Mould in the Home Fact Sheet


Mould in the Home
Fact Sheet
Potential allergens such as pollen, mould sp ores and dust mite are commonplace in the daily environment and are found both inside and outside the home. Although most individuals are exposed tothese allergens on a regular basis with little impact on health, regular exposure to some allergens, particularly indoor moulds can cause severe health problems, especially when present in large quantities.
Fungi, or moulds, are an abundant group of micro-organisms that play a crucial role in the degradation process of organic matter and organisms in the envir onment. Approximately one quarter of the Earth’s biomass is made up of fungi and approximately 100,000 species of fungi have been identified.
Although moulds are fully functional in the outside environment, they can potentially pose a significant threat to health when transferred into the home.
How do moulds enter the home?
High numbers of microscopic airborne fungal spores are naturally found in outdoor air all year round and readily enter indoor environments through open windows and doors, vents and air conditioning systems.
They are also brought into people’s homes via clothing, bags, shoes and household pets. As a result,most moulds found inside the home e.g. Aspergillus and Penicillium are usually comprised of both outdoor and indoor fungal spores which can be found in
the soil of houseplants, dust, pets and household surfaces.
Once inside the home, fungal spores settle in a number of areas favourable to mould growth. Areas which provide warmth, moisture, a high level of humidity and a continual supply of organic matter and dirt, such as the bathroom and kitchen are prime locations. Activities such as drying laundry on indoor clothes driers or tumble dryers which are not vented to the outside can increase humidity levels in the home, consequently encouraging mould growth in the home. In addition, water damaged carpets, ceilings and walls in the home are prime sites for new growth if they are untreated and continue to remain damp.
Damp housing is a common problem across the globe, especially in areas of high humidity and is heavily associated with the presence of mould in the home, as well as an increase in the incidence of health problems.


How do household moulds cause health problems?
Not all household moulds cause health problems. However, some mould spores contain allergens, irritants and produce toxins which can cause health problems, especially when ingested or inhaled deep into the respiratory tract.


What health problems are related to household moulds?
Evidence to support a relationship between the presence of household mould or damp and an increase in the incidence of health problems such as fungal infections, respiratory illness, asthma and allergies is heavily documented.


Individuals with impaired immune functions such as the elderly, young children, cancer and HIV patients and patients who have received transplant organs are particularly susceptible to health problems caused by mould. As more and more of these patients are treated and rehabilitated in the home, it is increasingly important to ensure that secondary illnesses, such as those caused by mould exposure are prevented inthese individuals.