Energy Consumption and Air Pollution Transportation requires huge amounts of energy. This energy consumption contributes to both local and global air pollution and presents an economic burden, especially in countries that import energy resources. In the cities of the developed world, car emissions pose the greatest threat to air quality. In the developing world, automotive air pollution is mostly a problem in large cities with high levels of traffic, such as Mexico City, Bangkok, and Lagos, Nigeria. In other cities, power plants, factories, and other stationary sources still constitute the greatest threat to air quality.
Motor vehicles are also a significant factor in lead emissions.
An estimated 80 to 90 percent of lead in ambient air is d erived from the combustion of leaded gasoline . Recognizing the health threat, most developed countries have reduced the lead content of gasoline over the past decade. The impacts of motor vehicle emissions extend far beyond the local area. These problems exist in cities in both the developed and the developing world, although the causes and symptoms are somewhat different. In the United States, suburban flight has left the urban poor concentrated in city centers far from jobs, stores, and entertainment services that have relocated to the periphery as well.