The air quality in Pune is deteriorating fast, with pollution levels in the city crossing the ‘moderate’ mark of the Indian National Ambient Air Quality Standards, as per a recent study by a team of experts.
The study — titled Anthropogenic fine aerosols dominate over the Pune region, Southwest India — was jointly taken up by the Indian Institute of Tropical Meteorology (IITM), the department of geology at the Savitribai Phule Pune University and Stockholm University. It tracked levels of particulate matter (PM) 2.5 and 10 over Pune during 2016 and found that the highest contributor to the city’s deteriorating air quality was carbonaceous fine particles.
“Nearly 64 per cent of the city’s air pollution was contributed by finer particles, while the coarser particles amounted to 36 per cent. The major polluters were carbonaceous aerosols and secondary inorganic aerosols like sulfur-di-oxide, nitrites and ammonia,” stated the study published in Springer.
The causes of air pollution include factors like rapid expansion of the city, as the secondary contributors were particles from developing areas, emitted due to activities such as mechanical grinding, construction and quarrying. These particles are then carried over to remaining parts of the city in the form of dust. Non-exhaust vehicle emissions also contribute majorly to pollution.
“These elements together lead to the maximum hazard… also, concentration of sulphates, ammonium, organic compounds, elemental carbons, metals from multiple sources were… increasing over time,” stated the study.
Organic Carbon (OC) contains the largest carbon-containing fraction of ambient aerosols. This, in turn, aggravates when the combustion process remains incomplete and OC is emitted from biogenic sources, such as cars in a poor condition and vehicles that have not been maintained properly. “The pollution from OCs was the highest during winters, followed by summer and monsoon, when the concentration remained lowest due to the wind washaways,” noted the study.
Weather variations too had a significant role to play in the level of air pollution, as winter months saw the steepest fall in air quality.