Asbestos

Asbestos is a group of six naturally occurring minerals made up of heat-resistant fibers. It was used in thousands of U.S. consumer products before the dangers of asbestos were known. Asbestos causes mesothelioma, lung cancer and other cancers. Asbestos is regulated in the U.S., but not banned.

https://www.epa.gov/asbestos/learn-about-asbestos