Does damp and mould in homes harm health?

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1. 1

   Self-reported questionnaires to assess indoor home environmental exposures in asthma patients: a scoping review.

   BMC public health (Punyadasa et al.)Published Oct 21, 2024Checked Oct 4, 2026

   “36 studies (82%) were cross sectional, 35 (80%) had a sample size of greater than 1000 participants, and 29 (66%) were conducted in children. Most studies (86%, n = 38) had binary (yes/no) or multiple-choice responses. 25 studies (57%) included a recall period of 12 months. 32 studies (73%) had a response rate of greater than 50%. Dampness, biological exposures (e.g. mould), and second-hand tobacco smoke were the most assessed indoor home environmental exposures. Childhood asthma (54%, n = 24) and asthma symptoms (36%, n = 16) were the most examined asthma related outcomes. The exposure most associated with adverse asthma outcomes was exposure to damp (79%, n = 35). 13 studies (29%) had developed a self-reported instrument by adapting questions from previous studies and almost all instruments (n = 42 studies, 95%) had not been validated.ConclusionsThe scoping review did not identify a comprehensive, validated self-reported questionnaire for assessing indoor home environmental exposures in patients with asthma. There is need to develop and validate a robust but pragmatic self-reported instrument, incorporating the findings from this review.”

2. 2

   A longitudinal cohort study of damp and mouldy housing and children's respiratory health in Bradford, UK.

   Environmental pollution (Barking, Essex : 1987) (Clark et al.)Published May 14, 2026Checked Oct 4, 2026

   “Additional analyses were conducted amongst children who did not move house between survey years. A quarter (23%) of children lived with damp and/or mould in early childhood and 3% had mould in their bedrooms. In cross-sectional analyses, mould in the bedroom was significantly associated with a higher adjusted OR of wheeze in early childhood (age 3-5). Early-life exposure to all damp and mould indicators was significantly associated with an increased adjusted-IRR of new reported hay fever in later childhood (age 7-11) (range of IRRs: 1.42 - 1.96 for children who did not move house). Adjusted-IRRs for incident asthma indicated a positive association with damp/mould, but were not statistically significant, likely due to limited sample size reducing statistical power. Our findings are consistent with the broader literature highlighting that damp, and particularly mould, is a risk factor for respiratory illness and allergy in children. Housing and public health interventions aimed at reducing exposures, particularly in bedrooms, may enhance child health and wellbeing.”

3. 3

   Update of a systematic review on associations between environmental exposures and asthma control and exacerbations in young children.

   BMJ open (Docherty et al.)Published Aug 31, 2025Checked Oct 4, 2026

   “A meta-analysis was carried out for a subgroup of selected papers.ResultsThere were 20 339 papers screened and 110 were eligible, including 23 rated strong, 81 rated medium and 6 low quality. There were 17 systematic reviews and 7 randomised controlled trials (RCTs). In most observational studies, exposure to exhaled tobacco smoke or respiratory virus and increasing exposures to outdoor air pollutants (including particulate matter, nitrogen dioxide, traffic-related air pollution and dust storms), fungal spores or tree pollen were associated with increased risk of worsening asthma outcomes. RCTs to reduce indoor air exposures were done in small populations and, although often able to reduce exposures, only one intervention changed asthma outcomes.ConclusionsThe number of eligible papers has increased to 110 from 27 described in our 2014 review, and the quality of papers has also increased. While associations between exposures and worsening outcomes are increasingly consistent, what remains unclear is whether interventions, particularly for indoor air and diet, may improve outcomes.Prospero registration numberCRD42021290184.”

4. 4

   Indoor mold (Wikipedia)

   WikipediaPublished Sep 29, 2026Checked Oct 4, 2026

   “Indoor mold (American English) or indoor mould (British English), also referred to as mildew, is a fungal growth that develops on wet materials in interior spaces. Mold is a natural, ubiquitous part of the environment and plays an important part in nature by breaking down dead organic matter such as fallen leaves and dead trees; indoors, mold growth should be avoided as it can affect the structural integrity of buildings and pose potential health risks to susceptible individuals. Mold reproduces by means of tiny spores, which range in size from 1 to 40 microns. The spores are like seeds—but invisible to the naked eye—that float through the air and deposit on surfaces. When the temperature, moisture, and available nutrient conditions are correct, the spores can form into new mold colonies where they are deposited. There are many types of mold, but all require moisture and a food source for growth. Common indoor molds include Aspergillus, Cladosporium, Penicillium, and Stachybotrys chartarum, which contribute to respiratory issues and allergic reactions in sensitive individuals.”

5. 5

   Crowded housing, indoor environment and children's respiratory, allergic and general health in Sweden: a cross-sectional study.

   BMJ open (Eiffener et al.)Published Sep 23, 2025Checked Oct 4, 2026

   “Primary outcomes for children's health were asthma, airway problems, breathing difficulties, rhinitis symptoms, mould and mites allergy, pollen allergy, furred pet allergy and good general health.ResultsAbout one in five children lived in an overcrowded home. Factors from the indoor living environment such as perceived poor indoor air quality and mould were significantly associated with crowded housing. Moreover, children who lived in overcrowded conditions were less likely to report good general health than children in non-crowded households (OR 0.64, 95% CI 0.54 to 0.76). This association was even stronger in children with asthma (OR 0.51, 95% CI 0.34 to 0.77). Few significant associations were, however, observed with the respiratory and allergic health outcomes.ConclusionsCrowded housing is associated both with a poor indoor environment and with poorer general health in children. Children with asthma may experience even poorer general health.”