Tamil Nadu has seen a steady decline in air pollution in urban and rural areas between 2017 and 2022, a recent study has found.
The State has recorded a 22% reduction in fine particulate matter over the five-year period, observed Climate Trends, an environmental think-tank. Fine particulate matter is defined as particles that are 2.5 microns or less in diameter (PM 2.5).
The study was done through two methods - a satellite-based application by the Indian Institute of Technology, Delhi and the Central Pollution Control Board’s (CPCB) ground monitoring networks. In Tamil Nadu’s rural areas, the PM 2.5 level dropped from 46.6㎍/m3 (microgram per cubic metre) in 2017 to 32.9㎍/m3 in 2022. Whereas in urban places, the PM 2.5 levels were 42.7 ㎍/m3 in 2017 and 33.1 ㎍/m3 last year.
Among major cities, Chennai also saw a fall of PM 2.5 levels from 40.86㎍/m3 in 2017 to 28.90㎍/m3 in 2022, as per CPCB data.
“The analysis reflects the progress being made under the National Clean Air Programme (NCAP) with most States and Union Territories seeing a dip in their PM 2.5 levels over the last few years. When divided into NCAP and non-NCAP States, we see a more significant dip in States where NCAP is being implemented,” said Aarti Khosla, Director, Climate Trends.
Under the NCAP, only three cities in Tamil Nadu - Chennai, Madurai, and Tuticorin - have been categorised as non-attainment cities.
The study says while NCAP was designed to address high levels of air pollution in urban centres, there is an increase in pollution in rural areas too. “There is an urgent need to track pollution levels and develop policies for rural regions, as there is little difference in concentration levels between urban and rural areas,” it says.
The Tamil Nadu Pollution Control Board (TNPCB) is in the process of installing 25 new air quality monitoring stations, said R. Kannan, Member Secretary, TNPCB. The stations would be in district headquarters and towns where the population is more than one lakh, he said.
