Asbestos & asbestos-related diseases


Asbestos refers to a group of six fibrous, microscopic, silicate minerals. Due to their durability and fire resistance, they were used in a number of commercial and industrial capacities, including roofing, flooring, cement, and textiles. It was discovered in the 1970s that asbestos was a threat to human health, as research showed all types of asbestos to be carcinogenic.1 Inhalation of asbestos fibres may cause a kind of malignant cancer called mesothelioma, which can lead to larynx, ovary, and lung cancer. An individual is especially at risk if their lungs are already damaged due to smoking. In addition to mesothelioma, inhalation of asbestos can cause asbestosis, a kind of pneumoconiosis, a restrictive and chronic lung disease.2


Asbestosis is the result of scarring caused by asbestos fibres becoming trapped in a person’s lungs. Once in the lungs, the fibres cause inflammation, resulting in the buildup of scar tissue over time. This inhibits a person’s ability to breathe properly. For this reason the main symptom of asbestosis is breathlessness.

Asbestosis can make a person’s lungs more vulnerable to lung cancer and mesothelioma, especially if the individual is a smoker and has inhaled a large cumulative amount of asbestos.

Like all other asbestos-related diseases, asbestosis occurs after a long latency period, meaning it can take many years for the disease to develop after initial exposure.


Mesothelioma is a rare cancer that is almost always caused by exposure to asbestos. It may appear in the lining around many of the body’s internal organs, including abdomen and around the heart. but is most commonly found in the lungs. Symptoms include coughing, fatigue, shortness of breath, and a feeling of heaviness in the chest due to fluid buildup in the lungs.3

Unfortunately, there is no current cure for mesothelioma. By the time it is detected, most individuals diagnosed are expected to have only about a year to live. Nevertheless, new research and treatments for the disease are helping in extending life expectancy.

In 2010, 515 Canadians were diagnosed with mesothelioma4.

For more information, visit our mesothelioma page.

Latency Period

Asbestos-related diseases have a long latency period. A person can be exposed to asbestos between 10-50 years before they develop mesothelioma, lung cancer, or asbestosis.5 The median latency period is about 30 years, and disease very rarely occurs before 15 years.6

The latency period can be affected by the degree of asbestos exposure, which varies based on the concentration of asbestos fibres in the air, the length of exposure, and the number of times a person is exposed.

Because asbestos related diseases have such a long latency period, civil procedures can be difficult to prosecute because of rules around statute of limitations. Some countries, like Australia, have adjusted their statute of limitations regarding workplace legal issues to remove this barrier in order to better prosecute companies and corporations who knowingly put their workers in danger of asbestos related diseases.7



1. World Health Organization. (2006). Elimination of Asbestos-Related Diseases. Retrieved June 2013 from

2. Health Canada (2015). Health Risks of Asbestos. Retrieved July 2015 from

3. Mesothelioma Resource Online. (2013). Early Symptoms of Mesothelioma. Retrieved June 2013 from

4. Canadian Cancer Society’s Advisory Committee on Cancer Statistics. (2015). Canadian Cancer Statistics 2015. Toronto, ON: Canadian Cancer Society.

5. The Mesothelioma Center. (2013). Mesothelioma Symptoms. Retrieved June 2013 from

6. Lanphear, B. P. & C. R. Buncher. (1992). Latent period for malignant mesothelioma of occupational origin. Journal of Occupational Medicine, 34(7), 718 – 721.

7. Australian Asbestos Network. (2013). The Battles in Australia. Retrieved June 2013 from