Final answer:
Asbestos is the banned cancer-causing substance that's sometimes found in ceiling tiles. It poses significant health risks when its fibers are released into the air and inhaled. Other carcinogenic substances like radon can also accumulate in buildings, posing health risks.
Step-by-step explanation:
A banned cancer-causing substance that's sometimes found in ceiling tiles is asbestos. Asbestos was used historically in building materials for its insulation properties and resistance to fire. However, when asbestos-containing materials break down over time or are disturbed, they can release fibers into the air that, when inhaled, pose significant health hazards such as lung cancer, asbestosis, and mesothelioma. This hazard is particularly acute in well-insulated, tightly sealed buildings where the accumulation of such fibers in the air is more likely.
In addition to asbestos, other substances, such as radon, also a carcinogen, can accumulate in buildings and pose similar risks. Radon is typically found in small amounts in soils and minerals but becomes a concern when it accumulates to high levels inside buildings. Measures to mitigate these risks include the proper management and removal of asbestos-containing materials and the ventilation or mitigation of radon in affected buildings.