MOULD

Mould is a common component of household and workplace dust; however, if present in a large amount, it can present a health hazard to humans, potentially causing allergic reactions and respiratory problems. Some moulds also produce mycotoxins that can pose serious health risks to humans and animals. Some studies claim that exposure to high levels of mycotoxins can lead to neurological problems and, in some cases, death. Prolonged exposure, e.g. daily home exposure, may be particularly harmful.

Health Effects Include:
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Allergies, Aggravation of respiratory problems, Eye and skin irritation, Headaches and nausea, Flu-like symptoms. Those with pre-existing asthma and those with weakened immune systems, as well as infants and the elderly are at the greatest risk.

How to Spot Mould:
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If mould is present in a form that is likely to cause health effects, it will usually be very visible. However, stachybotrys and other toxic moulds often grow only inside wall cavities.
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When mould is contained in a sealed environment, it is not a threat to the home’s occupants. However, if mould spreads to walls and floors and becomes visible, or if wall cavities are opened, the spores can be released.

Formal identification of harmful moulds, such as Stachybotrys chartarum (known as ‘black mould’) can only be carried out at laboratories. It's a greenish-black mould that grows on material with high cellulose content, such as fibreboard, that has become extremely wet and has remained wet for some time. Excessive indoor humidity resulting in condensation on the walls will further promote its growth.
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Clean-up Procedures
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Spores are more easily released when mouldy materials dry out, so it is important to clean up any mouldy areas while they are still wet.

You should wear protective clothing that is easily cleaned or discarded, rubber gloves and a face mask (ask for a respirator with P1 particulate filters at a hardware store).
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The Ministry of Health and BRANZ recommend cleaning away any mould with commercial mould cleaner or hypochlorite bleach as soon as it appears on internal surfaces. Apply 1½ cups of household bleach to 4 litres of water and leave for 10 minutes before rinsing and drying.

Any affected materials that are removed should be wrapped in plastic before being disposed of. In extreme cases, porous materials such as carpets and curtains may be difficult to thoroughly clean and may have to be thrown out. Your local council will be able to advise you on this.

If there are extensive areas of mould and dampness in your home or if you have allergic reactions, it may be best to seek experienced advice on its removal, including whether to employ a professional cleaner.

Prevention

Better ventilation, more heating and higher levels of insulation can prevent the growth of moulds. Simple measures such as using an extractor fan in the bathroom and kitchen are effective forms of ventilation. Heating and insulation increase the capacity of the air to hold moisture and prevent high humidity. Mould can NOT grow without high humidity or condensation.

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