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Is mould in the home bad for your health?

During the colder months you may notice an increase in damp and mould in your home. We find out if this can affect your health.

Charmaine Yabsley
July 2018

When cold, wet weather arrives, so can mould, appearing in unsightly patches on everything from walls to floors, clothes, shoes and in cupboards. Can it cause health issues for you and your family?

Mould and your health

Mould is a type of fungus that can be found both indoors and outdoors. It reproduces by making tiny particles called spores.

“Spores are carried in the air and may cause health problems if inhaled by people who are sensitive or allergic to them,” says Jeroen Douwes, professor of public health and director of the Centre for Public Health Research at Massey University, New Zealand.

Symptoms of a possible mould allergy include:

  • a running or blocked nose
  • irritated eyes
  • dry skin
  • sneezing
  • wheezing or a cough.

The main treatment for mould allergy, which is diagnosed by a skin prick test or an allergen- test, is to minimise exposure to mould. Other treatments include oral antihistamines, nasal sprays or immunotherapy to reduce sensitivity.

People with pre-existing respiratory problems can also be sensitive to mould. According to Asthma Australia, when a person with asthma inhales mould spores, they’re at increased risk of an asthma flare-up.

Those with other respiratory issues, and compromised immune systems, may also be negatively affected by mould.

1 in 4 homes contain mould

An estimated 26% of Australian homes have visible mould in areas other than the bathroom, according to a review of 9 studies published in the Medical Journal of Australia in 2018.

“Moulds can grow on almost any surface,” says Prof Douwes. “Homes affected by water damage or leaks, rising damp, condensation on walls due to poor insulation and ventilation, and high humidity, are very likely to be affected by indoor mould unless leaks or indoor dampness problems are remedied promptly.”

Indoor mould is often visible as a stain, smudge or discoloured patch on surface areas affected by condensation or leaks, but sometimes it's hidden within wall cavities. Other indications of damp problems may include a mouldy smell, water stains, condensation on the inside of windows, peeling or cracked paint, peeling wallpaper and puddles of water forming under or around the house.

Clearing your home of mould

The National Asthma Council Australia recommends taking the following steps to reduce your exposure to mould:

  • remove visible mould in your house by cleaning with naturally fermented white vinegar solution.
  • use high-efficiency air filters – these may be integrated in air-conditioning, ventilation systems or in stand-alone air purifiers.
  • ensure there is adequate natural ventilation in your home, including the use of extractor fans
  • seal leaks in bathrooms and roofs 
  • clear overflowing gutters and under-floor vents
  • remove indoor pot plants, as they promote mould growth
  • dry or remove wet carpets
  • treat rising damp as soon as it’s detected, by fixing leaks and installing a new damp-proof course at the base of the wall
  • avoid the use of organic mulches and compost heaps in the garden.

​​Mould isn’t always visible and some porous surfaces may need to be removed and discarded.

If your carpets have been affected, for example, these may need to be thrown away, depending on the level of contamination.

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