According to the CPCB report, air quality in six urban areas of Odisha has been categorised as very poor on Sunday. Those places are Bhubaneswar, Cuttack, Balasore, Baripada, Keonjhar and Rairangpur.

The Air Quality Index (AQI) value for Balasore was 334 while it was 333 in Delhi on the day, the report stated. Balasore was followed by Cuttack with AQI of 320, Baripada 316, Keonjhar 314, Bhubanesar 311 and Rairangpur 308.

A senior official in the department of forest, environment and climate change said that the air quality in these places appeared to have deteriorated due to some temporary reasons, including construction and other activities.

It may be noted that prolonged exposure to very poor quality air may lead to respiratory problems and breathing discomfort among the people.

To get a perspective, AQI recorded in India’s financial capital Mumbai was 177.

Stubble burning, pollution from vehicles, construction and coal-fired power plants are the main contributing factors to polluted air in Delhi-NCR.

It’s between November and February that Delhi’s air quality is the worst. This time, AQI has hit record level well ahead of Diwali festivities.

Bloomberg quoted Anju Goel, an air quality research fellow at The Energy and Resources Institute, as saying that the poor AQI is due to a drop in temperature and slow wind speeds which affected the dispersal of pollution.

According to IQ Air data, Delhi recorded particulate matter (PM 2.5) of 296 micrograms per cubic meter of air, which is almost 20 times World Health Organization’s recommended level of 15.

At 4 pm on Monday, Delhi recorded an AQI of 313 in ‘very poor’ category, s per Central Pollution Control Board data.