Geographic Distribution of Environmental Relative Moldiness Index Molds in USA Homes

Stephen Vesper,Jennie Wakefield,Gary Dewalt,Warren Friedman,David Cox,Peter Ashley

doi:10.1155/2011/242457

Abstract

Objective. The objective of this study was to quantify and describe the distribution of the 36 molds that make up the Environmental Relative Moldiness Index (ERMI). Materials and Methods. As part of the 2006 American Healthy Homes Survey, settled dust samples were analyzed by mold-specific quantitative PCR (MSQPCR) for the 36 ERMI molds. Each species' geographical distribution pattern was examined individually, followed by partitioning analysis in order to identify spatially meaningful patterns. For mapping, the 36 mold populations were divided into disjoint clusters on the basis of their standardized concentrations, and First Principal Component (FPC) scores were computed. Results and Conclusions. The partitioning analyses failed to uncover a valid partitioning that yielded compact, well-separated partitions with systematic spatial distributions, either on global or local criteria. Disjoint variable clustering resulted in seven mold clusters. The 36 molds and ERMI values themselves were found to be heterogeneously distributed across the United States of America (USA).

Highlights

Some attempts have been made to describe the geographic distribution of molds in United States of America (USA) homes and buildings
Horner et al [1] quantified culturable molds from air and dust samples obtained from 50 single family residences in Atlanta, GA, USA
These lists were validated by a modified listing process in which interviewers visited the sampled segments with the acquired lists to compare them with the housing units present to validate a list for each designated segment within each “primary sampling unit” (PSU)

Summary

Introduction

Some attempts have been made to describe the geographic distribution of molds in United States of America (USA) homes and buildings. Horner et al [1] quantified culturable molds from air and dust samples obtained from 50 single family residences in Atlanta, GA, USA. Shelton et al [2] reported on the analysis of culturable indoor and outdoor air samples from 1,717 buildings in the USA. 50% of the buildings were located in the “southeast” USA. These samples came from inspectors as part of their investigations of these buildings. These buildings did not represent a random sampling

Methods

Results

Conclusion