Air pollution not only causes physiological problems, but
also psychological, sociological, and economical distress.
Diseases cause by air pollution impact people enormously.
People visit doctors more often, parents get worried about their
children’s' health and future, governments spend more money
on air pollution research, and so on. The New York Times
Magazine published an interesting article named “Holding
Your Breath in India.” It told the story of an American couple
who moved to Delhi, one of the most polluted cities. This
caused one of their sons to develop asthma. They found out
that their son also lost half of his lung function. So he had to
be treated with steroid therapy all the time while staying in
Delhi. This brought tremendous stress to the family, especially
when their son's symptoms worsened and he was hospitalized
(Harris, 2015).
Most air pollution is caused by vehicle emissions. As
populations increase each year and technology becomes more
accessible, the number of cars tends to go up. In 1970, the total
number of vehicles in the world was about 250 million. Now,
around one billion vehicles are on the road worldwide. It is
expected that by 2050, the number might reach two and a half
billion cars. (Discovery news, 2011.) Each car causes more