Air Pollution: Impact, Causes & Solutions

Impact

Air pollution is a global problem. The impact of air pollution is so significant that almost 7 million people die per year according to the WHO (World Health Organization). It causes heart disease, skin cancer, lung cancer, lung cancer, pneumonia, cataract, etc. Apart from deaths, there are significant health costs which impact the economy as well. Like for example, air pollution costed the world $9.8 trillion or 10.3% of the global GDP in 2021 & also causes productivity loss. Air pollution also causes ecological impacts such as:

1. Ocean acidification: It is when too much CO2 gets absorbed by the ocean. When the CO2 enters the water, it combines with H2O forming carbonic acid. It affects marine life.
2. Global warming: It happens when greenhouse gases (GHGs) like CO2 and SO2 get into the atmosphere. When sunlight hits the earth, some of the heat gets absorbed into the ground while some gets reflected. If there are no greenhouse gases in the atmosphere the sunlight will go back into space. In case, greenhouse gases are present, then sunlight will get reflected back into earth causing more heat to get absorbed. This is called the greenhouse effect. It causes ecological impacts like rising sea levels when the extra heat warms up glaciers.
3. Depletion of the ozone layer: Back in the 1990s, fridges & ACs used to release CFCs. They used to go in the ozone layer. Which is a layer of ozone molecules (O3) which protects us from UV rays or ultraviolet rays. The problem is that CFCs destroys ozone molecules. Hence,  several countries started the Montreal protocol reducing CFC emissions drastically.  

Pollutants

A pollutant is a harmful gas present in the air that impacts our health and the environment. There are 2 types of pollutants:

• Primary pollutants: These are pollutants that come from a source. E.g.: CH4 (methane), CO2 (Carbon dioxide),SO2 (sulphur dioxide) etc. There are also pollutants called Synthetic Floriated Gases which are basically man-made gases. Ex: Chlorofluorocarbons, Hydrochlorofluorocarbons, Perfluorocarbons, Sulphur hexafluoride, nitrogen trifluoride, Hydrofluorocarbons.
• Secondary pollutants: They form when multiple primary pollutants combine. E.g.: Acid rain, smog, etc. Let us understand about secondary pollutants with an example. A factory releases sulphur trioxide (SO3) which goes up into the atmosphere and pollutes the air. This pollutant then combines with rainwater in clouds to form sulphuric acid or acid rain.

Sources

Pollutants come from various sources; they include natural & unnatural sources. The unnatural sources of air pollution includes indoor and outdoor. The outdoor environment includes major sources of air pollution such as vehicles, factories, and power plants.

While, the indoor sources include household appliances like stoves (which release water vapour which is a pollutant), cleaning products, fertilizers, etc. The natural sources of air pollution include dust storms, volcanic eruptions & wildfires. 

Trivia fact: Cows produce methane gas

How to address the problem

The government and the citizens of any country should work together to address the problem. Let’s start with what the government should do:

Government initiatives:

• Set emission limits: The government can set limits on how much air pollution a factory or vehicle can release. 
• Saving trees: The government should encourage planting more trees as they absorb pollutants and release oxygen.
• Promoting renewable energy: Power plants that generate electricity often rely on coal & fossil fuels which release pollutants. The government can switch to renewable energies like solar panels, windmills and hydroelectric dams as they do not release pollutants. 
• Controlling industrial emissions: Factories and power plants release smoke and harmful gases into the air. To reduce this, industries can use filters to clean the air before releasing it. 
• Promote electric vehicles (EVs):  The government can encourage usage of EVs through multiple ways:
• Reduce price for EVs 
• Increase EV charging points
• Increase price of diesel & petrol vehicles

What can citizens do? 

• Use public transport and carpool: Using public transport or carpool is better than using private transport. For instance, if 30 students travel by bus, it may release some CO₂, but if each student commute using their own transport, the total emissions will be much higher.
• Switch to EVs: EVs don't release CO2 making them a cleaner alternative to petrol & diesel vehicles.
• Avoid food waste: When discarded food decomposes in landfills, it releases methane, a harmful pollutant.
• Grow plants at home: Plants absorb carbon dioxide, nitrogen oxides, and particulate matter.
• Save electricity: This is an indirect process, as most electricity comes from power plants that emit CO₂. Therefore, turning off electronic devices when not in use helps reduce emissions.
Case study

Now that we have explored solutions, I have chosen Singapore as an example of a country that has taken significant steps to reduce air pollution. But before discussing Singapore’s efforts, let’s understand why I selected this country.
Below is a world map showing AQI (Air Quality Index) levels across different countries. The AQI is a measure of air pollution—the higher the number, the more polluted the air. As shown, India (along with China and Pakistan) have the highest pollution levels globally. By the way, the grey part is no data (other than Bhutan, Suriname, Panama, Guyana, Gabon, Comoros, Niue, and Madagascar).

Singapore has a higher population density than Hong Kong, meaning more people live within the same area. Typically, a higher population density leads to more pollution, so one might expect Singapore to have a higher AQI (Air Quality Index) than Hong Kong. However, this is not the case. 

Below is a comparison of Singapore vs. Hong Kong AQI levels from 2017 to 2024.

Both counties have taken a massive drop in AQI levels back in 2020 because of COVID-19. This was expected due to less vehicles on the road and reduced industrial emissions due to lockdown. Post 2020, the AQI levels in Singapore recorded back to 2017 levels. However, it recorded its lowest AQI levels in the last 7 years in 2024. This drastic drop to 11.4 AQI levels in 2024 was due to the following actions made by the Singapore government:  

• One Million Trees movement: Singapore started the 'OneMillionTrees' movement back in April of 2021 aiming to reach the target by 2030.
• Discourage petrol/diesel vehicles: Singapore has increased the price of diesel and petrol significantly over the years to divert people's attention to EVs.
• Encouraging EVs: One of the main reasons why people don't buy EVs is because, if they are less charging points. To combat this, Singapore plans to install almost 60,000 charging stations over the next decade. 
• Haze Pollution Act: Singapore introduced the Haze Pollution Act in 1997 to prevent haze (caused by forest fires) from Indonesia from polluting its air. Going forward, any foreign company in Indonesia that emits haze into Singapore will be heavily fined.
• Singapore Green act 2030: Singapore plans to reduce emissions by 2030 by focusing on solar energy, hydro power, and wind energy, instead of burning fossil fuels. 

Conclusion 

The primary aim of this blog is to raise awareness in our country about how we can learn from Singapore citizens to effectively reduce air pollution in India. Big changes start with small actions, so let’s commit to making a difference by planting trees, conserving energy, and choosing eco-friendly modes of transport like cycling or walking. Together, through these small but meaningful steps, we can create a cleaner and healthier future

*Source: https://www.weforum.org/stories/2024/08/healthcare-costs-digital-tech