vehicles, 200,000 trucks and 15,000 buses that take up space on the city’s roads and highways on a daily basis (Plá). Vehicle use creates many different gas emissions that are harmful to the environment, including carbon dioxide, carbon monoxide, nitrogen dioxide, and particles including lead and other heavy metals that can be extremely harmful not only to the environment, but to human health as well. In 2000, the total number of registered vehicles in Argentina reached 4,785,189, and this number has only increased since then, magnifying the amount of pollutants released into the air daily and exacerbating the environmental consequences of their use (Plá). The large-scale release of particulate matter and polluting greenhouse gases by thermal energy plants constructed to support the energy needs of the sprawling Argentine metropolises exaggerates the effects of air pollution caused by vehicles that the cities of Argentina have experienced. In Buenos Aires, the fourteen stacks of three major power plants located on the northeastern edge of the city burn natural gas about 350 days out of each year, but must burn gas-oil during the approximately 15 coldest days of the year to produce power; this combination of use of natural gas and gas-oil sources is one the major cause of air pollution in the city (Reich). Based on data collected in 2006, it was estimated that power plants in Buenos Aires release approximately 105 tons of

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