This City Is The World's Most Polluted. Hint: It's Not Delhi

A small city on the Meghalaya-Assam border, nearly 2,000 kilometres away from Delhi, is the most polluted in the world, according to a report published by a global pollution watchdog.

Swiss air technology company IQAir's 2024 World Air Quality Report, which was released earlier this week, has said that residents of Byrnihat in Meghalaya breathe the most toxic air in the world. 

A small industrial hub that is home to several factories, including distilleries, iron and steel plants, Byrnihat recorded an annual average PM2.5 concentration of 128.2 micrograms per cubic metre, as against the World Health Organization's (WHO) limit of 5 micrograms per cubic metre. Byrnihat connects Shillong in Meghalaya to Guwahati in Assam.

PM2.5 refers to tiny particulate pollutants smaller than 2.5 microns, which can enter the lungs and bloodstream, leading to breathing problems, heart disease and even cancer. The sources include vehicle exhausts, industrial emissions and the burning of wood or crop waste.

According to the report, Byrnihat is followed by Delhi, Karaganda (Kazakhstan), Lahore (Pakistan) and Faridabad (Haryana, India) as the most polluted cities in the world.

Delhi's air quality has worsened and it remains the most polluted capital city globally, the report showed, with the annual average PM2.5 concentration rising from 102.4 micrograms per cubic metre in 2023 to 108.3 micrograms per cubic metre in 2024.

India ranked as the world's fifth most polluted nation last year, marking an improvement from its third rank in 2023, but 13 of the world's 20 most polluted cities were from the country.

Besides Byrnihat, Delhi and Faridabad, Punjab's Mullanpur, Loni, Gurugram, Ganganagar, Greater Noida, Bhiwadi, Muzaffarnagar, Hanumangarh and Noida are on the list. 

Overall, 35% of the Indian cities reported annual PM2.5 levels exceeding 10 times the WHO limit, the report said.

However, India saw a 7% decline in PM2.5 concentrations in 2024, averaging 50.6 micrograms per cubic metre, compared to 54.4 micrograms per cubic metre in 2023.

'Major Sources Likely On Assam Side'

Taking note of the report, Meghalaya Chief Minister Conrad Sangma on Thursday told the state assembly that the Meghalaya State Pollution Control Board (MSPCB) has found Byrnihat's air quality to be satisfactory, in comparison to the "poor to very poor" air quality recorded by a monitoring station installed in the Central Academy for State Forest Service, across the border in Assam.

"This indicates that the major sources of air pollution may be attributed to industrial and other activities on the Assam side," Mr Sangma said, pointing out that the areas in Byrnihat close to Assam have 20 "red category" (high pollution potential) industries while the Meghalaya part has five.

Speaking to reporters later in the day, Mr Sangma said he has written to his Assam counterpart, Himanta Biswa Sarma, on the issue and is awaiting a response. 

"I have written a letter to the Assam Chief Minister. I have not received any feedback (yet) but I will speak to him on the phone. It (report) is of great concern to all of us. I am very concerned and I am not very happy. I will definitely take personal interest in this. This is not something that I want our state to be labelled as, especially keeping in mind that tourism is a very important part of our state," he said. 

"I have mentioned in the statement that I laid in the House that being a border area, there are impacts from both sides. I am not saying there is more or less from our industries or from Assam industries but the numbers show that the red category and the industries are almost more on the Assam side than the Meghalaya side. But that does not mean that they are doing more or we are doing less," he added.

The Meghalaya Chief Minister said there is a need to work closely with Assam.

"So what's important is that we must come together, we must ensure that we take strict action, a joint program policy to monitor things together and ensure the overall air quality at Byrnihat improves," he said.

On Tuesday, Mr Sangma said polluters were identified in Meghalaya and closure notices were issued in the past one year.