Qualité de l’air à Nagpur

How bad are the levels of pollution in Nagpur?

Nagpur is a city in the Indian state of Maharashtra, with a population of just under 3 million people. It is known as one of the fastest growing cities in India, and as such it would have a number of air pollution problems associated with its population boom. Regarding the levels of pollution in the air taken in times past, Nagpur came in with an average PM2.5 reading of 47.2 μg/m³ over the year of 2019.

This reading would classify it as being ‘unhealthy for sensitive groups’, meaning that those with a predisposition towards being affected by pollution levels, such as the young, the elderly, the sick or immunocompromised may find themselves at risk breathing the air in Nagpur year-round, with some months displaying PM2.5 levels that far exceeded the yearly average.

PM2.5 refers to fine particulate matter that is approximately 3% the size of a human hair, being 2.5 micrometers or less in diameter. Nagpur also has high levels of PM10 in its air, with this being a fine particulate matter that is slightly larger in size, and whilst it presents health risks to those who inhale it, the microscopic size of PM2.5 makes it more detrimental to human health, and as such is one of the primary figures used in calculating the quality of a cities air.

Nagpur's 2019 average of 47.2 μg/m³ puts it in the position of 146^th most polluted city worldwide, and 50^th most polluted in India. With rankings like these to go by, it can be seen that the pollution levels in Nagpur are highly elevated, meaning that there would be large amounts of smoke, haze and other pollutants and fine particulate matters in the air, although there are several months of respite recorded, which will be discussed in further detail.

Have pollution levels improved in Nagpur?

Looking back at data taken over the last few years, it can be seen that Nagpur is making somewhat of an improvement, although it is still far away from the World Health Organizations (WHO) target goal for clean air of 0 to 10 μg/m³ of PM2.5 in the air.

Observing the numbers from 2017, the yearly average came in at 56.2 μg/m³, placing it in the ‘unhealthy’ bracket rating, which requires a reading of 55.5 to 150.4 μg/m³ to be classed as such. Whilst this is in the lower end of the unhealthy spectrum, it is still an undesirable number to be placed at, with many detrimental effects to health for those who breathe it.

In 2018 the reading was followed with 46.6 μg/m³, and then back to more current times 47.2 μg/m³ in 2019. This shows the whilst there was a slight fluctuation, the number was somewhat negligible (0.6 μg/m³) and as such, the air quality and pollution levels have improved over time in Nagpur.

What months see the worst air quality in Nagpur?

To refer to the data gathered over the year of 2019, there were a large number of differences between the months, with some marked disparity between the beginning, middle and end of the year. The month that came in with the absolute worst reading was February, with a PM2.5 reading of 122.3 μg/m³, placing it quite high up in the unhealthy bracket, and as such the air pollution would be distinctly harsh on all sections of the population, with preventative measures such as avoiding outdoor activities, or the wearing of high-quality particle filtering masks being necessary. Other months that followed closely were January, with a reading of 105.8 μg/m³, also putting it in the healthy category, and then November with 71.1 μg/m³.

March, April, May and December all came in with ‘moderate’ rankings, with readings ranging between 40.3 μg/m³ in December up to 54.8 μg/m³ in March. June through to October all saw the cleanest qualities of air in Nagpur, with September being the cleanest month of 2019 with a reading of 15.5 μg/m³, putting it only 5.5 μg/m³ over the WHO’s target goal for air quality.

How does Nagpur compare to other cities in India in terms of pollution levels?

When looking at the country as a whole, India comes in as one of the most polluted countries in the world, with city of Ghaziabad taking not only first place as the most polluted city in India as of 2019, but also the number one spot out of all cities ranked worldwide, coming in with a PM2.5 reading of 110.2 μg/m³, putting its yearly average high up in the unhealthy rating bracket.

To compare Nagpur with another city such as Delhi, in 2019 Delhi came in with a yearly average reading of 98.6 μg/m³, also putting it higher up in the unhealthy bracket. The city also saw PM2.5 levels soar as high as 200.7 μg/m³ in November, putting it into the elusive ‘very unhealthy’ bracket, which requires a very high reading of anywhere between 150.5 to 250.4 μg/m³ to be classed as such. The yearly average for Delhi, 98.6 μg/m³ was enough to place it 2^nd out of all cities in India, and 5^th place worldwide. This shows that whilst Nagpur suffers from its own tainted air issues, it is doing significantly better than other cities in India, with air quality levels that are improving over time.

What are the main causes of pollution in Nagpur?

There are numerous causes of pollution that all come together to further compound the overall levels of air quality, with sources such as vehicular emissions, construction site activities (in particular poorly maintained construction sites coming under fire in recent times due to the discovery of just how much fine particulate matter they can release into the air), as well as industrial pollution and smoke sources arising from domestic activities such as stove cooking with woods and other organic materials being burnt.

All these activities would release a myriad of pollutants into the air, with ones such as nitrogen dioxide (NO₂) being the most prominent, seen mainly in vehicular emissions, as well as being released from any other activities in which combustion takes place. Others would include sulfur dioxide (SO₂), carbon monoxide (CO) and ozone (O₃), as well as black carbon and volatile organic compounds (VOC’s) coming from the combustion of fossil fuels and organic matter.

Construction sites can leak large amounts of finely ground concrete or other industrial material dust, with microplastics and metals such as lead and mercury being of prominent concern. All these toxic forms of PM2.5 and PM10 are released into the atmosphere from a combination of the aforementioned activities, raising Nagpur's ambient pollution levels on a yearly basis.