Yoshira Ornelas Van Horne

Environmental Health Sciences / Department of Community, Environment, and Policy / College of Public Health

Influence of household and housing factors on dust levels inside residencies near a legacy mine.
The potential for exposure to contaminants in dust through ingestion and inhalation is a concern for people living near hazardous waste sites. Dust can enter homes via soil track-in on shoes and air-infiltration of wind-resuspended particles. Although the concentration of contaminants in dust often cannot be reduced, exposure can be minimized by decreasing the level of in-home dust.  The objective of our study was to identify factors associated with dust levels in homes. Two separate dust measurements were taken from 34 homes near a legacy mine. The first was dust fall rate (μg/mm2 hr), which was collected by placing a 125-mm filter inside an open 1-gallon can and setting it inside a home for two weeks. The second metric was dust loading (g/m2), which was collected by vacuuming a square meter of flooring for five minutes. Surveys that included household and housing factor questions were administered to all 34 homes. We used classification and regression tree (CART) analyses to explore which household and housing factors were most strongly associated with dust levels inside homes. CART analyses were performed separately for ‘modifiable’ factors (e.g. flooring type, keeping pets inside, etc.) as well as ‘fixed’ factors that are not easily altered (e.g. distance to mine).  Modifiable factors that significantly influenced dust fall rate were having hard flooring inside and using doormats. Modifiable factors that significantly influenced dust loading were having hard flooring inside and paved landscaping outside. Fixed factors that significantly influenced dust fall rate and dust loading were age of home and distance to tailings. Future interventions should target these factors in order to decrease dust levels in homes and ultimately limit potential exposures to contaminants in the dust.