12. New York, NY
Major Causes of Pollution: 3 (High Population Density, Toxic Waste from Factories, Oil Spill)
New York is one of the most populated cities in the country, and the population density is extremely high. The good news is that due to the transportation system in New York air pollution remains relatively low. The rivers and waters in the city are also well maintained. However, there are places in New York that are filled with toxic sludge, and the Greenpoint Oil Spill of the past have contaminated the city’s groundwater.
