All the ways car dependency is wrecking us – car harm: a global review of automobility's harm to people and the environment

Ray Delahanty ("CityNerd") is a transportation engineer based in the United States who has recently taken an interest in making content about urban planning on YouTube for a wider audience. In this video, Delahanty discusses a 2024 paper by Patrick Miner et al. which categorizes and explains each of the problems that result from widespread automobile use globally.

Delahanty's video summary is engaging and non-technical, but I encourage you to read the paper itself, which is very good. As he remarks, it is well-written and actually pretty accessible as scientific literature goes.

Car harm: A global review of automobility's harm to people and the environment

Abstract (emphasis mine):

Despite the widespread harm caused by cars and automobility, governments, corporations, and individuals continue to facilitate it by expanding roads, manufacturing larger vehicles, and subsidising parking, electric cars, and resource extraction. This literature review synthesises the negative consequences of automobility, or car harm, which we have grouped into four categories: violence, ill health, social injustice, and environmental damage. We find that, since their invention, cars and automobility have killed 60–80 million people and injured at least 2 billion. Currently, 1 in 34 deaths are caused by automobility. Cars have exacerbated social inequities and damaged ecosystems in every global region, including in remote car-free places. While some people benefit from automobility, nearly everyone—whether or not they drive—is harmed by it. Slowing automobility's violence and pollution will be impracticable without the replacement of policies that encourage car harm with policies that reduce it. To that end, the paper briefly summarises interventions that are ready for implementation.

In this context, "automobililty" refers to the use of an automobile vehicle (informally a "car") to travel, not to the concept of physically moving oneself with one's body.

Sections of the article include:

• The death toll of automobility: "car harm has grown to be so ubiquitous that it is socially constructed as normal, accidental, or inevitable ... cars and the system of automobility have killed approximately 60 to 80 million people ... [which] is similar in magnitude to the combined 57 to 82 million deaths from the two World Wars"
• Violence:
  • Crashes: "Traffic crashes kill 1.3 million people per year or 3500 people per day, and they are the eighth‑leading cause of death globally ... Globally, traffic crashes are the leading cause of death for children over 4 and for adults under 30 ... Crashes kill more than 700 children every day ... children walking to school or playing with friends must 'watch out and make way, or be killed' ... Since 2000, an estimated 2 billion people have been injured in motor vehicle crashes—up to 1 in 4 people alive today—not accounting for repeat injuries or population change."
  • Intentional violence: "In car-dependent societies, cars blend into their surroundings and can be inconspicuous weapons ... Hundreds of cities have installed bollards to fortify their public spaces against vehicle attacks ... Other forms of intentional car-based violence include aggressive driving, driving under the influence of alcohol, and drive-by shootings"
• Ill health: "Cars and automobility negatively affect physical and mental health through a variety of mechanisms including pollution, sedentary travel, and social isolation"
  • Pollution: "Automobility contributes to air, land, and water pollution. These forms of pollution are harmful to human health and contribute to hundreds of thousands of premature deaths per year."
    • Air, land, and water pollution:
      • "Traffic-related air pollution is a mix of gases and particles ... Motor emissions are produced by the running of a vehicle's engine. Abrasion emissions are caused by the friction of materials such as tyres, brakes, and road surfaces ... The manufacturing and disposal of vehicles also contribute to ambient air pollution ... A systematic review of 353 studies found that traffic-related air pollution is associated with 'all-cause, circulatory, ischemic heart disease and lung cancer mortality' ... Vehicular air pollution may increase risk of neurological conditions including depression, anxiety, dementia including Alzheimer's, schizophrenia, autism, and cognitive impairment ... It contributes to low birth weights and premature births ... and in children it contributes to reduced lung volumes and increased risk of diseases, e.g. asthma and leukaemia, and mental health issues."
      • "Vehicle tyres and brakes, as well as road markings, shed microparticles including microplastics which become airborne and can contaminate food or water ... effects may include inflammation, cellular damage, gastrointestinal issues, and effects from the accumulation of heavy metals that attach to microplastics ... Automobility sources of metals that contaminate environments include exhaust, tyres, brakes, clutches, lubricating oils, vehicle corrosion, road surfaces (e.g. asphalt), and road markings ... The authors noted that brakes and tyres were especially potent contributors of metal contaminants in road dust. As such, increased uptake of heavy electric vehicles will maintain or increase these levels of metal contamination." We all know by now how bad the air pollution is (well, in theory, but we pretend it's not an issue in practice; otherwise you would seriously be up in arms about it), but there is basically no public perception of how bad the tire microplastic issue is. Please read my commentary on tire microplastic pollution for more analysis of this issue, as well as the many excellent sources cited in this paper.
      • "About 75% of current global lead consumption is for motor vehicle batteries ... Lead is also found in paint for both new and older vehicles ... Road markings contain high concentrations of lead, especially in yellow paint ... Oils from streets contaminate land and water, especially in the form of runoff after precipitation events ... People who come into contact with spilled oil, breath its vapours, or eat oil-contaminated seafood are at risk for dizziness, nausea, neurological issues, and cancer"
    • Noise pollution: "Motor vehicles are the main source of noise pollution in urban areas ... The negative health effects of vehicular noise pollution include cardiovascular disease, high blood pressure, tinnitus (ringing in the ear), hearing loss, anxiety, stress, sleep disturbance, and cognitive impairment ... A European Environment Agency report estimated 10,100 premature deaths per year due to road noise pollution in 32 European countries"
    • Light and thermal pollution: "Automobility contributes to light and thermal pollution through car-centric built environments. Streets and car parks (parking lots) generate light pollution that interferes with human health, e.g. sleep quality ... Paved surfaces such as streets and parking spaces increase local air and surface temperatures. This “urban heat island” effect harms human health by exacerbating heat waves, increasing air pollution, causing heat-related conditions (e.g. heat stress and heat stroke), and worsening existing conditions (e.g. cardiovascular or respiratory diseases)"
  • Sedentary travel: "Sedentary behaviour, including car travel, increases the risk of 'all-cause mortality, cardiovascular disease mortality… cancer mortality, and incidence of cardiovascular disease, type 2 diabetes, and cancer' ... In car dependent places, many short journeys are made by car when they could be made by physically active modes."
  • Dependence and isolation:
    • "In car-dependent landscapes, individuals are isolated from people and destinations by long distances and physical barriers such as motorways (expressways). Without a car, one cannot access food, healthcare, work, education, family, or friends. Most people on the planet do not drive, including millions in car-dependent places. This results in social isolation, and 'isolated individuals are at increased risk for the development of cardiovascular disease, infectious illness, cognitive deterioration, and mortality' ... Emergency services can also be impacted by sprawling car-dependent landscapes as evidenced by fire and ambulance response time delays caused by road traffic and increased travel distances"
    • "Compared to children who walk or cycle, children who travel in cars have less knowledge about their neighbourhoods, have fewer opportunities for outdoor play and exploration, and gain less experience in assessing risk and becoming independent"
    • "Each time someone prepares to cross a street, they are engaging in a life-and-death decision process. The danger and unpleasantness of traffic reduces rates of walking and cycling and therefore physical activity which is essential to good health"
• Social injustice: "Automobility is enabled by and produces a long list of social injustices. These include unevenly distributed harm, inaccessibility, and the consumption of space, time, and resources"
  • Unequal distribution of harm:
    • "In terms of age, more than 700 children are killed in traffic crashes every day, and children and the elderly are more likely than other pedestrians to be killed in crashes ... Crashes are the leading cause of death for people aged 5 to 29"
    • "In Brazil and the US, two large racially and ethnically diverse countries, crashes disproportionately kill Black and Indigenous people ... A US study found that people were less likely to stop their cars for Black pedestrians than for white pedestrians ... Automobility often conflicts with and endangers Indigenous practices of walking as transport"
    • "...when a woman is involved in a car crash, she is 47% more likely to be seriously injured than a man, and 71% more likely to be moderately injured, even when researchers control for factors such as height, weight, seat-belt usage, and crash intensity. She is also 17% more likely to die ... Traffic crashes are 'the main cause of injuries and trauma in pregnant women' and 'more than half of all pregnancy trauma are due to [crashes]'"
    • "Despite lower levels of car ownership and fewer kilometres travelled, the economically poor are more likely than the economically wealthy to be killed in traffic crashes ... The least wealthy members of our societies do not have cars but are forced to endure elevated levels of crashes and pollution so that wealthier people can drive."
  • Inaccessibility:
    • "...car infrastructure creates obstacles for people with mobility disabilities, e.g. pavement (sidewalk) clutter such as parking meters, driveway [curb] cuts, and bollards to guard against unsafe driving. [Curb] cuts for crossing streets, which originated as an 'accommodation' for people in wheelchairs, can be a barrier for people who are blind or have limited vision, especially when tactile paving is not used ... People with disabilities are more likely than others to be killed or injured by motor vehicles despite lower levels of car access and higher levels of public transport use"
    • "Car-dependent environments “disable” people who do not drive by restricting access to essential needs ... most disabled people are among the losers, along with people in poor neighbourhoods and children ... Automobility, like many systems, is organised around the assumption of “able-bodied” movement with too few considerations for physical and social accessibility."
  • Consumption of space, time, and resources: "Automobility consumes a large amount of space for the operation and storage of motor vehicles"
    • Car-dependent places: "Automobility enables the geographical separation of home, work, schools, hospitals, shops, parks, and other places so that motor vehicles are the most convenient way to move between them. In this way, automobility is a solution for a problem that it helps to create"
    • Streets and motorways (expressways):
      • "While moving, cars consume an estimated 1.39m2 per hour per person compared to 0.52m2 for bicycles, 0.27m2 for walking, and 0.07m2 for buses ... One person in a car consumes the space of about 20 bus passengers, and cars are consuming more and more space as vehicle sizes increase."
      • "Among roadways, motorways are some of the most space and resource-intensive. Not only do they cost millions of pounds per kilometre, they displace residents and destroy communities as they cut paths through the landscape ... From 1957 to 2010, construction of US motorways cost at least US$1.4 trillion and required the movement of 38 billion metric tons of earth—equivalent to 116 Panama Canal construction projects. These motorways displaced an estimated 1 million people from their neighbourhoods"
    • Parking [vehicle storage]:
      • "On-street parallel parking consumes approximately 10-19 m2 per car and off-street parking consumes about 25-33 m2 per car ... By contrast, a person standing, sitting in a wheelchair, or stationary on a bicycle consumes approximately 1-2 m2. An empty car in a car park consumes the space of about 20 people."
      • "Some governments have minimum parking “requirements” or mandates that legally obligate property owners to supply a certain number of parking spaces for each building. These mandates frequently result in car parks (parking lots) that consume more land than the buildings to which they are attached"
    • Housing: "Automobility increases the cost of goods and services ... one parking space is often larger than a person's living space. One off-street parking space consumes 25-33 m2 which is about the same size as the average living space per person in China, South Korea, or Spain ... Homes in car-dependent places are often built and sold with off-street parking in a garage, car park (parking lot), or drive. Bundling parking with housing inflates the cost of housing and obscures the true cost of automobility ... In an affordable housing development in California, bundled parking raised construction costs by 38% despite an exception that allowed the construction of fewer parking spaces"
    • Time: "As more people drive, the roads fill up thereby making it more difficult for each individual to drive. ... As Ivan Illich noted in the 1970s, “the typical American male” spends 4 out of 16 waking hours driving or gathering money to pay for a car." That is 25% of your waking life devoted to car-dependency. Wouldn't you rather live 25 more healthy, wonderful years?
    • Financial burden: "Car-dependent places force people to own cars so they can access essential destinations ... Even in countries with high tariffs on fuel, motorists cannot cover the cost of automobility. A study in Australia found that 10% of parking was covered by the motorist while the rest was externalised, and the motorist's “out-of-pocket costs” were just one-sixth of the total trip cost ... cars cost society €0.11 per kilometre while walking and cycling provide a positive benefit (mainly via health effects) of €0.37 and €0.18 per kilometre"
• Environmental damage: "Automobility has contributed to the transgression of at least four of these boundaries: climate change, biosphere integrity, land system change, and novel entities. Automobility is a leading source of anthropogenic carbon emissions, and it damages ecosystems and habitats, consumes natural resources, and worsens natural disasters"
  • Carbon emissions:
    • "In 2019, transport “accounted for 23% of global energy-related CO2 emissions. 70% of direct transport emissions came from road vehicles,” and transport-related carbon emissions are rising"
    • "...internal combustion engine vehicles produce most of their emissions in the operation stage, with 23–32 t of CO2, and the production stage, with 5–10 t. Electric vehicles produce most of their emissions in the fuel or electricity provision stage, with 11–20 t, and the production stage, with 9–14 t"
    • "...automobility infrastructure includes streets, parking, and other spaces. Building and maintaining this infrastructure generates substantial carbon emissions ... sprawling land uses can also increase carbon emissions in non-transportation sectors"
    • "Technologies likely to be core to lower-carbon futures such as district heating and cooling systems only operate efficiently in high density areas"
  • Pollution and resource extraction:
    • "Oil is used to produce fuel and to produce plastics for vehicle manufacturing. The use of plastics in vehicles is increasing due to the low weight of plastics compared to metals. This means that plastics help reduce vehicle weights and therefore the energy needed to move them. However, plastics are made from petrochemicals and are a major source of carbon emissions and pollution"
    • "Mining activities for metals used in vehicle manufacturing influence several environmental areas of concern including 'air quality, water quality / quantity, acid mine drainage, land impacts, [and] ecological impacts'"
    • "In the end-of-life stage, economically valuable (e.g. copper) and hazardous (e.g. fuel) elements are removed from vehicles. The remaining plastic, glass, and other materials are cut into automotive shredder residue. About two thirds of this residue is sent to landfill and most of the remaining is incinerated"
    • Tyres [tires]:
      • "Approximately 2 to 3 billion tyres are manufactured annually and they are not biodegradable ... These materials are mostly derived from fossil fuels ... In the end-of-life stage...they are incinerated; or they are placed in landfills or stockpiles"
      • "Metals and microplastics from tyres and brakes pollute terrestrial, marine, and freshwater ecosystems and contribute to the transgression of the novel entities planetary boundary. Among primary microplastics (particles released directly rather than from the breakdown of larger plastics) released into the ocean, tyres and road markings account for an estimated 35% ... In an Arctic ice (firn) core with a bottom dating back to c. 1966, tyre particles constituted 24% of observed plastic particles"
      • "One of the substances found in tyres has been killing salmon in the north-western US for several decades."
    • Other pollution: "Applying road salt to melt ice and snow is contaminating freshwater ecosystems and making some water sources unsafe for drinking ... Traffic-related noise pollution harms wildlife through physical effects, e.g. hearing damage, and through behavioural effects, e.g. breakdowns in communication such as birdsong obscured by traffic noise"
  • Land use: "Vertebrate deaths from road traffic are difficult to count, but the global number is likely greater than 1 billion per year ... Roads and sprawl, or car-based low-density development, contribute to deforestation and declining biodiversity ... These types of development exacerbate natural disasters ... Sprawling development also alters the patterns of wildfires"

The paper suggests a number of interventions which we could take to reduce the negative impacts of automobiles on the world and society, including:

• Congestion charges / road pricing
• Reductions to on-street parking
• Car-free or car-limited areas
• Reduced traffic speeds
• Replacing minimum parking mandates with maximums
• Converting parking structures into homes, shops, etc.
• Ciclovía / open streets
• Electric bikes / micromobility
• Car sharing

The authors are also very clear to note that electric vehicles solve almost none of them problems that cars create:

Although switching to electric vehicles may be less politically controversial than reducing car use, electrification fails to address a majority of the harms described in this paper, including crashes, intentional violence, sedentary travel, car dependence and isolation, unequal distribution of harm, inaccessibility, land use, or consumption of space, time, and resources. Electrification has the potential to reduce carbon emissions from motor running, but emissions from vehicle production and the end-of-life phase will remain high—or increase. Electric vehicle production will likely increase the extraction of mined metals. Increased energy demand to charge electric vehicles may delay efforts to decarbonise electric grids.

You are welcome to form your own opinions about your lifestyle, but this ENORMOUS body of research is undeniable. Automobiles cause an incredible amount of damage to society; they unequally distribute this damage to the least privileged and poorest members while benefitting the wealthiest and most advantaged; they criminally destroy natural wildlife habitats and harm the environment; they encourage the destruction of human habitats via dangerous land use, impermeable surfaces, and increased heat; and they cause irreparable damage to the physical and mental health of people around the world, especially vulnerable persons with disabilities, seniors, and children, including billions of deaths and injuries.

It is important to prioritize the well-being of society when making decisions about your own lifestyle and especially when voting for political candidates. I ask that you consider these negative effects of cars more seriously than you probably do now. I hope that this may encourage you to seek changes to your own lifestyle (i.e. the reduction in number of vehicles you own; relocation to a place where cars are not needed; adjustments to your movement patterns to facilitate a car-free or car-lite lifestyle; political votes toward candidates who seek to reduce car dependency; and community engagement with organizations who seek to do the same.

Delahanty suggests that conscientious viewers join local advocacy organizations that may, among other things, seek to improve the design of their communities; reduce car speeds and access; eliminate minimum parking requirements; promote travel by public transit, bicycles, walking, and other forms of micromobility; encourage infrastructure that prioritizes human-scale activity rather than car-oriented activity; support better integration of human habitats into natural wildlife habitats via the removal of some car infrastructure; redesign cities and towns to better withstand natural disasters by reducing infrastructure which reinforces car dependency; and more. I agree with this takeaway and recommend that you do these things.