Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study
As part of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigating the respiratory health impacts of traffic-related air pollutants on asthmatic children in Detroit, Michigan, residential dust samples were collected to quantify mold exposure. Settled dust samples were collected with MiTest™ samplers and analyzed on 112 asthmatic homes in Detroit using the Environmental Relative Moldiness Index (ERMI). ERMI is a unitless indicator of the relative amount of mold due to water damage in relation to ubiquitous mold species. To understand how representative the ERMI value from a single dust sample is of mold exposure over time, a subset of homes were sampled twice (1 to 7 months apart) and compared. In addition, within-home variability of mold exposure was examined, as well as a comparison of the dust from residential vacuum cleaner bags and the settled dust for a subset of homes. The average ERMI value for the settled dust samples from the NEXUS homes was 14.5 (ranging from -2.5 to 33.9), and 29 homes (26%) had ERMI values over 20, indicating a high level of mold contamination. Settled dust samples collected on repeated visits were well correlated (r=0.71) as were separate bedroom and living room samples (r=0.68). Vacuum bags were correlated to the settled dust sampler (r=0.58) but often underestimated water damage mold species. ERMI values tended to increase with the age of the home, and had similar variability for homes in each of the NEXUS traffic classification groups. Overall, the ERMI value provided a reproducible and representative measure of residential mold exposures for participants in the health study.
Kamal, A., J. Burke, S. Vesper, S. Batterman, A. Vette, C. Godwin, M. Chavez-Camarena, AND G. Norris. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH. Hindawi Publishing Corporation, New York, NY, 2014(261357):1-8, (2014).