New Delhi: After improving slightly Delhi air quality degraded and turned 'severe' again on Saturday evening due to an increase in pollution from stubble burning and unfavourable weather conditions.

What is worse is that experts are saying air quality will degrade further as farm fires keep on raging.

Hindustan Times reported that an official at Punjab’s pollution control board said that at least 10,000 instances of farm fires were recorded, since Wednesday.

The concentration of PM2.5 particles in the air is increased by farm fires and emissions from firecrackers and these particles pose a major health risk as they can enter the bloodstream after being inhaled.

The official also said this current rate, the total count of farm fires might cross last year’s numbers.

Another major concern that contributed to the severity of Delhi’s pollution is the systematic chopping down of trees.

Over 1.12 lakh trees were axed over in the past 13 years to make space for infrastructural and real estate projects.

India Today, citing Delhi government data, reported that 15,276 trees were removed by the Delhi Metro Rail Corporation (DMRC), 15,762 trees were axed over by the Public Works Department (PWD) and another 2,786 were cut by Rites Ltd. for the Bus Rapid Transit (BRT) corridor from Ambedkar Nagar to Moolchand in South Delhi.

On Saturday, the PM 2.5 (particles in the air with a diameter of less than 2.5 micrometres) level was recorded at 261 while the PM10 (particles in the air with a diameter of less than 10 micrometres) was recorded at 416 in Delhi, according to data by the Central Pollution Control Board (CPCB).

Twenty areas in Delhi recorded severe air quality while 15 areas recorded very poor air quality, according to the CPCB.

Ghaziabad, Faridabad and Greater Noida recorded severe air quality while Noida and Gurgaon recorded very poor air quality, according to the CPCB.

The air quality in Delhi has been severe for the past two days with the highest pollution level of the year recorded a day after Diwali on Thursday at an AQI of 642.

Meanwhile, the Environment Pollution Control Authority has asked the authorities to extend the ban on construction activities, industries using coal and biomass and entry of trucks till November 12 due to the deteriorated air quality in the national capital.

With inputs from PTI