Asbestos is a mineral used for fireproofing and insulation. It occurs naturally in metamorphic rocks near subduction zones from the mineral serpentine. Asbestos is only dangerous when the fibers are airborne, so caution must be taken when renovating older facilities, drilling in walls, or accessing suspended ceilings, as asbestos may have been used in the insulation. Asbestos can cause various lung diseases including cancer and internal scarring, which impairs lung function.
Here is a list of some products that may contain asbestos.