Major Air Pollutants and Health Impact

pexels lio voo 12831608

Major Air Pollutants Behind Air Pollution: Know Your Facts

This Article is Updated on – 15/06/2023,  Originally posted on – 24/12/2020

Air pollution is a significant environmental concern that affects both the natural ecosystem and human health. The presence of various air pollutants in the atmosphere poses a serious threat to our well-being.

In this article, we will explore the major air pollutants and their health impacts. Understanding these pollutants and their sources can help us take necessary actions to mitigate their adverse effects.

Particulate Matter

Particulate matter (PM) refers to tiny particles suspended in the air. These particles can be solid or liquid and vary in size. PM is classified based on its diameter, with PM1.0, PM2.5, and PM10 being the most commonly measured sizes.

Particulate matter is one of the major air pollutant
Particulate matter is one of the major air pollutants on the list

PM2.5 refers to particles with a diameter of 2.5 micrometers or less.  PM10 refers to particles with a diameter of 10 micrometers or less.

Size RangeParticles with a diameter ≤ 10 µmParticles with a diameter ≤ 2.5 µmParticles with a diameter ≤ 1.0 µm
1. respiratory system
2. upper airways and lungs
1. Penetrate deep into the respiratory system

2. Reach alveoli in the lungs
1. Penetrate even deeper into the respiratory system

2. Capable of reaching the bloodstream
Health Impact1. Respiratory and cardiovascular issues,

coughing/ wheezing/ /shortness of breath
1 Respiratory and cardiovascular problems

2. May lead to
2.1 Lung cancer
2.2 Heart disease
Similar health effects as PM2.5 but with potentially higher risks
Sources1. Combustion processes

2. Dust sources

3. Construction activities
1. Combustion processes

2. Vehicle emissions

3. Industrial emissions

4. Wildfires
Similar sources as PM2.5, but with potential additional contributions from ultrafine particles
RegulationRegulated by environmental agencies in many countries to limit the permissible levelsRegulated by environmental agencies in many countries to limit the permissible levelsNot as widely regulated

Only in some important regions
MonitoringIn air quality monitoring stations In air quality monitoring stations Not as extensively monitored Only in some monitoring stations
Visibility1. Reduce visibility

2. Hazy conditions
1. Reduce visibility

2. Hazy conditions
1. Reduce visibility

2. Hazy conditions

But less noticeable
Comparison between PM10, PM2.5, and PM1.0


It’s important to note that while PM10, PM2.5, and PM1.0 are distinct categories based on size, they can often coexist in the atmosphere, and their health effects can overlap.

Monitoring and reducing the levels of all three particle sizes are crucial for protecting human health and improving air quality.

1. Main Sources

  • Industrial emissions
  • Vehicle exhaust
  • Construction activities
  • Combustion of fossil fuels
  • Forest fires

2. Health Impact

Particulate matter refers to tiny particles suspended in the air, including dust, soot, and smoke. These particles can vary in size, with smaller particles posing a greater health risk.

When inhaled, they can penetrate deep into the respiratory system and even enter the bloodstream.

Exposure to particulate matter is associated with a range of health problems. Including:

  • Respiratory issues such as
    • Coughing
    • Wheezing
    • Shortness of breath
  • Aggravation of asthma and other respiratory conditions
  • Increased risk of cardiovascular diseases.
  • Development of lung cancer
  • Premature death

particularly among vulnerable populations such as the elderly and individuals with pre-existing health conditions.

Carbon Monoxide

Carbon monoxide (CO) is a dangerous gas that is produced by the incomplete combustion of fossil fuels. It is released from sources like vehicle exhausts, industrial processes, and residential heating systems.

mathew macquarrie lzcKZlVPYaU unsplash
Smoking is one of the common reason leads to Carbon monoxide generation

1. Main Sources

  • Incomplete combustion of fossil fuels (e.g., vehicle emissions, industrial processes)
  • Tobacco smoke
  • Home heating systems

2. Health Impact

Carbon monoxide (CO) is a colorless and odorless gas produced by the incomplete burning of carbon-based fuels.

When inhaled, it binds to hemoglobin in the bloodstream, reducing its oxygen-carrying capacity. Prolonged exposure to high levels of carbon monoxide can lead to:

  • Headaches and dizziness
  • Nausea and vomiting
  • Impaired mental function and coordination
  • Cardiovascular effects, such as increased risk of heart attacks
  • Death in severe cases

It is crucial to ensure proper ventilation and take necessary precautions to prevent carbon monoxide poisoning.

Carbon Dioxide

Carbon dioxide (CO2) is a greenhouse gas naturally present in the atmosphere. However, human activities, such as burning fossil fuels and deforestation, have significantly increased their concentration.

pexels pixabay 37543
Carbon dioxide often notice combustion situations

CO2 is a major contributor to climate change and global warming.

1. Main Sources

  • Burning of fossil fuels (coal, oil, and natural gas)
  • Deforestation
  • Industrial processes

2. Health Impact

While carbon dioxide (CO2) is a natural component of the atmosphere and essential for plant photosynthesis, excessive concentrations due to human activities contribute to climate change.

However, the direct health impacts of carbon dioxide are not as significant as other pollutants. Health risks associated with high carbon dioxide levels indoors include:

  • Headaches
  • Drowsiness
  • Impaired cognitive function in extreme cases

The primary concern with increased carbon dioxide levels lies in its contribution to global warming and climate-related health consequences.

Sulfur Dioxides

Sulfur dioxide (SO2) is a gas produced primarily by burning fossil fuels that contain sulfur. It is released from power plants, industrial processes, and residential heating systems.

marc szeglat IzoQu5vH47o unsplash
Volcano eruptions release mega levels of SO2 into the atmosphere

SO2 can also be generated by volcanic eruptions like natural phenomena.

1. Main Sources

  • Burning of fossil fuels, particularly coal, and oil
  • Industrial processes, such as smelting and refining
  • Volcanic eruptions

2. Health Impact

Sulfur dioxide (SO2) is a gas released during the combustion of sulfur-containing fuels. It reacts with other compounds in the atmosphere to form fine particulate matter and acid rain.

Short-term exposure to high levels of sulfur dioxide can lead to:

  • Irritation of the respiratory system
  • Aggravation of asthma and other respiratory conditions
  • Respiratory symptoms like coughing and wheezing

Individuals with pre-existing respiratory issues are more susceptible to the adverse effects of sulfur dioxide.

Nitrogen Oxides

Nitrogen oxides (NOx) are a group of gases that include,

  • Nitric oxide (NO)
  • Nitrogen dioxide (NO2).
michael d jSADgWPmKDU unsplash
The higher energy of thunderstorms forms NOX after reacting with N2 gas in the atmosphere

These gases are produced mainly by human activities. Additionally, natural sources like lightning and microbial activity in soils also contribute to NOx emissions.

CharacteristicNitric Oxide (NO)Nitrogen Dioxide (NO2)
Chemical FormulaNONO2
CompositionOne nitrogen (N) atom + one oxygen (O) atomOne nitrogen (N) atom + two oxygen (O) atoms
Color and OdorColorless gas
slightly sweet odor
Brownish gas
pungent, sharp, and choking odor
FormationCombustion processes, such as burning fossil fuels at high temperaturesOxidation of NO or the reaction of nitrogen oxides with ozone
Atmospheric PresenceIn low concentrations in the atmosphereIn urban and industrial areas with higher pollution levels
Health Effects1. Low toxicity

2. High concentrations can cause respiratory irritation

3. Contribute to the formation of smog and acid rain
1. More toxic than NO
2. Cause respiratory issues, eye irritation, and lung damage

3. Major component of air pollution
Environmental ImpactReact with oxygen and other compounds to form nitrogen oxides (NOx), which contribute to air pollution and environmental problemsContributes directly to air pollution, plays a role in the formation of photochemical smog and acid rain
Chemical ReactivityRelatively reactive

Readily react with oxygen to form NO2 or combine with other atmospheric components
Highly reactive

React with various substances, including ozone, hydrocarbons, and particulate matter
Role in Nitrogen CycleAn intermediate product in the conversion of ammonia (NH3) to nitrate (NO3) in the process of nitrogenNO2 is not directly involved in the nitrogen cycle
Characteristic comparison between NO2 vs NO

1. Main Sources

  • Vehicle emissions
  • Power plants
  • Industrial processes
  • Agricultural activities

2. Health Impact

Nitrogen oxides (NOx) are produced from the combustion of fossil fuels. They contribute to the formation of smog and acid rain. Exposure to nitrogen oxides can have several health implications, including:

  • Respiratory problems such as inflammation of the airways
  • Increased risk of respiratory infections
  • Aggravation of asthma symptoms
  • Reduced lung function
  • Greater susceptibility to respiratory illnesses in children

Efforts to reduce nitrogen oxide emissions can significantly improve air quality and mitigate health risks.


Ozone (O3) is a gas that exists in the Earth’s upper atmosphere (stratosphere) and the lower atmosphere (troposphere).

lizgrin f lsQZfwPlKos unsplash
Ground-level ozone is a major component of smog

Ozone in the stratosphere protects us from harmful ultraviolet radiation. But at ground level, it is considered a pollutant and a major component of smog.

1. Main Sources

  • Chemical reactions between nitrogen oxides and volatile organic compounds (VOCs) in the presence of sunlight
  •  Industrial emissions
  • Vehicle exhaust

2. Health Impact

While ozone (O3) plays a beneficial role in the upper atmosphere, at ground level, it is a harmful air pollutant. Ozone can cause a range of health issues, particularly on hot and sunny days. Its adverse effects include:

  •  Respiratory irritation
  • Coughing and throat irritation
  • Aggravation of asthma and other respiratory conditions
  • Reduced lung function
  • Increased susceptibility to respiratory infections

Individuals with respiratory conditions, children, and the elderly are more vulnerable to the health impacts of ozone.

Water Vapor

andreas strandman TzPpj2ww gI unsplash
Water Vapour also leads to air pollution as a gaseous components

Water vapor is the gaseous form of water present in the Earth’s atmosphere. While water vapor itself is not considered a pollutant, excessive levels of humidity can contribute to the formation of other pollutants and impact human health indirectly.

1. Main Sources

  • Natural processes such as evaporation and transpiration
  • Human activities indirectly contribute to increased water vapor through climate change

2. Health Impact

Water vapor is the gaseous form of water. It is a natural component of the atmosphere. While it is not considered a pollutant itself, its presence and levels contribute to climate patterns and weather conditions.

 Changes in water vapor concentration due to climate change. This can indirectly impact human health by influencing extreme weather events. Such as heatwaves, storms, and floods.

These events can lead to injuries, displacement, and various health risks.


Major air pollutants have significant impacts on human health and the environment.

These above-mentioned air pollutants play a major role in air pollution. And they contribute to various respiratory and cardiovascular problems.

It is crucial to raise awareness about these pollutants. Also, we should take steps to reduce their emissions for the well-being of individuals and the planet as a whole.



Q: How can I protect myself from air pollutants?

A: To protect yourself from air pollutants, you can take several measures:

  • Stay informed about air quality levels in your area and limit outdoor activities on days with poor air quality
  • Use air purifiers or filters in your home to reduce indoor air pollution
  •  Maintain good ventilation in your living spaces
  • Use public transportation, carpool, or choose eco-friendly modes of transportation to reduce emissions
  • Support policies and initiatives aimed at reducing air pollution

Q: Are children more vulnerable to the health effects of air pollution?

A: Yes, children are particularly vulnerable to the health effects of air pollution. Their lungs are still developing.

Also, they breathe in more air relative to their body weight compared to adults. Exposure to air pollutants during childhood can have long-lasting effects. Both on respiratory health and overall well-being.

Q: How can we reduce air pollution?

A: Reducing air pollution requires collective efforts. Some effective strategies include:

  • Transitioning to cleaner and renewable sources of energy
  • Promoting energy efficiency in industries, transportation, and households
  • Encouraging the use of public transportation and active modes of commuting
  • Implementing stricter emissions standards for vehicles and industrial processes
  • Planting trees and creating green spaces to improve air quality and provide natural air filtration.

Q: Can air pollution affect the climate?

A: Yes, When we talk about air pollution, greenhouse gases like carbon dioxide, directly can contribute to climate change.

The release of these gases into the atmosphere traps heat. They lead to global warming and changes in weather patterns.

Addressing air pollution is essential not only for human health.  But also for mitigating the impacts of climate change.

Q: What is the role of individuals in reducing air pollution?

A: Individuals can contribute to reducing air pollution by making conscious choices, such as:

  • Conserving energy and using energy-efficient appliances.
  • Reducing waste and recycling.
  • Using public transportation or carpooling.
  • Planting trees and creating green spaces.
  • Supporting clean energy initiatives.
  • Educating others about the importance of air quality and pollution reduction.

Read Us More. Know Your Facts

Follow Us on FacebookInstagramTwitterPinterest, and LinkedIn

Air Purifiers - Breathe With NEED

Vornado Air Purifier QUBE50 for Home

Learn More

Air Purifiers - Breathe With NEED

VEWIOR Air Purifier, Home Air purifier

Learn More

Air Purifiers - Breathe With NEED

Rabbit Air Purifier A3 SPA-1000N Ultra Quiet

Learn More

*This page contains affiliate links, and We earn commissions from qualifying purchases through these links. Please review our Affiliate Disclaimer for details.