Asbestos is a proven human carcinogen,and all forms of asbestos can cause cancer.
The main way people are exposed to asbestos is by breathing in air that contains asbestos fibres.
Asbestos causes cancer in a dose-dependent manner. The greater the exposure, and the longer the time of exposure, the greater the risk of developing an asbestos-related disease.
No ‘safe’ lower limit of exposure has been identified with certainty - all exposure is thought to add to the overall risk of disease development - but the risk from a single, low-level exposure is considered to be extremely low.
Keep exposure to asbestos as low as possible.
Intact asbestos-containing material is not a risk merely by its presence. Potential health problems occur if asbestos fibres become airborne.
Diseases related to asbestos
Inhaling significant quantities of airborne asbestos causes:
- asbestosis (scarring of lung tissue)
- mesothelioma (malignant tumours, cancers that develop around the lungs or intestine)
- pleural plaques (thickening of membranes around the lungs)
- cancer of the lung, larynx and ovary.
Symptoms of asbestos-related diseases include breathing difficulties and ‘scarring’ of the lung that can be detected by x-ray.
Harmful effects following ingestion of asbestos have not been clearly documented. However it has been shown that few fibres are able to penetrate the gastrointestinal tract. Therefore the non-gastrointestinal effects from oral exposure to asbestos are unlikely. There is no consistent evidence that ingested asbestos is hazardous to health.
Smoking can increase the risk of developing lung cancer following exposure to asbestos.
The main way people are exposed to asbestos is by breathing in air that contains asbestos fibres. Small levels of asbestos fibres occur naturally in air, including as a result of weathering breaking down asbestos-containing materials, windblown soil from hazardous waste sites or deterioration of motor vehicle clutches and brakes.
The levels of asbestos in dust and windblown soil may be higher close to degrading asbestos cement clad buildings, or former sites of such buildings, or a waste site where asbestos is disturbed or not properly covered.
- Asbestos Exposure in New Zealand: Review of the Scientific Evidence of Non-occupational Risks – a 2015 report from the Royal Society of New Zealand and Sir Peter Gluckman
Based on our publication All about Asbestos: Protecting your health at home.