Cars affect many people not just drivers and car passengers. The externalities of automobiles, similarly to other economic externalities, are the measurable difference in costs for other parties to those of the car proprietor, such costs not taken into account when the proprietor opts to drive their car. According to Harvard University, the main externalities of driving are local and global pollution, oil dependence, traffic congestion
and traffic collisions; while according to a meta-study conducted by the Delft University these externalities are congestion and scarcity costs, accident costs, air pollution costs, noise costs, climate change costs, costs for nature and landscape, costs for water pollution, costs for soil pollution and costs of energy dependency.
Some say that road users should pay for their pollution.
The negative externalities can be substantial, since the driver does not take into account, for example, the negative effects of air pollution on third parties, when they opt to drive their car. Legislators and regulators can internalize those external costs, either by taxes on fuels for example, either by any kind of limitation to car usage, such as parking meters or urban tolls. Nevertheless, it seems the drivers in some countries, already pay some external costs with taxes. Road taxes in the Netherlands for instance, have a relatively high yearly value, which covers the maintenance of the infrastructures. Nevertheless, in the majority of western nations, the external costs of driving, are not covered totally either by taxes, or by any kind of car usage limitation.
Increased reliance on the automobile leads to increased road congestion. While expansions in road capacity are often touted as relieving congestion, induced demand often means that any reductions in congestion are temporary.
Cars are the leading cause of fatal collisions in many countries, and are the leading cause of death of youth and children. In 2010, car crashes in the United States resulted in 32,999 deaths and a projected $871 billion cost to society, around 6% of the United States 2010 GDP.