NO₂ Pollution Increased Dramatically in India’s Major Cities in 2021

NO2 is an important pollutant to track because exposure to high concentrations can lead to respiratory problems in humans. So did India’s nitrogen dioxide levels improve in 2021? How did COVID-19 lockdown affect NO2 levels in India?

Why NO₂ is Dangerous

NO₂ can transform into ground-level ozone, which poses a major risk to human respiratory systems. The American Lung Association has stated NO₂ causes a range of harmful effects on the lungs, and people who are suffering from lung cancer face greater threat from NO₂. New research found air pollution linked with other health problems including cardiovascular, low birth weight & premature death.

NO2 Levels in India Increased in Every Major City

According to the latest Greenpeace report, NO2 pollution levels have increased in every major Indian city in 2021 compared to 2020. Smart Air analyzed NO2 quality data for eight major Indian cities: Delhi, Mumbai, Kolkata, Chennai, Hyderabad, Bengaluru, Lucknow, and Jaipur.

Next, we take a deeper dive into the NO2 levels of each major Indian city analyzed starting from the largest to smallest increases.

Delhi’s NO2 Levels Increased by 126%

Indian capital city Delhi famous for its air pollution saw an over 100% increase in NO₂ level in 2021 compared to 2020. This is not surprising as vehicular emissions are the largest contributor to air pollution in Delhi. Cars, trucks, autos, two-wheelers, and road traffic contribute over 38% of Delhi’s overall particulate matter emissions.

Chennai’s NO2 Levels Increased by 94%

Even though Chennai air quality is known to be better than air quality in most other Indian major cities; Chennai saw an 94% increase in NO₂ levels in 2021 compared to 2020.

Bangalore’s NO2 Levels Increased by 90%

The southern city of Bangalore saw a 90% increase in NO₂ level in 2021 compared to 2020.

Hyderabad’s NO2 Levels Increased by 69%

NO2 levels in Hyderabad increased by 69% in 2021, making Hyderabad ranked second highest in NO2 levels amongst Indian’s largest cities.

Mumbai’s NO2 Levels Increased by 52%

Mumbai’s NO2 levels increased by 52% from 2020 to 2021. PM2.5 air quality in Mumbai also has worsened recently.

Jaipur’s NO2 Levels Increased by 47%

Jaipur saw an increase of 47% in NO2 levels from 2020 to 2021.

Lucknow’s NO2 Levels Increased by 32%

Lucknow saw an increase of 32% in NO2 levels from 2020 to 2021.

Kolkata’s NO2 Levels Increased by 11%

Kolkata saw a slight increase of just 11% though it ranked third in NO₂ level 2021 for India’s major cities.

How Did COVID-19 Lockdowns Affect India NO₂ Pollution Levels?

After the initial lockdown, pollution in many Indian cities improved.

But the second lockdown imposed in 2021 was not as strict as the first because several transportation and industrial activities were still operational. This led to an increase in NO₂ levels for all Indian cities in 2021 compared to 2020.

Bottom Line: NO₂ pollution has increased dramatically in eight major Indian cities

NO₂ pollution has increased drastically in all of Indian major cities, with Delhi leading the increase with 2021 levels 126% higher than in 2020.

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How I Protect Myself

Because the health consequences of India’s severe pollution are devastating, protection is vital. Wearing a mask not only helps protect against air pollution but also slows the spread of coronavirus. Also using air purifiers in your home has been shown to have positive effects on blood pressure, inflammation, and immune response. An air purifier with a HEPA filter can remove all PM2.5 from the air, and an additional carbon filter can remove the NO₂ and other dangerous gases from the air.

Smart Air is a certified B Corp committed to combating the myths big companies use to inflate the price of clean air.

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