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Geographic distribution of Environmental Relative Moldiness Index molds in USA homes

Stephen Vesper1, Jennie Wakefield, Peter Ashley

  • 1National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, OH 45268, USA. vesper.stephen@epa.gov

Journal of Environmental and Public Health
|July 22, 2011
PubMed
Abstract

Insights

This study mapped the distribution of 36 molds in the Environmental Relative Moldiness Index (ERMI) across the USA. Mold populations and ERMI values showed heterogeneous distribution, with no clear spatial patterns found.

Area of Science:

  • Environmental science
  • Microbiology
  • Public health

Background:

  • The Environmental Relative Moldiness Index (ERMI) quantifies mold levels in homes.
  • Understanding mold distribution is crucial for indoor air quality and health assessments.

Purpose of the Study:

  • To quantify and describe the geographical distribution of the 36 molds comprising the ERMI.
  • To identify spatial patterns in mold populations across the USA.

Main Methods:

  • Analysis of settled dust samples from the 2006 American Healthy Homes Survey using mold-specific quantitative PCR (MSQPCR).
  • Examination of individual mold species' geographical distribution.
  • Application of partitioning and disjoint variable clustering analyses.
  • Computation of First Principal Component (FPC) scores for mapping.

Main Results:

  • Partitioning analyses did not reveal valid, spatially systematic distributions for mold populations.
  • Disjoint variable clustering identified seven distinct mold clusters.
  • Significant heterogeneity in the distribution of the 36 molds and ERMI values was observed across the USA.

Conclusions:

  • The study failed to identify clear spatial partitioning for mold distribution based on the analyzed criteria.
  • Mold populations and ERMI values exhibit a heterogeneous geographical distribution within the USA.
  • Further research may be needed to understand the factors driving these observed mold distributions.

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