When did people find out that asbestos caused mesothelioma?

Romans knew thousands of years ago that slaves working in asbestos mines died at an unusually young age, but it wasn't until early in the 20th century that specific asbestos-related health effects were identified, and it was later still before the mineral was regulated in the United States. Though many countries have banned asbestos use due to health concerns, it is still in use in the U.S. Asbestos is fire-resistant, strong and flexible insulator, making it a useful material for construction.