Air pollution is one such form that refers to the contamination of the air,
irrespective of indoors or outside. A physical, biological or chemical alteration
to the air in the atmosphere can be termed as pollution. It occurs when any
harmful gases, dust, smoke enters into the atmosphere and makes it difficult for
plants, animals and humans to survive as the air becomes dirty.
Air pollution is the world’s deadliest environmental problem. It kills 7 million
people each year, or one in eight deaths globally. 4.3 million of these deaths
are due to 2.8 billion people in the developing world who cook and keep warm
inside their homes, by burning dung, firewood and coal – filling their living
spaces with smoke and pollutants. Indoor air pollution from cooking and heating
with open fires is equivalent to smoking two packets of cigarettes a day.
Providing 50% of these 2.8 billion people with improved cooking stoves – which
dispels smoke outside through chimneys and vents, are one effective solution.
The stoves are cheap and provide numerous benefits in terms of time, fuel and
importantly health. It will save almost half a million lives each year, and avoid
2.5 billion disease days.
Indoor air pollution and poor urban air quality are listed as two of the worlds
worst toxic pollution problems in the 2008 Blacksmith Institute World’s Worst
Polluted Places report. According to the 2014 WHO report, air pollution in 2012
caused the deaths of around 7 million people worldwide, an estimate roughly
matched by the International Energy Agency.
Causes of Air Pollution
An air pollutant is a substance in the air that can have adverse effects on
humans and the ecosystem. The substance can be solid particles, liquid
droplets, or gases. Some of causes are:
   Air pollution is caused when air in the atmosphere is filled with particulate
    matter.
   The largest source air of pollution in cities is from vehicle exhaust fumes.
   Carbon monoxide is the largest air pollutant in the United States, and its
    number one source is from vehicle exhausts.
   Carbon monoxide is a poisonous, odourless, colourless gas that is
    formed when burning fossil fuels such as coal, petroleum and natural gas.
   Filters that are not changed regularly in your air conditioning units will
    accumulate dirt and cause the spread of pollutants in the air you breathe
    inside your home.
   Chemicals and toxic pollutants likes sulphur dioxide, nitrogen oxides and
    carbon dioxide react with water molecules in the atmosphere to produce
    acid rain. These pollutants come from factories, automobiles and any
    industrial or manufacturing plants.
   Another source of air pollution is from dust and dirt that goes airborne due
    to every day labour in the agricultural and construction industry. Dust is
    lifted from tractors working on fields, and from land clearing and general
    demolition in the construction industry.
   Using household chemicals without adequate ventilation is a major
    source of indoor air pollution.
   Volcanoes, dust storms, and forest fires are causes of natural air
    pollution.
      Mining is a process wherein minerals below the earth are extracted using
       large equipment’s. During the process dust and chemicals are released
       in the air causing massive air pollution. This is one of the reasons which
       is responsible for the deteriorating health conditions of workers and
       nearby residents.
Effects of Air Pollution
Air pollution is a significant risk factor for a number of pollution-related diseases
and health conditions including respiratory infections, heart disease, COPD,
stroke and lung cancer. Children in areas exposed to air pollutants are said to
commonly suffer from pneumonia and asthma.
Air pollution costs the world economy $5 trillion per year as a result of
productivity losses and degraded quality of life, according to a joint study by the
World Bank and the Institute for Health Metrics and Evaluation (IHME) at the
University of Washington, These productivity losses are caused by deaths due
to diseases caused by air pollution. Some of other effects are:
      Contaminated air reduces the body’s defences and decreases the body’s
       capacity to fight other infections in the respiratory system.
      Frequent exposure to polluted air increases the risk of cardiovascular
       disease. Breathing air that is filled with fine particulate matter can induce
    hardening of the arteries, triggering cardiac arrhythmia or even a heart
    attack.
   People who exercise outdoors are susceptible to the adverse effects of
    air pollution because it involves deeper and faster breathing.
   Acid rain contains hydrogen ions, which can damage trees, crops, harm
    marine animals and induce corrosion in metals.
   Smog causes harmful health effects in humans and animals. Studies
    have shown signs of black lung disease in dolphins of due to high
    concentrations of carbon particles in the air.
   People afflicted with heart disease, children and older people are more
    sensitive to air pollution.