Old commercials for Fram oil filters used to end with a mechanic delivering the tag line “you can pay me now or you can pay me later” — implying that a small payment today would avoid a large payment later. The Gulf oil disaster has made plain that the "price" of oil is higher than just what consumers pay at the pump. Our national dependence on oil has multiple external costs — in addition to the risks of oil spills from tankers or exploded offshore drilling rigs. Among the largest and most significant are the health impacts associated with refining and burning petroleum fuels, in particular the effects of car-based transportation on air pollution, obesity and physical activity, and deaths and injuries from collisions.

The United States consumes on average approximately 9 million barrels of gasoline and 4 million barrels of diesel fuel every day. Annually, this amounts to approximately 450 gallons of gasoline per American, more than five times the consumption rate of the average European. Our exceptional oil consumption is driven by transportation and the relative inefficiency with which we move people and goods — due both to stagnant vehicle fuel economy and a transportation system that provides few alternatives but to drive a car or truck.

A large part of the health costs of oil are from tailpipe emissions. Pollutants such as particulate matter (especially from diesel exhaust), nitrogen oxides, carbon monoxide, and sulfur dioxide have numerous documented impacts on mortality and health due to cancer, asthma, emphysema, and other respiratory and cardiovascular diseases. While the amount of air pollution produced by individual cars and trucks has been reduced dramatically since the Clean Air Act was first passed in 1971, the number of miles driven by automotive vehicles and the amount of traffic congestion has steadily increased at the same time.

Recent and long-term research on the health impacts of air pollution from automobiles shows that air quality-health “hotspots” — where high traffic volumes overlap with concentrations of exposed people — have persisted and grown in many U.S. metropolitan areas. A recent National Research Council study estimated that the health costs of transportation emissions total approximately $56 billion per year. More than 90 percent of this dollar amount was associated with the value of years of life lost to premature death caused by automotive air pollution.

Transportation strategies that reduce car travel and at the same time increase walking, biking, and public transportation have an added health benefit of reducing obesity and illnesses associated with physical inactivity. According to studies by researchers at the University of Wisconsin, obesity now exceeds smoking as a leading cause of premature death and disease.

Finally, strategies to curb overall travel demand and shift travel to non-automobile modes would not only reduce oil consumption, but would have large health and safety benefits from reducing car and truck collisions. The number of deaths and injuries from car and truck accidents is strongly correlated with the amount that cars and trucks travel.

The American Public Health Association reports that physical injury from vehicles is among the leading causes of death and injuries and estimates that medical costs associated with these deaths and injuries totals more than $100 billion per year.