Impact Of Transport & Vehicle Pollution On The Environment, & Humans (Health & Safety)

Of all the industries/sectors in society, transport is one of the most impactful in a few different ways.

In this guide, we outline the impact of transport and vehicle pollution on the environment, and humans (health and safety).


Summary – What Is The Impact Of Transport & Vehicles On The Environment?

The Environment

A very large portion of the environmental impact of transport and vehicles happens at the fuel combustion stage.

The result of combustion is mainly climate change/global warming via the emission of greenhouse gases, and a decrease in air quality via the release of regular air pollutants/chemicals like particulates, carbon monoxide and more.

Apart from these direct impacts, there are also many indirect impacts like water pollution via acid rain or via urban road runoff (of oil and car liquids into natural water sources and the ocean).

There’s also water, waste and other footprints to consider from different modes of transport at different stages of their lifecycle.

Passenger vehicles have actually become more efficient over the last few decades, but, numbers indicate that total miles driven and the total number of vehicles on the road have increased.



There’s two main effects of vehicle pollution on humans and human health:

Direct impact – via air pollution from vehicle emissions, leading to decreasing air quality – which humans breathe in/inhale. Noise pollution may also be an issue for some

Indirect impact – via greenhouse gases from vehicle emissions, leading to climate change and global warming – which can impact a range of other industries (agriculture is one such example via a change in rainfall patterns, growing seasons, frequency of droughts etc.)


The impact can also happen in the short term, but also the long term (e.g. some respiratory or cancer related diseases might take years and decades to develop and show serious symptoms)


How Transport & Vehicle Pollution Impacts The Environment

Lifecycle Of Vehicles – Not Just Operation & Combustion Of Fuel

Some people just look at the combustion of fossil fuels and gasoline/petrol for the impact of vehicle pollution.

But, a more accurate picture of total impact involves looking at the lifecycle of the car. For example:

You need steel, rubber, glass, plastics, paints and other materials to make a vehicle – these materials have to be mined (mining causes degradation which can be irreversible), sourced, fabricated, transported (in the case of oil – there can be water oil spills).

Then there’s manufacturing of the vehicles (there’s a carbon/energy footprint, and waste from manufacturing – including the water footprint of waste water)

Then operation (combustion of fossil fuels leads to carbon emissions and air contaminants being released)

Then disposal/recycling – Plastics, toxic battery acids, and other products may stay in the environment. Fortunately, junkyard pile-ups are becoming much smaller than they were in the past. About three-quarters of today’s average car, including the bulk of a steel frame, can be recycled. (


  • Most of an automobiles’ environmental impact, perhaps 80 to 90 percent, will be due to fuel consumption and emissions of air pollution and greenhouse gases that climate scientists say are driving global warming.
  • Fortunately, the level of that impact is very much under the control of the driver.



Water Footprint Of Vehicles

  • It takes about 39,000 gallons of water to produce the average domestic car, including the tires (Major water uses in the automotive manufacturing industry include surface treatment and coating, paint spray booths, washing/rinsing/hosing, cooling, air conditioning systems and boilers)


Carbon Footprint Of Vehicles

  • The carbon footprint of a vehicle varies depending on the type of vehicle it is
  • But, there’s a direct and indirect carbon footprint
  • The direct carbon footprint can be measured from tailpipe emissions, or in the case of electric cars, the emissions from the energy source
  • The indirect carbon footprint comes from mining and sourcing materials (for both the car parts, and the fossil fuels or energy sources that run it), shipping and transporting, pumping and refining, fabrication and manufacture, dumping/disposal or recycling etc.
  • Indirect CO2 emissions can run into the thousands of pounds of CO2
  • However, most of the carbon footprint comes from operation
  • Of the roughly 126,000 pounds of CO2e emitted in a car’s lifetime (assuming 120,000 miles for a 1995 mid-sized sedan), 86% is from burning fuel. (-


Air Pollution

Air pollution is the non GHG release of air contaminants from vehicles, and vehicles and city based transport (cars and trucks) are one of the leading causes of air pollution.

Air pollution leads to decrease in air quality, which causes health issues for humans.


  • Ingredients of vehicular air pollution are ozone, particulate matter, nitrogen oxides, carbon monoxide, sulfur dioxide, and toxics.

Read more at 


  • By reducing transportation emissions globally, it is predicted that there will be significant positive effects on Earth’s air quality, acid rain, smog and climate change.


  • Vehicles are America’s biggest air quality compromisers, producing about one-third of all U.S. air pollution.
  • There’s smog, carbon monoxide, and other toxins emitted by vehicles 



  • … carbon-dioxide, carbon-monoxide, oxides of nitrogen exacerbate the already deteriorating ozone layer.
  • The harmful particles that remain suspended in our atmosphere impact the quality of air that we breathe in leading to numerous respiratory diseases and cancers
  • respiratory diseases and cancers can occur as a result of poor air quality



Cars are responsible for [in Melbourne in Australia] …

  • 72 per cent of all carbon monoxide (CO) emissions
  • 70 per cent of all nitrogen oxides (NOx) emissions
  • 28 per cent of all volatile organic compounds (VOC) emissions
  • 31 per cent of all emissions of particles smaller than 2.5 microns (PM2.5)
  • 27 per cent of all emissions of particles smaller than 10 microns (PM10)
  • 6 per cent of all sulfur dioxide (SO2) emissions

Nitrogen oxides (NOx) and volatile organic compounds (VOCs) can combine to form ozone (summer smog).

Particle emissions can build up in the air to form autumn/winter smog in the cooler months. Both diesel and petrol vehicles emit particles into the air.

Despite increasing use of motor vehicles, their emissions have been dropping since 1990. EPA’s air monitoring stations have found nitrogen dioxide (NO2) and carbon monoxide (CO) levels have been steadily reducing since monitoring began. The number of summer smog days in Melbourne has decreased from 18 events per year down to about one event every two years



  • [Both primary and secondary reactionary air pollution results from the use of vehicles and transport]
  • While new cars and light trucks emit about 90 percent fewer pollutants than they did three decades ago, total annual vehicle-miles driven have increased by more than 140 percent since 1970 and are expected to increase another 25 percent by 2010.
  • The emission reductions from individual vehicles have not adequately kept pace with the increase in miles driven and the market trend toward more-polluting light trucks, a category that includes sports utility vehicles (SUVs).
  • As a result, cars and light trucks are still the largest single source of air pollution in most urban areas, accounting for one quarter of emissions of smog-forming pollutants nationwide.



Climate Change/Global Warming

  • From release of carbon dioxide and nitrous oxide from from combustion of petroleum/oil based fuel
  • Can also occur from coal and fossil fuel combustion for EV electrical supply


Water Pollution

Includes but isn’t limited to:

  • Acid rain (smog from contaminants released from car exhausts + rain combine to create acid rain which drops into water sources like the ocean and natural water sources like lakes and rivers)
  • Oil spills from ships and tankers
  • Urban/road run off from vehicles which finds it’s way into water sources – this is one of the major sources of water pollution
  • Underground fuel storage tanks can leak and create water pollution



Other Pollution

  • The effects of car pollution are widespread, affecting air, soil and water quality.
  • Nitrous oxide contributes to the depletion of the ozone layer, which shields the Earth from harmful ultraviolet radiation from the sun.
  • Sulfur dioxide and nitrogen dioxide mix with rainwater to create acid rain, which damages crops, forests and other vegetation and buildings.
  • Oil and fuel spills from cars and trucks seep into the soil near highways, and discarded fuel and particulates from vehicle emissions contaminate lakes, rivers and wetlands.




  • Fossil fuels like oil (for gasoline/petrol) and coal (for EVs) – are finite
  • This raises sustainability issues as we consume more of the remaining supply


Land Use, Land Footprint, Erosion & Degradation

  • Roads and transport infrastructure increases urban sprawl and land use footprint of vehicles as we build more highways and other infrastructure
  • Mining fossil fuels and car materials also has a land footprint and can permanently impact land use


Some Stats On Environmental Pollution Caused By Transport

  • Globally, transport is responsible for 14% of greenhouse gases compared to other sectors



  • Overall, in towns and cities, the main source of air pollution is road transport 
  • Vehicular exhaust contributes to the majority of carbon monoxide let into our atmosphere
  • Particle pollution [particulate matter] mainly comes from motor vehicles, wood burning heaters and industry 
  • [Ozone is] formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources chemically react in the presence of sunlight
  • Most of the nitrogen dioxide in cities [in Australia] comes from motor vehicle exhaust (about 80%)
  • [in terms of VOCs in the UK, majority] comes from transport, including distribution and extraction losses – 50% of total



Variables To How Much Transport & Vehicles Impact The Environment

Variables to how much the transport sector might impact the environment might include:

Whether you are measuring a direct impact, or indirect impact/effect

The mode of transport you are measuring – big car, small car, truck, train, ship, airplane etc.

The type of vehicles you are talking about – conventional internal combustion engine, electric vehicles, hybrid vehicle, hydrogen vehicle

Type of fuel the vehicle runs on

The energy source the fuel comes from (coal, natural gas, oil, renewables etc)

Number of vehicles on the road (and planes in the air, trains on tracks, ships in the water etc.)

How far they drive each day (as a total average)

Number of passenger in the vehicles (the more people in the vehicle – the lower the per passenger pollution rate is)

Fuel efficiency of the vehicle

Features and technology the vehicle has to lower pollution (lighter weight, tail pipe filter, regenerative braking etc.)

Must consider full lifecycle of vehicle (and not just operation/combustion) – sourcing/mining materials and petroleum/oil, manufacture, operation, disposal/recycle


How Transport & Vehicle Pollution Impacts Humans

Vehicles (via fuel combustion) emit common air pollutants, but also greenhouse gases.

Air pollutants (like particulates, carbon monoxide etc.) can decrease air quality, but also cause smog (which can lead to acid rain) and a range of other issues.

Air pollutants and decrease in air quality, particularly in cities and heavily populated areas with a high density of vehicles, have been linked to respiratory diseases, cancers and other health issues for humans.

In heavily built up areas, noise pollution can also be an issue.

In terms of greenhouse gases, combustion of fuel can emit carbon dioxide and nitrous oxide – both warming agents for the climate. This is more a long term issue though, whereas air pollution can be immediate.


  • Congested traffic and major roadways make things worse [compared to quieter open roads and traffic ways] … traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. 



  • Poor air quality increases respiratory ailments like asthma and bronchitis, heightens the risk of life-threatening conditions like cancer, and burdens our health care system with substantial medical costs.
  • Particulate matter is singlehandedly responsible for up to 30,000 premature deaths each year.
  • Passenger vehicles are a major pollution contributor, producing significant amounts of nitrogen oxides, carbon monoxide, and other pollution.
  • In 2013, transportation contributed more than half of the carbon monoxide and nitrogen oxides, and almost a quarter of the hydrocarbons emitted into our air.



  • Particulate matter, hydrocarbons, carbon monoxide and other car pollutants harm human health. 
  • Other car pollutants that harm human health include sulfur dioxide, benzene and formaldehyde

Read more at 


  • In Australia…
  • In addition to greenhouse gases, petrol and diesel powered cars also spew a wide range of toxins into the air which people then suck into their lungs. 
  • It is estimated that vehicle pollution kills over 1,000 Australians per year. 
  • Last year there were under 1,300 road accident fatalities so air pollution from cars could be killing more people than car crashes and could be costing Australia over $10 billion a year.
  • If we assume the amount is $10 billion, then with around 1.2 million cars sold in the country each year we could spend $8,000 ensuring each new car sold is electric and the country could still come out ahead overall on cost. 
  • Toxic vehicle pollution would be greatly reduced if fuel-efficient hybrids were used, but would not be eliminated.



Another resource about the potential impacts of vehicular pollution ingredients on human health can be found and read at 


We’ve also written previously about some of the effects of outdoor air pollution (with transport being a big contributor) on humans and human health.
















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