Higher mold levels found in in the deteriorated housing in the Sun Valley neighborhood of Denver, Colorado compared to other Denver housing and higher rates of health insurance claims for some diseases documented for the Sun Valley residents compared to other Denver residents.

The Sun Valley Homes public housing in Denver, Colorado (CO) will be replaced because of its deteriorated condition. Our goal was to document the mold contamination and particulate matter (PM2.5) concentrations in Sun Valley homes and the circulatory and respiratory health of Sun Valley compared to all Denver residents (total 2761 and 1,049,046, respectively) based on insurance claims data for 2015 to 2019. Mold contamination in Sun Valley homes (n = 49) was quantified using the Environmental Relative Moldiness Index (ERMI) scale. Indoor PM2.5 concentrations were measured in Sun Valley homes (n = 11) using time-integrated, filter-based samples and quantified using gravimetric analysis. Outdoor PM2.5 concentrations data were obtained from a near-by United States Environmental Protection Agency monitoring station. In Sun Valley homes, the average ERMI value was 5.25 compared to -1.25 for other Denver homes. The PM2.5 median concentration inside Sun Valley homes was 7.6 µg/m3 (interquartile range - 6.4 µg/m3). The ratio of indoor to outdoor concentrations of PM2.5 was 2.3 (interquartile range - 1.5). In the last five years, ischemic heart disease was significantly more likely for Denver compared to Sun Valley residents. However, acute upper respiratory infections, chronic lower respiratory diseases and asthma were all significantly more likely for Sun Valley than Denver residents. Since the process of replacing and occupying the new housing will take several years, the next phase of the study will not occur until that process is complete.