Characterization of Mold and Moisture Indicators in the Home

Abstract

As studies increasingly support the presence of health risks associated with mold and moisture, understanding fungal concentrations and physical measurements as they relate to the microenvironment becomes more important. We conducted a cross-sectional study in the homes of 64 subjects. The primary objective of this study was to use trained inspectors' list of indicators in rooms (bathroom, bedroom, and basement) and determine whether these indicators are associated with higher fungal levels or physical measurements. A new category for combining the concentrations of fungal species, referred to as moisture indicator fungi (MIF), is used in the analysis. Our results show that basements with a musty odor, efflorescence, water sources, or mold have a two- to threefold increase in fungal concentrations over basements without these indicators. The regression model for the basement was highly predictive of indoor MIF concentrations (r² = .446, p = .017). Basement water sources are substantial predictors of indoor total fungi, MIF, and Aspergillus/Penicillium spp. MIF concentrations are higher in homes with basement water sources, and most notably, the increase in MIF concentrations is significant in other living spaces (bathroom and bedroom) of the dwelling. Basement water sources are important moisture/mold indicators for epidemiologists to use in exposure assessments performed in residential dwellings.

Keywords:

• basements
• exposure
• indoor
• moisture
• mold
• residential

ACKNOWLEDGMENTS

The authors wish to express a special thank you to the subjects who participated in this study. The authors sincerely appreciate the work by Solon Cole, Rocky Ackroyd, Lynn Wilcox, Robin Odell, Nyle Evans, and Joseph Burleson.

This work was supported by cooperative agreement R 825251 from the U.S. Environmental Protection Agency.

This work represents the views of the authors and does not imply endorsement by the Veterans Health Administration.

Notes

^A The difference between group means is statistically significant (p < .05) by independent sample t-test.

^B The sample size is 27 for present exhaust fan group for dew point temperature only.

^A n = number of homes.

^B A t statistic with its associated probability (approximate significance) was used to test that each measure differs significantly from 0. By using the kappa statistic as a measure of reproducibility, the p-values indicate the significant reproducibility between the SRQ and IRC.

^A The difference between group means is statistically significant (p < .05) by independent sample t-test.

^A The difference between group means is statistically significant (p < .05) by independent sample t-test.

^A The difference between group means is statistically significant (p < .05) by independent sample t-test.

^B The difference between group means approaches statistical significance (p < .07) by independent sample t-test.

^A Predictor variable in model A = outdoor concentrations.

^B Predictor variables in model B = outdoor concentrations and relative humidity.

^C Predictor variables in model C = outdoor concentrations, relative humidity, and moisture indicators.

^D Dichotomous variables (1 = yes, 0 = no).

^E p-value < .05.