Naturally occurring asbestos FAQs
Frequently asked questions to help assist people involved in day-to-day operations on land that does, or may contain, naturally occurring asbestos (NOA) - such as farmers, other property owners, property managers and gardeners.
Key points
- Less than 1% of the land surface of NSW is estimated to have the potential for NOA within 10 metres of the land surface.
- Asbestos occurs in some rocks and soils as a natural mineral.
- Asbestos is not considered dangerous when it is left undisturbed.
- When asbestos is disturbed or worked with, asbestos fibres can be released into the air.
- Breathing in asbestos fibres can increase the risk to your health but does not necessarily mean you will develop health problems.
- The risk of developing an asbestos-related disease depends on how many fibres have been breathed in and for how long, type of fibre, whether you smoke and age at first exposure.
- It is prudent to take simple precautions where practical to minimise potential exposure.
- The maps identify potential locations of naturally occurring asbestos - they do not identify all places where it actually exists.
What is NOA and how does it form?
Asbestos is a name given to group of naturally occurring fibrous silicate minerals found in rock, sediment, or soil, and the term NOA distinguishes these natural occurrences from manufactured products that contain asbestos. Asbestos minerals are commonly found around the world in certain types of rock including serpentinite (chrysotile [white]) and amphibole (actinolite, amosite [brown], anthophyllite, crocidolite [blue] and tremolite) as well as in the soils formed from these rock types.
Depending on the probability of naturally occurring asbestos being present, NSW has been mapped into low, medium, or high potential regions. The map is only indicative and based on knowledge at the time of writing. Only testing will confirm if NOA is present onsite.
These NOA factsheets contain further information:
- Recreation in areas of naturally occurring asbestos
- Residing in areas of naturally occurring asbestos
- Farming in areas of naturally occurring asbestos
Where is NOA typically found, and how can I recognise landscapes where NOA might occur?
In NSW there are three main areas known to have NOA:
- The Great Serpentinite Belt (near Barraba)
- The Gordonbrook Serpentinite Belt (near Baryulgil)
- The Coolac Serpentinite Belt (near Gundagai).
Minor quantities of asbestos have also been found in metamorphosed mafic rocks and limestone near Orange, Rockley (Bathurst Regional Council), Newbridge (Blayney Shire Council), Wellington and Broken Hill.
The only certain way to identify whether NOA is present on your property is to have on-site testing conducted. Testing can be performed by independent service providers , the Australian Institute of Occupational Hygienists (AIOH) website, or by searching for asbestos consultants in directory services. Ideally, test laboratories should be accredited by the National Association of Testing Authorities (NATA).
One indication of areas with NOA is that they may have flora lacking in numbers or variety, with the plant species present showing inhibited or stunted growth [1] - Agricultural crops and grazing pastures may be similarly affected. Soils that form from the rock-types typically associated with NOA tend to have low fertility and a mineral composition that can harm plant growth.
What does NOA look like?
NOA varies in appearance, ranging in colour from green, grey to yellow or white. It may not be easily recognised and testing is required to confirm its presence.
Figure 1. Naturally occurring asbestos outcrops and rocks confirmed
Who can I contact to determine if I have NOA on my property?
If in doubt, or if you have any concerns, it may be prudent to verify, through on-site testing whether NOA is present. Testing can be performed by independent service providers who can be found at the SafeWork NSW website, Australian Institute of Occupational Hygienists (AIOH) website, or by searching for asbestos consultants in directory services. Ideally, test laboratories should be accredited by the National Association of Testing Authorities (NATA).
Alternatively, take a precautionary approach and assume there is NOA on the property if it falls within an area on the map with a medium or high probability of NOA being present and manage the property as suggested below and in the accompanying NOA fact sheets.
Can I disturb rocks and soil I identify as NOA on my property by myself?
The recommended action is to minimise disturbance of NOA material. In most circumstances leaving the material in place and covering with soil or other material that is known to be free of NOA is an effective control.
If NOA is to be disturbed, it’s important to take precautions as identified in the supporting fact sheets:
- Recreation in areas of naturally occurring asbestos
- Residing in areas of naturally occurring asbestos
- Farming in areas of naturally occurring asbestos
Persons conducting businesses or undertakings (PCBUs) will have requirements for an asbestos management plan under the Work Health and Safety Act 2011. People who are not conducting a business or undertaking who propose to disturb NOA on their property should consider developing an asbestos management plan.
Health
What is the risk of developing an asbestos-related disease?
Asbestos is not a risk if it is undisturbed as only asbestos fibres that are breathed in pose a risk to health. People living in a NOA area will have a slight risk of asbestos-related disease and this risk may be greater than for people not living in a NOA area. The risk of developing an asbestos-related disease varies from person to person and depends on how many fibres have been breathed in and for how long, fibre type, whether you smoke and age at first exposure.
We are all exposed to very low levels of asbestos in the air we breathe. There are usually between 10 and 200 asbestos fibres in every 1000 litres of air. This means we breathe in up to 3000 asbestos fibres a day [2]]. Despite this very few people experience ill effects from such exposure.
People can also be exposed to higher levels of asbestos at some times in their lives; for example in their workplace, community or home. Evidence of non-occupational exposure increasing risk of asbestos-related disease is very limited. A small increase in risk cannot be excluded, but a large increase in risk is unlikely.
Most people who develop asbestos-related diseases in Australia have had exposure to much higher levels of asbestos fibres through working directly with asbestos or asbestos products. Family members of these workers have also been known to develop asbestos-related diseases because the workers carried asbestos fibres home on their clothing, skin and hair.
While there is only a low chance of developing an asbestos-related disease from non-occupational exposure to asbestos, it remains very important to take precautions to minimise exposure. Practical steps for minimising exposure can be found in the factsheets.
What are asbestos-related conditions?
When asbestos fibres are inhaled deep into the lungs, they can cause inflammation and scarring, which can lead to a number of asbestos-related conditions. The four main asbestos-related conditions are pleural plaques, asbestosis, lung cancer and mesothelioma:
- Pleural plaques are areas of white, smooth, raised scar tissue on the outer lining of the lung, internal chest wall and diaphragm. Pleural plaques are uncommon, and their occurrence is usually associated with exposure to asbestos. Most people with pleural plaques have no symptoms.
- Asbestosis is a chronic lung disease caused by inflammation or scarring in the lungs. It is associated with asbestos exposure and causes breathlessness, coughing, and permanent lung damage.
- Lung cancer is a tumour that develops in the lungs. People who are exposed to asbestos and smoke or have pre-existing lung disease have a higher chance of developing lung cancer.
- Mesothelioma is a cancer of the tissue that lines the body cavities, particularly the chest and abdominal cavities. It is almost exclusively caused by exposure to asbestos and usually takes a very long time to develop.
How long does it take to develop asbestos-related diseases?
Asbestos-related diseases can take a long time to develop. Asbestosis can take 10 to 20 years to develop after initial exposure, whereas mesothelioma may take 30 to 45 years to develop.
Is there a screening test for asbestos-related diseases?
There are currently no screening tests that have been shown to confidently identify early stages of asbestos-related diseases.
Veterinary and agricultural considerations
If I think I have large clumps of NOA on my grazing land and I cover it with vegetation, will the plant roots absorb the asbestos and affect livestock or native animals if they eat it?
No.
Can heavy rain or hail stones cause NOA to splinter and be released into the air?
It is unlikely that rain or hailstones will generate elevated levels of airborne fibres. Water is often used as a suppression agent to reduce potential to liberate fibres.
However, in badly eroding landscapes, heavy rainfall may move surface soil containing NOA onto new areas where it may be disturbed subsequently by human activity or wind. Therefore actively eroding areas should be stabilised, and advice about how to do this is available from the Department of Primary Industries, Local Land Services or search for private consultants. Wind can cause dust to become airborne.
What happens if rain carries affected soil to another part of my property where I grow crops or fruit trees? Will the roots of the crops and fruit tress absorb the NOA and make them inedible?
There is no evidence that asbestos can be taken up by plants and incorporated into the foliage or fruit, although root vegetables should always be carefully washed to remove soil. There should be no adverse impact from NOA itself upon the crops or their suitability for consumption.www.dpi.nsw.gov.au/agriculture/resources/soils/erosion/soil-erosion-
However, the serpentine soils typically associated with NOA may also contain heavy metals such as chromium, cobalt and nickel which, depending on the bioavailability of the particular chemical composition that is present, might be taken up by plants.
If the NOA run-off ends up in a dam on my property and animals drink the water, are they safe?
Asbestos fibres can pose a risk to the health of humans and other mammals if airborne, as inhalation is the main way that asbestos enters the body. Water will suppress the generation of dust.
The World Health Organisation has stated that concentrations of asbestos in drinking water from asbestos cement pipes do not present a hazard to human health [3].
Would I be better fencing off above-NOA deposits?
Avoid activities that will generate dust from areas of NOA. Fencing to exclude unnecessary access to, and disturbance of, NOA areas is one option for minimising potential for dust. Other measures include covering the area with soil or other materials that are free from NOA.
In undertaking any fencing activities, it’s important to minimise the disturbance of NOA.
I have a vast property. How can I be expected to check every square metre for NOA?
It is not necessary to survey every square metre of your property. If you have reason to believe your property is in an area of high potential for presence of NOA, manage your activities to minimise the generation of dust, and only carry out dusty activities where you know it is free of NOA.
Landowners
How can I possibly know whether NOA is underground on my property, especially if it’s in the 1% of NSW that has NOA?
NOA is only a potential risk if it is accessible and subjected to considerable disturbance that would generate elevated levels of airborne dust. A map showing these areas can be seen here. The map is only indicative and based on knowledge at the time of writing. Only testing will confirm if NOA is present onsite.
The supporting NOA factsheets contain further information and links:
- Recreation in areas of naturally occurring asbestos
- Residing in areas of naturally occurring asbestos
- Farming in areas of naturally occurring asbestos
Is there a scientific process available that enables the deep underground to be photographed, X-rayed or have small core samples taken to detect NOA without disturbing it?
We are unaware of existing technologies that would identify NOA underground without disturbing the soil/rock.
If NOA is discovered on my property and I want a more permanent solution than simply covering it with vegetation, how can I get it removed?
It is unlikely to be practical to remove the NOA, and strict controls would need to be put in place throughout the whole operation of removal.
However, covering the NOA with clean soil (or other material) that does not contain NOA is recommended as a satisfactory and effective solution. Where covering is not practicable, a NOA area should be managed in a way that minimises the generation of dust.
Do I have to pay for the removal of NOA? If so, is there a government or council subsidy?
It is not likely to be practical to remove NOA. Farm management practices should seek to minimise its disturbance and/or generation of dust in NOA areas.
Will NOA reduce the value of my property and make it harder to sell?
The presence of NOA is one of many natural attributes that determines that productivity and value of any land.
General
Where do I go for more advice?
- SafeWork NSW (13 10 50) for asbestos in the work environment
- NSW Health (1300 066 055) for health enquiries
- NSW Environment Protection Authority (131 555) for disposal enquiries
What can a council do if it confirms an occurrence of NOA not on the map?
Local councils who confirm the presence of naturally occurring asbestos on land that is not identified on the mapping can provide the information to the Geological Survey of NSW. The information must be in the form of a report prepared by a qualified person that identifies the type of asbestos and its confirmed location. The information can be sent to the Geological Survey of NSW at minsys.info@trade.nsw.gov.au
Footnotes
[2] enHealth (2012) Asbestos – A guide for householders and the general public