Answer:
Air pollution
Step-by-step explanation:
Rapid industrial and city growth brought about great problems in the urban settlement, as there were various dangers to safety and health. Those industrial cities that rapidly expanded were subject to contaminated air and water, and communicable disease at that time was rampant. However poor sanitation led to huge deaths during this period. In the 19th century however, the health condition was improved as a result of better sanitation.