What is Asbestos

Introduction

Asbestos has many valuable properties that make it commercially and industrially useful. This is why it is mined and used in many manufactured goods. In fact, asbestos fibres can be found in over three thousand different products and materials produced in contemporary times.1

Despite its practicality, asbestos is dangerous because each of the six types of the mineral is carcinogenic. This means when people are exposed to its fibres they have the potential to develop cancer.2 Asbestos can also cause non-malignant (non-cancerous) lung conditions such as asbestosis.

Defining ‘Asbestos’

The generic term ‘asbestos’ describes an array of fibrous minerals. These minerals have several characteristics in common: asbestos minerals are silicate minerals that form in veins of metamorphic or igneous rock over time.

The term ‘asbestos’ includes six kinds of minerals that are broken into two categories: serpentine and amphibole.

Chrysotile Asbestos

Chrysotile asbestos is the most commonly used type of asbestos. If a building in North America contains asbestos, there is a ninety-five percent chance it is chrysotile asbestos. This is because chrysotile asbestos was mined in Canada, mostly in Quebec. The last of the asbestos mines in Canada were closed in 2011.

Industry lobbyists have marketed chrysotile asbestos as a ‘safer’ alternative to amphibole asbestos. They argued that the health risks are low when chrysotile is handled with care, despite the classification by the World Health Organization of all kinds of asbestos as carcinogenic, including chrysotile. Recently, Health Canada has revised its statement that previously suggested that chrysotile is a less dangerous form of asbestos.2

Characteristics of Asbestos Fibres

Asbestos fibres have no smell or taste, and they are individually too small to see with the naked eye.1 Asbestos fibres cling to each other, creating a distinctive fibrous rock look.

While asbestos fibres may seem small and fragile, they are stronger than steel.The strength of asbestos combined with its durability, inflammability, flexibility, chemical inertness, solidity in water, and insular properties mean these fibres have many uses.4 This, as we now know, comes at a price of health.

How is Asbestos Mined and Processed?

There are asbestos deposits all over the world. Deposits are found throughout Canada, especially in the province of Quebec. Others are found in Russia, Zimbabwe, China, Brazil, Kazakhstan, and South Africa. Smaller deposits and mines are found in Australia, the United States, and Bolivia.5

Asbestos is mined from both open pit and underground mines. After being mined, it is separated from the rock by crushing it. A machine then segments the fibres by length.6 At the end of this process, most fibres are less than one centimeter long.

Once extraction is finished, the fibres are transported to a processing plant where the material can become a wide array of manufactured goods such as building materials, brake pads or fireproof cloth.

One of the challenges in advocating the ban of asbestos production, import, and export is that asbestos is a global resource and commodity. This is why it is essential that every country pushes for the ban of asbestos products. So far over 50 countries worldwide have banned the import and export of asbestos.

 

Resources

1. Barbalace, Roberta A. (2004). Asbestos, its Physical and Chemical Properties. Retrieved June 2013 from http://environmentalchemistry.com/yogi/environmental/asbestosproperties2004.html.

2. Health Canada (2015). Health Risks of Asbestos. Retrieved July 2015 from http://healthycanadians.gc.ca/healthy-living-vie-saine/environment-environnement/air/contaminants/asbestos-amiante-eng.php

3. WHO. (2006). Elimination of Asbestos-Related Disease. Retrieved June 2013 from http://whqlibdoc.who.int/hq/2006/WHO_SDE_OEH_06.03_eng.pdf.

4. United States Department of the Interior. (ND). Asbestos: Geology, Mineralogy, Mining, and Uses. Retrieved June 2013 from http://pubs.usgs.gov/of/2002/of02-149/of02-149.pdf.

5. The Mesothelioma Knowledge Center. (2013). Asbestos Mining & Milling. Retrieved June 2013 from http://www.mesothelioma.com/asbestos/what-is-asbestos/asbestos-production.aspx.

6. How Stuff Works. (2013). Asbestos. Retrieved June 2013 from http://science.howstuffworks.com/environmental/earth/geology/asbestos-info.htm.