Asbestos is a naturally occurring mineral that was widely used in construction materials during the 20th century. It was prized for its durability, fire resistance, and insulating properties. However, it was eventually discovered that exposure to asbestos fibers can cause serious health problems, including cancer and respiratory illnesses.

As a result, the use of asbestos in construction materials was phased out in the 1980s and banned entirely in the UK in 1999. However, many buildings that were constructed before these regulations came into effect still contain asbestos.