RC Parida & HS Fatesingh

Air pollution has emerged as a major threat to mankind as a whole, and India has earned a dubious distinction of being the third most polluted country after Bangladesh and Pakistan, with 13 of its cities coming under the 20 worst affected in the world, according to the World Air Quality Report 2024, published in March 2025 by the Swiss Company IQAir. It is playing havoc with the health and longevity of the people, adversely affecting human resources and the economy. 

Of all the major air pollutants, the Particulate Matter (PMs) are playing a pivotal role in reducing the air quality, measured by a scale called the Air Quality Index or AQI. Therefore, tentatively, the AQI is determined from the concentration of the air at a place. Those have been divided into two categories, PM2.5 and PM10, depending on the sizes of their particles. In case of the former, those have diameters less than 2.5 micrometres, while for the latter, between 2.5 and 10 micrometres. 

The sources of particulate matter can either be natural or man-made. Those are respectively produced from natural events like wildfire, volcanic eruption, dust storms, etc., and human activities that include industrial emissions, vehicle exhaust fumes, domestic use of fossil fuels, construction activities, agriculture, etc…read more on NOPR