The USS Silversides (SS-236) was one of the most successful submarines during World War II, having sunk 23 enemy vessels weighing a total of 91,444 tons. It received 12 battle stars, as well as a Presidential Unit Citation for cumulative action over four patrols. However, because it was built in 1940, asbestos may have been lurking in the wall insulation of the submarine, which put the health of those present on it at great risk. In 1969, the submarine was struck from the Naval Vessel Register and today, it can be found as a museum ship in Muskegon, Michigan.
Asbestos contains microscopic fibers that, when disturbed, enter the air and can be easily inhaled by anyone nearby. The durable nature of these fibers means they don't break down within the human body and they are impossible to expel - and instead become attached to the lining of the lungs, along with other areas of the respiratory system. It is these fibers that cause healthy cells to mutate and turn cancerous.