Home Air in Agriculture- Pediatric Intervention (HAPI)

The primary goal of the HAPI project, made possible through El Proyecto Bienestar, is to reduce exposure to inflammatory agents and allergens in the homes of an environmental justice community of Latino children residing in an area of intense dairy and crop-based industrial agricultural production. Community-based participatory activities in the Yakima Valley, Washington State have identified pediatric asthma as a priority health concern for the community. This study addresses three highly underdeveloped components of asthma and environment research: the health of children with asthma living in communities with industrial-scale agricultural operations, asthma in a particularly vulnerable subpopulation of Latino farmworker children), and evidence-based intervention strategies in these populations.
Children with poorly controlled asthma aged six through twelve years, recruited through the Yakima Valley Farmworker Clinic, will be randomized to the clinic's usual asthma educational program or an enhanced version which includes two portable high-efficiency particulate air (HEPA/NH3) cleaners located in the child's sleeping area and living room. Children in the usual program group will receive HEPA/NH3 units after their study year. Children with asthma living near areas of high agricultural production experience high morbidity and our preliminary research find significant effects of ambient concentrations of fine particulate matter and ammonia. Yet children spend the majority of their time indoors. Studies conducted in urban settings demonstrate that indoor particulate matter (PM) influences asthma outcomes and HEPA cleaners can reduce indoor and ambient generated PM. Data on asthma in rural settings is sparse, and trials incorporating HEPA portable air cleaners are lacking. This study seeks to characterize key indoor pollutant exposures for 75 children with asthma who reside within 400 meters of crop production or dairy operations.


Principal Investigator: Catherine Karr, MD, PhD
Professor, Environmental and Occupational Health Sciences
University of Washington 
NIEHS 2015-2021
Partners and Advisories:
El Proyecto Bienestar
Yakima Valley Farmworkers Clinic

M. Rosbach. Asthma study hopes to improve disease management among Valley children. Yakima Herald. March 20, 2017.

Masterson E.E., Younglove L.B., Perez A., Torres E., Krenz J.E., Tchong French M.I., Riederer A.M., Sampson P.D., Metwali N., Min E., Jansen K.L., Aisenberg G., Babadi R.S., Farquhar S.A., Thorne P.S., Karr C.J. The home air in agriculture pediatric intervention (HAPI) trial: Rationale and methods. Contemp Clin Trials. 2020 Sep;96:106085

Riederer A.M., Krenz J.E., Tchong-French M.I., Torres E., Perez A., Younglove L.R., Jansen K.L., Hardie D.C., Farquhar S.A., Sampson P.D., Karr C.J. Effectiveness of portable HEPA air cleaners on reducing indoor PM2.5 and NH3 in an agricultural cohort of children with asthma: A randomized intervention trial. Indoor Air. 2020 Sep 29.

Resultados del estudio de HAPI