The price of automobiles doesn't begin to pay for the many indirect costs: waste of land and energy,loss of amenities,and the expenses of traffic enforcement, pollution and the cost of accidents by uninsured drivers...Society should stop paying the subsidies that keep this endless loop turning."
-Jane Jacobs. The Nature of Economics. Random House. 2000
Neurotoxins and Carcinogens in Car Exhaust
Most people are familiar with global warming, smog and acid rain. But few of us realize that gasoline contains the neurotoxin manganese(see http://www.epa.gov/oms/regs/fuels/additive/mmt_cmts.htm) and the carcinogen, benzene.
Cars burn a mixture of octanes, compounds containing carbon and hydrogen. Oxidize such compounds and, among many other things, you will generate CO2. Since there is no practical filter for carbon dioxide, all emissions end up in the environment, where they contribute to global warming.
Cars have internal combustion engines. High temperatures within such engines cause a reaction between the two major components of air: oxygen and nitrogen. The resulting compounds known as nitrogen oxides lead to nitric acid formation by reacting with hydroxyl radicals in the air. Nitric and sulfuric acids are the two major components of acid rain.
Nitrogen oxides also dissociate in sunlight to form ozone, a compound which is useful in the stratosphere. The problem is that it never gets there.Instead it remains at ground level where it is poisonous. In addition, nitrogen oxides react with hydrocarbons in the air to form peroxyacyl nitrates (PANS), constituents of smog.
Although catalytic converters attempt to reverse the oxidation of nitrogen, they are not 100% efficient, so cars equipped with such gadgets continue to contribute to both acidic precipitation and smog, both of which claim the lives of those who suffer from respiratory diseases.
Cars with air conditioners have compounds that dissociate to form halogen free-radicals ( reactive atoms or compounds with unpaired electrons), especially if they contain now-illegal freons. ( The latter persist on the black market.) These radicals break down ozone while being recycled in the net reaction. As a result they are available to break down more ozone, implying that small amounts of , for instance, Cl can destroy large amounts of ozone.
As citizens become excessively dependent on automobiles, an exaggerated amount of land is devoted to these archaic inventions. The environment loses green spaces and public squares to highways and parking lots. The latter affect a city's microclimate. Asphalt aborbs solar energy, raising already uncomfortable summer temperatures in urban centres.
This seems to be an accepted fact of life and rarely raises an eyebrow unless it affects immediate family members. The truth is cars have a higher per passenger mortality rate than trains, buses and commercial aircraft.