BOB KNUCKEY writes about the health hazards of mould …
Mould is just one form of fungi that comprises around one quarter of the biomass of the planet and are the most frequently occurring airborne micro-organisms in both indoor and outdoor environments.
Mould is actually used in many beneficial ways including in bread making, brewing and making medicines and drugs. Mould is necessary for the earth to function, cleaning up our rubbish and waste. Yet it can also cause significant damage to buildings, such as the structural decay of timber as well as creating health problems for us.
Normally, our everyday exposure to airborne mould in the outdoor air presents little or no risk to our health. However, the airborne mould in the artificial environments of our buildings and dwellings have an altered composition, which can create an environment (often called sick building syndrome or SBS) with the potential to greatly affect human health.
The health effects of mould exposure
Human exposure to airborne mould spores can result in a variety of adverse health effects. Reactions to exposure include:
- Allergic and irritant responses
- Infectious disease such as histoplasmosis, blastomycosis, and aspergillosis
- A variety of respiratory diseases including asthma, allergic rhinitis, hypersensitivity pneumonitis and bronchial hyperactivity
- Acute toxicoses
- SBS symptoms
- Cancer from exposure to mycotoxins
- Immune suppression
- Pulmonary oedema and even death
Fungal allergens have been identified as the major allergen source associated with the development of childhood asthma. However it should be noted that exposure to fungi does not always cause allergy, as allergy only develops in a sensitised individual.
There is also persuasive evidence that exposure to fungi at work is responsible for many cases of illness. Mycotoxins, unlike fungal allergens, cause a wide range of chronic systemic effects in humans and will elicit toxic responses from virtually all individuals who are exposed. Exposure to mycotoxins in the indoor air is almost exclusively through either inhalation of spores containing the toxins or gaseous forms released during metabolism. These toxins attach the bronchial and lung tissues, which are particularly sensitive to chemical assault, and the mucosa lining exhibits strong responses to fungal immune-active agents.
Unpleasant odours, such as the characteristic mouldy smell in damp basements is the result of vapour pressure known as a Volatile Organic Compound (VOC). The vapour pressure (off-gassing) from plants including mould is biological. Man-made VOCs are found in materials containing formaldehyde, especially paints, coatings and solvents, as well as cleaning products and refrigerants based on fossil fuels etc. Whilst VOCs are typically not acutely toxic, exposure to fungi and it’s off-gassing in contaminated buildings can have the same chronic effects such as headaches, dizziness, and eye and mucous membrane irritation.
What are the symptoms?
- Respiratory problems wheezing, asthma, emphysema, difficulty in breathing, shortness of breath.
- Central nervous system problems constant headaches, memory problems, inability to concentrate, mood changes
- Nasal and sinus irritation leading to frequent colds, sinus headaches
Nose and throat irritation, runny nose, dry hacking cough, sneezing - Watery and red eyes
- Skin irritation (dermatitis)
- Unexplained aches and pains
- Nausea/Diarrhoea
- Chronic fatigue
- Fever
Who should be concerned?
- Exposure to fungal spores has been identified as having statistically significant risk factors for respiratory health in children. The fungal material is often small enough to penetrate deep into the lungs when inhaled.
- Occupants of any building with a history of mouldy smells, dampness or lack of sunlight and ventilation.
- Mould Remediation Workers in a building that has been subject to water ingress for a period of time particularly Grade 5 Buildings where there is little obvious evidence of mould damage. If any of the symptoms listed appear to be related to time spent in the building then they should be duly noted and recorded.
Research
Epidemiological studies and reviews of the literature have found an emerging relationship between ‘home-dampness’ and respiratory symptoms and allergies, particularly in children. However, little is known about the underlying mechanisms for these associations.
In the UK a study of 16.8 million houses estimated that 18% of houses (2.8 million) had mould growth or damage to decorations and furnishings caused by dampness. Humid air-conditioned buildings with design, operation and maintenance problems are also often contaminated with fungal growth.
The Australian Institute of Architects has reported that up to 40% of Australian houses have dampness problems. Fungal problems associated with occupant complaints are also well known and documented and are often cited as contributing to sick building syndrome (SBS) complaints.
What can we do to protect our health for the adverse effects of mould?
First of all, we should make one thing clear, you haven’t got this problem because your home is dirty. We’ve found that two of the prime causes of mould growth and musty smells is lack of ventilation and insufficient sunlight.
Two sure fire ways of fixing your problem for good are:
- Remove your entire roof and allow sunshine to stream in, and
- Remove all your walls and allow your home to be FULLY ventilated
Of course both these methods are impractical and impossible, but hey!, you can pull back curtains and blinds and open windows and doors to allow as much sunshine and fresh air into your home as possible.
Sometimes though it’s impossible to achieve good ventilation and air flow or to get sunshine and light into all rooms of your home.
The surest means of maintaining correct humidity levels and good air quality in your home is to have a suitable domestic dehumidifier. This is a free standing appliance which literally removes moisture from the air and can be set at a pre-determined humidity level to operate only when necessary.
In this way you will also be protecting your furniture and fittings (bedding, curtains, lounges etc) as well as household items like books, cupboards, electronic equipment etc. and anywhere else that moisture tends to settle.
If there is mould growth in your home, you must clean off the mould and fix the moisture source problem. If you clean up the mould, but don’t fix the moisture problem then, most likely, the mould problem will recur.
If mould is present, spores will be found floating through the air and in house dust. Do not brush off visible mould. Wipe with a damp cloth. Diluted vinegar is a effective natural cleaner which will also help to kill the mould spores. Another excellent cleaner is Aqua Magic a truly ‘green’ environmentally responsible multi-purpose cleaner.
Mould spores will not proliferate readily if moisture is not present. Indoor mould growth is not natural and should be prevented.
To improve the air quality in and around your home, seek further information about Dehumidifiers, Sub-floor ventilators and Roof ventilators check out www.moisturecure.com.au
