose to evaluate the relationship between HDM allergen levels in the home and evaporative cooler use in 46 single family homes in Utah County. Homes will be recruited from among BYU employees based on the age of home as well as type of cooling system used (evaporative cooler (n = 23) vs. central air conditioning (n = 23)). Der p 1 and Der f 1 will be measured in homes by reservoir dust and area air sampling. Additionally, continuous RH measurements will be taken in the home over a 72-hour period in order to more fully characterize fluctuations in indoor humidity, and their relationship to HDM concentrations. Samples and RH measurements will be collected up to 3 times in each home over the course of 1 year. Samples will be analyzed in the laboratory using enzyme-linked immunosorbent assay (ELISA) to detect Der p 1 and Der f 1, and by polymerase chain reaction (PCR) to detect HDM DNA on air sample filters.