Motor vehicles are a major source of air pollution. They emit carbon monoxide, hydrocarbons, nitrogen dioxide, particulate matter, and sulfur dioxide, which can damage health. Delhi has extremely high air pollution levels, with vehicles contributing around 75% of emissions. The number of vehicles in Delhi has grown rapidly without sufficient expansion of road infrastructure, leading to traffic jams and higher emissions. Various cities have implemented measures like congestion pricing, car-free days, and phasing out older vehicles to reduce vehicle emissions and improve air quality.

1. Role of Automobile in
air pollution

2. How does an automobile causes air pollution???
The following are the major pollutants from motor vehicles:
Carbon Monoxide: Emission of CO when the carbon in fuel doesn’t burn completely.When inhaled, CO
blocks oxygen from the brain, heart and other vital organs.
Hydrocarbon: A car exhaust emits hydrocarbon (a toxic compound).These pollutants react with nitrogen
oxides in the presence of sunlight to form ground level ozone (a primary ingredient in smog).Though
beneficial in the upper atmosphere, at the ground level this gas irritates the respiratory system causing
coughing and reduced lung capacity.
Nitrogen dioxides : N𝑶 𝟐 (created when heat in the engine forces nitrogen in the air to combine with oxygen)
causes lung irritation and weaken the body’s defense against respiratory infections such as pneumonia and
influenza.
Particulate matter : PM is a combination of organic material and inorganic substances. Dust, soil, acids,
metals and organic chemicals are some of the components of the PM. PM in the air contribute to
atmospheric haze and can damage people’s lungs.
Sulphur dioxide: Motor vehicles create Sulphur dioxide pollutant by burning sulfur-containing fuels,
especially diesel. It can react in the atmosphere to form fine particles and poses the largest health risk to
young children and asthmatics.

3. Reasons for vehicular pollution
Exhaust emission of toxic gases into the atmosphere.
Rapidly growing number of vehicles.
Absence of effective, efficient and well networked transport
system (especially in South Asia).
Use of very old vehicles.
Faulty traffic management systems and frequent jams.
Bad road conditions.
Poor fuel quality or use of adulterate fuel.
Automobiles with faulty engines/equipments or having bad
maintenance.
Violation of norms.

4. Studies shows that kids who grow up with cleaner air will have better lu
Air pollutants emitted from cars are believed to cause cancer, asthma, v
diseases, birth defects, eye irritation.
Transportation is the largest single source of air pollution in the US.
According to the Environmental Protection Agency (EPA), motor vehicl
75% of CO pollution in the US.The US has 30% of world’s automobiles,
about half of the world’s emission from cars.
The US was long considered the world’s biggest polluter in terms of car
other green house gases, but by 2008, the UN has reported that China h
top spot.

5. In case of India…..
WHO ranked Delhi as the most polluted city for air pollution in the
world in 2014 out of 1600 cities surveyed.
Government study findings also reveal that 3 quarters of the total air
pollution is contributed by vehicles.
Delhi has more vehicles than Mumbai, Kolkata and Chennai put
together.
According to a report of center for science and environment (CSE), air
pollution claims one life in Delhi per hour.
The two wheelers are the major contributors of vehicular air pollution
followed by four wheelers (car, jeep, taxi, etc.), trucks and buses in
decreasing order of magnitude.

6. Delhi is a typical example of air pollution by vehicles.
Number of vehicles versus road length:
Year Vehicles (in lakhs) Road length (in
KM)
1971 2.17 8380
1981 5.16 15490
1991 19.23 22487
1996 27.39 25948
2001 35.89 25948
2004 44.00 25948
2011 60.00 27000
The average travel time increases by over at least 12-15 minutes

7. Sources of air pollution in Delhi (in Percentage):
Year Vehicles Industry (includingTPS) Domestic
1970-71 23 56 21
1980-81 42 40 18
1990-91 64 29 7
2000-01 72 20 8

11. Anti-pollution measures in different cities:
Germany: Since 2010 in Berlin, an "ecological area" in the city center where only ve
enter.
Britain: A congestion toll implemented in London city center since 2003.
Greece: Since 1982, an alternating traffic system in Athens.
Hungary: An alternating traffic system was implemented in Budapest but in 2010 a n
with green, red or black stickers on cars.
Italy: An alternating traffic system in Rome since the 90s and restricted traffic areas
Portugal: There are some restricted traffic areas in the historic town centre of Lisbo
before 2000. Doesn't apply to residents.
Scandinavia: Congestion toll in Sweden; bike paths in Denmark; congestion toll and
China: The Chinese government has announced plans to take up to 6 million vehicle
standards off the roads by the end of the year, in a bid to reduce the country
Paris: Car free day, alternating traffic system.
Delhi: Bharat stage I, II, III, IV; Car free day; Alternating traffic system.
Newyork and other 7 states joined together in an initiative to put 3.3 million zero e
2025.