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Moulds are a fungus that grows on food or materials in homes or other buildings. Mould can grow in wet or damp areas, including ceiling tiles, carpets, wallpaper, insulation material, wood, and drywall. 

The most common health problems associated with exposure to mould are: 

  • Eye, nose and throat irritation 
  • Runny nose, sinus congestion, frequent cold symptoms 
  • Wheezing or shortness of breath  
  • Worsening of asthma symptoms 

Anyone experiencing any of these symptoms should consult a physician. 

Who is at risk? 

Moulds can release spores and various chemicals into the air when they grow. When left to grow indoors, some people may experience allergic reactions or and asthma attacks. Anyone can be affected by moulds, but some people are more susceptible than others including: 

  • People with asthma or allergies to moulds 
  • Infants and young children, whose lungs are still developing 
  • People with weakened immune systems 

The best way to prevent the growth of indoor mould is to make sure mould spores do not have the food and moisture that will permit their growth: 

  • Clean your bathrooms regularly and keep them dry by using your bathroom fan when showering or bathing. 
  • Use the kitchen fan to limit the moisture created in your home through cooking. 
  • Fix water leaks and condensation problems as soon as possible. Windows that have condensation problems in the winter should be cleaned regularly.  
  • Dry any water damaged building materials or furnishings within 48 hours. If something cannot be dried quickly it should be discarded.

If you are a tenant, all the precautions above apply to you also. If there is a problem you cannot resolve on your own, advise your landlord as soon as possible, and if the landlord has not taken action to resolve a mould problem in a reasonable amount of time contact the Landlord Tenant Board and report the problem to your local municipal Bylaw department. 

Health Canada suggests seeking professional cleaning assistance if you have: 

  • an area of mould greater than a square meter, or 
  • more than three patches of mould each less than a square metre in area. 

When cleaning up mould impacted areas on your own, consider the following: 

  • Think of your personal safety when cleaning up mould: Wear protective clothing such as rubber gloves, eye protection and a mask when cleaning up mould. A disposable respirator, such as an N95 mask, should fit well to your face covering your nose and mouth to protect against mould and dust in the air while cleaning and follow the manufacturer’s instructions for proper use. 
  • Use soap and water to clean mould on hard surfaces: Clean with soap and water and rinse with clean water. Bleach is not necessary to clean up mould that is not related to a flooding event. Learn more about flood cleanup. 
  • Discard absorbent or porous materials that cannot be washed and dried. Materials such as ceiling tiles, upholstery and carpet may need to be thrown away if they become mouldy, as they can be very difficult to clean. 

The following agencies can provide information on indoor moulds, their health effects, proper mould clean-up procedures, and advice on health problems related to indoor air quality 

  • Haliburton, Kawartha, Pine Ridge District Health Unit
    1-866-888-4577 x 5006  

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