Asbestos refers to six minerals that occur naturally as hardy, heat-resistant fibers. Long-term exposure to asbestos through inhalation or ingestion can lead to serious health issues like mesothelioma, asbestosis, and lung cancer. Precautions like proper ventilation and protective equipment can reduce the risks of asbestos exposure for those working with asbestos-containing materials. Asbestos was commonly used in construction and insulation but its use has declined due to health concerns.