Influence of housing characteristics on air infiltration of agricultural pesticides into farmworkers' homes

Agricultural pesticides can contaminate farmworkers' homes by track-in on shoes, clothes, and skin, as well as through air-infiltration from pesticide spray drift or wind-resuspension of contaminated soil particles from nearby fields. The objective of this exploratory study was to gain a better understanding of which housing characteristics are most strongly associated with agricultural pesticide levels in farmworkers' homes and whether they are more indicative of the track-in or air-infiltration pathway of pesticides into the home. Surveys that included housing characteristic questions were administered, and soil, outdoor air, and household dust were collected from 21 farmworker homes in Yuma County, Arizona, an agricultural community along the U.S.-Mexico border. Samples were analyzed for the following pesticides: bifenthrin, endosulfan, permethrin, pronamide, trifluralin, carbaryl, and DDT. Spearman correlation analysis and Fisher's exact test were performed to determine which parameters were most strongly associated with pesticide levels in the household dust, soil, and air. The number of window panes, increased cooling of the home, and distance to the nearest field were positively associated with pesticide detection in house dust. In addition, the distance to the nearest field was significantly associated with pesticide detection in air, and the total pounds of pesticides applied in Yuma the month prior to sampling was significantly associated with pesticide detection in soil. These results suggest that pesticides are potentially entering farmworkers' homes via air infiltration through windows and ventilation systems. Future interventions focusing on the air-infiltration pathway may be effective at decreasing pesticide levels in farmworkers' homes.