Indoor mold levels and current asthma among school-aged children in Saskatchewan, Canada

Indoor Air. 2017 Mar;27(2):311-319. doi: 10.1111/ina.12304. Epub 2016 May 27.


Current knowledge regarding the association between indoor mold exposures and asthma is still limited. The objective of this case-control study was to investigate the relationship between objectively measured indoor mold levels and current asthma among school-aged children. Parents completed a questionnaire survey of health history and home environmental conditions. Asthma cases had a history of doctor-diagnosed asthma or current wheeze without a cold in the past 12 months. Controls were age- and sex-matched to cases. Vacuumed dust samples were collected from the child's indoor play area and mattress. Samples were assessed for mold levels and quantified in colony-forming units (CFU). Sensitization to mold allergens was also determined by skin testing. Being a case was associated with family history of asthma, pet ownership, and mold allergy. Mold levels (CFU/m2 ) in the dust samples of children's mattress and play area floors were moderately correlated (r = 0.56; P < 0.05). High mold levels (≥30 000 CFU/m2 ) in dust samples from play [adjusted odds ratio (aOR) = 2.6; 95% CI: 1.03-6.43] and mattress (aOR) = 3.0; 95% CI: 1.11-8.00) areas were significantly associated with current asthma. In this study high levels of mold are a risk factor for asthma in children.

Keywords: Asthma; Atopy; Case-control study; Children; Fungal loads; Mold.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollution, Indoor / adverse effects
  • Air Pollution, Indoor / analysis*
  • Allergens / adverse effects
  • Allergens / analysis*
  • Asthma / epidemiology*
  • Asthma / etiology
  • Case-Control Studies
  • Child
  • Dust / analysis
  • Environmental Exposure / adverse effects
  • Environmental Exposure / analysis*
  • Female
  • Fungi / growth & development*
  • Housing
  • Humans
  • Male
  • Risk Factors
  • Saskatchewan / epidemiology


  • Allergens
  • Dust