Air Pollution

Air pollution surrounds us mostly out of sight, but it is very damaging. From car exhausts to fires in rubbish tips, the reasons are various and the consequences broad. 

This article is intended to provide insights about what air pollution actually is, why it occurs, and how it affects our health and environment. Above all, it also indicates what we can do to counteract it together.

Table of Contents

• What is Air Pollution
• Types of Air Pollutants
• Causes of Air Pollution
• Air Pollution Effects
• How Can We Cut Air Pollution

What is Air Pollution?

Air pollution happens when foreign or toxic materials mix with the air that we breathe. They may come from car exhaust, factory smoke, or even natural events like volcanic eruptions. 

Over time, these pollutants destroy our health, ruin nature, and upset the equilibrium of our climate.

Types of Air Pollutants

Air pollutants are broadly classified into two categories depending on whether they are emitted directly into the atmosphere or are produced later through chemical processes.

Primary Pollutants

These are the atmospheric pollutants that are emitted directly into the air from a source. These are common in city traffic, factory chimneys, and even household activities. Examples include:

• Carbon Monoxide (CO): Produced from cars and bikes. It’s hazardous because it blocks oxygen from reaching your body’s cells and affects the human body.
  
  
• Sulphur Dioxide (SO₂): Mainly present in smoke from coal-burning industries. It can cause coughing and lung irritation.
  
  
• Nitrogen Oxides (NO and NO₂): Produced by motor vehicles and power plants. They are responsible for smog and acid rain.
  
  
• Particulate Matter (PM2.5 and PM10): Particles of fine dust, soot, or smoke suspended in the air. They can easily enter your lungs and cause breathing problems.
  
  
• Volatile Organic Compounds (VOCs): From painting, petrol, and some household cleaning products, which cause indoor and outdoor pollution.
  
  

Secondary Pollutants

These pollutants do not release directly. They are formed when primary pollutants react with the sun, water vapour, or other air chemicals. Major examples are:

• Ground-Level Ozone (O₃): This ozone is dangerous (in contrast to the safe ozone layer) and is produced when VOCs and nitrogen oxides react in sunlight. It induces chest pain and aggravates asthma.
  
  
• Photochemical Smog: A dense haze that can be observed in urban areas, particularly during the winter. It occurs when sunlight interacts with car exhaust and industrial emissions.
  
  
• Acid Rain: Created when SO₂ and NOx combine with water vapours in the atmosphere to produce acids, which are washed down with rain. It can kill crops, erode soil, and damage buildings.
  
  
• PAN (Peroxyacetyl Nitrate): A smog chemical that irritates eyes and kills plants.
  
  

Causes of Air Pollution

The major causes of air pollution are mentioned below : 

1. Transport and Traffic
   Vehicle exhaust is among the greatest causes of urban air pollution. The more there are vehicles on the road, the greater the number of pollutants emitted.
   
   
2. Industries and Factories
   Chemical, cement, metal, or plastic-producing factories emit smoke and toxic gases into the atmosphere, particularly when they use coal or oil for burning.
   
   
3. Burning of Fuels
   Coal, wood, and other fuels burned for cooking, space heating, or making electricity emit a combination of poisonous gases and smoke.
   
   
4. Demolition and Construction
   Building sites and demolition dust deposits small particulate matter into the air, which can be easily breathed in.
   
   
5. Garbage Burning
   Garbage is still openly burned in many places - sending toxic fumes into the air we all share.
   
   
6. Farming Methods
   Burning residues of crops, spraying pesticides, and applying chemical fertilisers also put pollutants into the air.
   
   
7. Natural Sources
   Volcanic eruptions, forest fires, and dust storms also contaminate the air, though these are less common.

Air Pollution Effects 

Air pollution doesn't only dirty the air as it harms our lives more than we know:

• On Health

Exposure to polluted air may cause cough, sore throat, chest tightness, asthma, and even heart disease or cancer in extreme cases. Children and the elderly are most vulnerable.

• On Nature

Pollutants inhibit plant growth, destroy leaves, and kill animals that inhale the same air. Acid rain alters the quality of soil and pollutes rivers and lakes.

• On Buildings

Ever seen blackened buildings or statues? That's because pollutants such as sulphur dioxide combine with rain and wear out stone in the long run.

• On Climate

Air pollution adds to the concentration of greenhouse gases, warming the atmosphere. It results in global warming, melting glaciers, sea-level rise, and extreme climate events.