Home Air in Agriculture - Pediatric Intervention Trial (HAPI)

摘要

This university -community partnership identified poor air quality (particulate matter, ammonia) as a local risk factor for asthma morbidity among low income Hispanic farm worker children in a rural agricultural region of Washington State, USA. In response, a randomized trial was designed augmenting home-based asthma and environment education with placement of portable high efficiency particulate air (HEPA) cleaners containing a prefilter to reduce ammonia in the child's home. Using a rolling recruitment protocol, 30 of the total intended sample of 75 children have been recruited. All have poorly controlled asthma and live within 400 meters of crop production or dairy operations. Children participate for a one year follow up period with 2 week home indoor air contaminant measurement before randomization and approximately one year later. Asthma health is characterized twice prior and twice post randomization using both objective and subjective metrics. Validated questionnaires of asthma control, clinical utilization, exhaled nitric oxide concentration, spirometry, and urinary leukotriene concentrations are assessed. Enrolled children are all Hispanic, age 6-12 years and most (80%) are atopic based on positive skin prick testing to common aeroallergens. To date, the mean (SD) two week indoor sleeping area PM2.5 and PM10 concentrations observed are 11.8 (7.3) mcg/m3 (range 3.8-25.3) and 23.0 (13.3) mcg/m3 (range 6.7-43.9) respectively. Samples for analysis of indoor and outdoor NH3 have also been collected. Other common indoor asthma triggers of concern identified include rodent pests (69% of homes), use of irritant chemical cleaners (100% of homes), and wood burning for heat (25%). Community partners (Yakima Valley Farm Workers Clinic) and Northwest Community Education Center play a primary role in field based data collection of both health assessments and air sampling with training and oversight by University partners. Using a community engaged approach, this study is addressing a priority environmental health concern in a difficult to reach and understudied vulnerable population. Results will be incorporated into asthma education and management programs in the community.