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.


Currently, there are about 1 billion cars on the road globally. That number is projected to double by 2050, with much of the growth coming from sales of second hand vehicles in lower-income countries. Transportation already accounts for one-quarter of humanity’s carbon-dioxide emissions, which are rapidly heating the planet. And in many African cities, cars and trucks have become a dominant source of outdoor air pollution, which already kills more than 3 million people worldwide each year.

Personal vehicles are indeed a major cause of global warming.  Collectively, cars and trucks account for nearly one-fifth of all US emissions, emitting around 24 pounds of carbon dioxide and other global-warming gases for every gallon of gas. About five pounds comes from the extraction, production, and delivery of the fuel, while the great bulk of heat-trapping emissions—more than 19 pounds per gallon—comes right out of a car’s tailpipe.

Recognizing the fact that passenger cars are a major polluter, car manufacturers as well as the policy makers around the world making constant efforts to decrease car emissions and these efforts can be classified into the following two categories:

The European Union (EU) has set the most challenging targets for reducing vehicle CO2 emissions in the world.  They are making improvements to engine combustion and fuel management, such as variable value timing, turbo charging, stop-start systems, and direct engine injection technology and vehicle weight reduction, to mention few.

New or Future Cars: Here are a couple of points:

  • Car manufacturers around the world are committed to carbon neutrality and constantly making improvements with the focus to reduce car emissions.  For instance, the European car manufacturers acknowledge that passenger cars count for 60.7 percent of total CO2 emissions from road transport in Europe. 
  • The good news is that the European car manufacturers such as Renault, Volvo, PSA, Daimler, BMW and Volkswagen have already set ambitious targets towards carbon neutrality and aligned their business strategies with an ever-accelerating push for electrifying their product portfolios; and

Old or Used Cars: Here are a couple of points:

  • Transport leaders from around the world met in 2017 in Geneva for the first time to discuss the flood of non-fuel efficient and unsafe second hand vehicles into developing countries and taken the first steps toward agreeing voluntary regulations and standards on the often secretive trade.  At a side meeting organized by the Inland Transport Committee, which is part of the United Nations Economic Commission for Europe (UNECE), delegated from 90 nations, including approximately 30 developing countries, gathered to share information.
  • Almost all major countries implemented a mechanism in their countries to reduce car emissions by conducting smog or emissions inspections as frequently as possible.  Vehicles that are manufactured in these countries have a federal emission standard that has to meet and that onboard computer is designed to warn the driver of any system or any failure that would alter that.  Technicians check what’s called “monitors” — essentially test cycles of various systems.  The whole idea is the computer has to keep an eye on all the management systems and make sure they’re functioning properly.  An emission test is passed or failed based on how each of those monitors perform. 

Unfortunately, millions of used cars, vans and minibuses exported from Europe, the USA and Japan to low- and middle-income countries are hindering efforts to combat climate change. They are contributing to air pollution and are often involved in road accidents. Many of them are of poor quality and would fail road-worthiness tests, if they have any, in the exporting countries.


Here is a fact: Most developing countries where these used vehicles are exported to, have limited or no regulations on governing the quality and safety of imported used vehicles and rules which do exist are often poorly enforced. Equally, few developed countries have restrictions on the export of used vehicles.


A report published in October 2020 by the United Nations Environment Programme (UNEP), looks at 146 countries that import used vehicles, and calls for action to regulate the trade through the adoption of a set of harmonized minimum quality standards. These would ensure used vehicles contribute to cleaner and safer fleets in recipient countries. UNEP and partners will address these issues, initially with a project focused on Africa.

Here are a few key findings of the report:

  • The three largest exporters of used vehicles, the European Union (EU), Japan, and the United States of America (USA), exported 14 million used light duty vehicles (LDVs) worldwide between 2015 and 2018. The EU was the largest exporter with 54 per cent of the total followed by Japan (27 per cent) and the USA (18 per cent);
  • The major destinations for used vehicles from the EU are West and North Africa; Japan exports mainly to Asia and East and Southern Africa and the USA mainly to the Middle East and Central America;
  • Seventy percent of exported LDVs head to developing countries. Africa imported the largest number (40 per cent) in the period studied followed by Eastern Europe (24 percent), Asia-Pacific (15 percent), the Middle East (12 percent) and Latin America (nine percent);
  • The global fleet of LDVs is set to at least double by 2050. Some 90 per cent of this growth will take place in non-OECD (Organization for Economic Co-operation and Development) countries which import a large number of used vehicles. Despite the critical role they play in road accidents, air pollution, and efforts to mitigate climate change there are currently no regional or global agreements on the trade and flow in used vehicles; and
  • Of the 146 countries studied, 66 limit the age on imported vehicles. These age restrictions are popular partly because they can be easily enforced. They tend to vary from three to 15 years.

The report identified the following challenges:

  • Pollutant and climate emissions of used vehicles;
  • The quality and safety of used vehicles;
  • Energy consumption; and
  • Costs to operate used vehicles.

Here are the recommendations made by this report:

  • More research is needed to detail further the impacts of the trade in used vehicles, including that of heavy duty used vehicles;
  • At global and or regional level harmonized regulations should be developed that regulate the trade in used vehicles to put an end to the trade of obsolete, unsafe, dirty, and faulty used vehicles. The regulation should encompass measures to ensure used vehicles make meaningful contributions towards shifting to cleaner, safer, and affordable mobility;
  • Regulations should be gradually tightened in the coming decade. Used low and no emissions vehicles should be promoted as an affordable way for middle- and low-income countries to access advanced technologies;
  • Exporting and importing countries have a shared responsibility to improve and regulate used vehicles to minimize their negative impacts; and
  • A strong implementation and enforcement mechanism should be introduced to check compliance and enforcement of the agreed regulations.

The message of the report is loud and clear:

  • Developed countries must stop exporting vehicles that fail environment and safety inspections and are no longer considered roadworthy in their own countries, while importing countries should introduce stronger quality standards.

Here is the warning:

  • If left unsupervised, the global trade in used vehicles could have stark consequences for both climate change and public health in the decades ahead, the report’s authors said.

Perhaps there is a need to keep reminding the countries involved in the global trade of used dirty vehicles car pollutants cause immediate and long-term effects on the environment. Car exhausts emit a wide range of gases and solid matter, causing global warming, acid rain, and harming the environment and human health. Engine noise and fuel spills also cause pollution.

The good news is that a few countries have started taking steps to crack down on the oldest and dirtiest used cars: Kenya, a rapidly growing market, now accepts only imports of vehicles younger than 8 years old, mainly from Japan. As a result, its vehicle fleet is about one-third more fuel-efficient than that of neighboring Uganda, which only last year set an age limit of 15 years for its imported cars.

Kanata, Ontario, Canada 03 March 2021