Automobile

Environmental impact
Transportation is a major contributor to air pollution in most industrialised nations. According to the American Surface Transportation Policy Project nearly half of all Americans are breathing unhealthy air. Their study showed air quality in dozens of metropolitan areas has worsened over the last decade. In the United States the average passenger car emits 11,450 pounds (5,190 kg) of carbon dioxide annually, along with smaller amounts of carbon monoxide, hydrocarbons, and nitrogen.
Animals and plants are often negatively impacted by automobiles via habitat destruction and pollution. Over the lifetime of the average automobile the "loss of habitat potential" may be over 50,000 square meters (540,000 sq ft) based on primary production correlations.