Are there health effects?

Current scientific and medical evidence supports the fact that simply living or working in a building containing asbestos is not dangerous as long as the asbestos is in good condition (i.e. undamaged).

It is when asbestos is worked with or disturbed and asbestos fibres are released that the risk of developing an asbestos related disease is increased.

The people at greatest risk of developing an asbestos related disease are those that frequently undertake repairs, renovations and other work which can generate the release of asbestos fibres into the air.

However, asbestos is only a risk to health when asbestos fibres become airborne and are inhaled into the lungs. Most fibres are removed from your lungs by your body's natural defences (e.g. coughing); however some fibres can remain in the lungs.

The risk to health increases with the number of fibres inhaled and with frequency of exposure. Asbestos-related diseases usually take many years to develop. The risk of developing an asbestos-related disease increases in proportion to the number of asbestos fibres breathed in over a lifetime. Occasional exposures to low concentrations of asbestos fibres, for example from house fires or renovation work on a neighbouring property, are likely to be associated with low risk to health.

The idea that 'one fibre will kill' is not supported by scientific evidence as everyone has had some exposure to asbestos fibres. The burden of asbestos fibres in the lungs, resulting from typical background exposure, appears to be tolerated by most people. Post-mortem studies of people aged between 60 -79 years who had not died from asbestos-related diseases have shown up to one million asbestos fibres per gram of dry lung tissue.

Except in cases of high occupational exposure, the incidence of asbestos-related disease is usually low.

Breathing in asbestos fibres has been linked to three asbestos related diseases, all of which can be fatal. Asbestos-related diseases take time to develop. They usually emerge at least 10 years after exposure, and sometimes as long as 50 years later. Currently there are no cures for these diseases.

Asbestosis

A chronic lung disease that can lead to respiratory impairment and to diseases such as lung cancer. Asbestosis causes widespread interstitial fibrosis (scar tissue between the alveoli, spread over the lung).

It is difficult to distinguish from other causes of interstitial fibrosis and only confirmation of exposure to asbestos or detection of unusually high numbers of asbestos fibres in the lung is considered conclusive evidence of this disease.

Mesothelioma

A cancer of the lining of the pleura (outer lung lining) or of the peritoneum (the lining of the abdominal cavity).

• It is a rare disease - incidence is 1 in every 100,000 for males and 0.3 in every 100,000 for females.
• Asbestos is not the only cause of this disease, but it is the most important cause in modern times.
• Crocidolite is the most important asbestos-related factor, but amosite, chrysotile and tremolite are also linked.
• This disease takes 20-50 years to appear, with the highest risk around 30-35 years after exposure.
• It is typically dose-related, but in rare cases has been known to occur in patients with little known occupational exposure to asbestos.

Lung cancer

Cannot be distinguished from those cancers that are caused by other agents such as tobacco smoke.

• Lung cancer is relatively common among the general public and is the cancer most frequently associated with asbestos.
• Tumours grow and eventually obstruct airways.
• No characteristics specify a lung cancer as being caused by asbestos - we cannot distinguish a cigarette lung cancer from an asbestos lung cancer or another lung cancer.
• Smoking multiplies by 10 the risk of death due to lung cancer for asbestos workers.

More asbestos health information

Dr Keith Adam, a specialist in occupational medicine for over 20 years, and Education Queensland have developed a series of short asbestos 'vodcasts' designed to provide viewers with factual information about asbestos-related illness.  These vodcasts have been made available by WHSQ through a partnership with the Department of Education, Training, and Employment. 

• What is asbestos: the types of asbestos, its attributes and its uses (run time 2min 23s)
• What are the health effects? the types of health effects that can result from asbestos exposure. (run time 6min 28s) (note – legislation now prohibits the use of all asbestos)
• What can we do following exposure: the health monitoring methods, and limitations of such, used to detect asbestos related diseases (run time 3min 30s)