t systems, the United States has made great strides in maximizing environmental and health gains in this area.When gasoline molecules in a car’s engine do not burn completely, hydrocarbon emissions occur. The hydrocarbons react with nitrogen oxides and sunlight to form ground-level ozone, a major component of smog. This smog irritates the eyes, damages the lungs, and aggravates respiratory problems. A number of exhaust hydrocarbons are also toxic, with the potential to cause cancer. To combat this, fundamental improvements in engine design have been made, charcoal canisters have been added to collect these hydrocarbon vapors, and exhaust recirculation valves have been installed to reduce the nitrogen oxides. Research is ongoing for a gasoline that will burn more efficiently and have less evaporative hydrocarbon emissions as well; thus reducing the amount of hydrocarbons discharged to the catalytic converters. Sulfur and phosphorous are also severely restricted in gasoline production by the Environmental Protection Agency (EPA) because of their adverse affects on exhaust catalysts and their corrosive properties. Sulfur may also be emitted as polluting sulfur oxides, which damage lungs and contribute to the formation of acid rain. The personal automobile is still considered to be the single greatest air polluter in the world today, but provisions of the 1990 Clean Air Act are continuously and systematically reducing vehicle emissions. The petroleum industry and automobile manufacturers are being mandated to “clean up their acts” and the world will hopefully be a healthier, less polluted place to live in the future for all of this! We aren’t burning kerosene or lead in our automobiles any more, but we still have not found the ideal combustible fuel that we need. Emission control systems are becoming increasingly effective and thorough at what they do. This is just a stopgap solution and not the final ans...
