Comparison of Mold Populations in Water-Damaged Homes in Australia and the United States

Abstract

The goal of this study was to examine whether the Environmental Relative Moldiness Index (ERMI) scale created for United States (U.S.) homes was applicable in the assessment of mold contamination for Australian homes. Settled-dust samples were collected in south-eastern Australian homes (n=76) being investigated for possible waterdamage and mold contamination. The 36 ERMI molds were quantified in each sample using mold specific quantitative PCR (MSQPCR) and the ERMI value for each home calculated. These homes were then matched to homes in the U.S. with nearly identical ERMI values and the average log10 concentration of each of the 36 molds statistically compared. Most of the 36 ERMI molds were found in Australian water-damaged homes in comparable concentrations to ERMI-matched U.S. homes. The U.S. ERMI scale might provide reasonable estimates of mold contamination in water-damaged Australian homes.

This is the first study to apply the MSQPCR technology and ERMI metric to water–damaged homes in Australia. Of course, there are limitations to the study since it was based on a very small number of homes and only homes in the south-eastern part of Australia (Figure 1). A national sampling of Australian homes, as was done in the U.S.  and the creation of an Australian ERMI should improve our ability to quantify mold contamination in Australian homes and any possible links to the high prevalence of asthma in Australia. It is possible that fewer or different molds in an Australian-ERMI might improve the estimates of mold contamination in Australian homes. Until an Australian-ERMI is created, it appears that the ERMI value for a waterdamaged Australian home is comparable to the ERMI value for a water-damaged U.S. home.

Gianni Rossini¹, Neil V², Lark D³, Wymer L⁴ and Vesper S^4*

¹Southwest Research Institute, San Antonio, TX, USA

²Mycotox, Wickham, New South Wales, Australia

³Mould Lab, Unit 4/52 Industrial Drive Mayfield East, New South Wales, Australia

⁴United States Environmental Protection Agency, Cincinnati, OH, USA