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Characteristics of dwellings contaminated by moulds

Sandrine Roussel1, Gabriel Reboux, Anne-Pauline Bellanger

  • 1Department of Mycology, University Hospital of Besancon, France.

Journal of Environmental Monitoring : JEM
|June 6, 2008
PubMed

Insights

Indoor mould contamination is linked to unhealthy living conditions. Factors like ground floor location, high occupancy, electric heating, poor ventilation, and visible mould significantly increase airborne fungi concentrations.

Area of Science:

  • Environmental Health
  • Mycology
  • Indoor Air Quality

Background:

  • Moulds in dwellings are recognized as health hazards by occupants and authorities.
  • Understanding the toxic, allergic, and infectious risks of indoor moulds is crucial for public health.
  • Established thresholds for mould pathogenicity are still under investigation.

Purpose of the Study:

  • To identify dwelling characteristics associated with high concentrations of airborne fungi.
  • To statistically analyze factors contributing to indoor mould contamination.
  • To evaluate the effectiveness of visible mould and moisture odours as indicators of unhealthy housing.

Main Methods:

  • A comparative study of 128 dwellings in France (69 with reported mould/humidity issues, 59 controls).
  • Air sampling using an impactor in 500 rooms to quantify fungal concentrations.
  • Questionnaires and investigator assessments covering dwelling characteristics, occupant information, and mould indicators.
  • Measurement of indoor/outdoor temperature and indoor relative humidity.

Main Results:

  • Higher total airborne fungi concentrations were found in ground floor apartments.
  • Small, highly occupied dwellings showed increased mould levels.
  • Dwellings with electric heating, no ventilation, and water damage had significantly higher fungi counts.
  • Visible mould and moisture odours were strongly correlated with elevated airborne fungi (p < 0.001).

Conclusions:

  • Specific dwelling characteristics are significantly associated with increased indoor mould contamination.
  • Factors such as poor ventilation, water damage, and high occupancy contribute to unhealthy indoor environments.
  • Visible mould and moisture odours serve as effective indicators for assessing housing insalubrity.

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