Asbestos is a natural mineral with versatile uses due to its heat resistance, tensile strength, and insulating and fireproof properties. In the past, it was woven into materials to be mixed with cement and widely used in numerous building products before being considered toxic. According to the Environmental Protection Agency (EPA), there are six different types of asbestos minerals, including chrysotile, amosite, crocidolite, tremolite, anthophyllite, and actinolite. Despite the different chemical compositions of the asbestos types, all commercial forms of asbestos are carcinogenic.
Evidence that asbestos could be toxic were discovered during the 1920s, and in the mid-20th century, investigators were able to establish the correlation between asbestos and severe respiratory diseases. Nowadays, asbestos is banned in over 50 countries and its use is limited in others such as the United States. However, since it was used in commercial and industrial construction for nearly 100 years, millions of workers had already been exposed to asbestos and 10,000 people continue to be exposed every year in the US alone.