Asbestos is a naturally occurring mineral that was commonly used in construction materials, such as insulation and roofing, due to its fire-resistant properties. However, once it became known that asbestos exposure can cause serious health problems, including mesothelioma, lung cancer, and asbestosis, asbestos use was banned in the UK in 1999. Despite this ban, many older buildings still contain asbestos materials. Asbestos only poses a risk when it becomes airborne and is inhaled, which is why it's important to have it removed by professionals.