Delhi gasps for breath as toxic haze engulfs city; people face eye irritation, respiratory issues

New Delhi, Oct 30 (PTI) A blanket of haze shrouded the national capital on Thursday, with people complaining of eye irritation and cough, as air quality stood close to the "severe" level. Experts blamed meteorological conditions that trap pollutants near the surface for the rise in the pollution level.

The India Meteorological Department (IMD) said the haze is expected to persist during early morning and late evening hours through the week, as particulate matter continues to accumulate near ground level.

Delhi, which has been witnessing a fall in air quality since Diwali, recorded 'very poor' air quality with an AQI of 373, a sharp rise from 279 a day earlier. Smog significantly reduced visibility, with the Central Pollution Control Board (CPCB) recording PM 2.5 levels at 184.4 and PM 10 at 301.9.

Out of the 38 monitoring stations in the city, 37 recorded "very poor" air quality with readings above 300, the CPCB said. Vivek Vihar (426), Anand Vihar (415), Ashok Vihar (414), Bawana (411), Wazirpur (419) and Sonia Vihar (406) saw "severe" category air quality.

In the NCR region, Noida recorded an AQI of 372, Ghaziabad 364, Greater Noida 330, Gurugram 248 and Faridabad 166.

An AQI between zero and 50 is considered 'good', 51 to 100 'satisfactory', 101 to 200 'moderate', 201 to 300 'poor', 301 to 400 'very poor' and 401 to 500 'severe', according to the CPCB classification.

Experts said the yellowish smoke enveloping the city is smog -- a mixture of fog and pollutants that reduces visibility and poses serious health risks, especially for vulnerable groups.

According to the IMD's Decision Support System, Delhi's transport sector contributed around 15.9 per cent to PM2.5 levels, while stubble burning accounted for about 6 per cent and emissions from Delhi residents around 4 per cent.

Neighbouring cities such as Ghaziabad and Noida contributed 10 and 6 per cent to the pollution, respectively, while other regional sources together added over 22 per cent.

Satellite data for October 29 detected 283 farm fire incidents in Punjab and 10 in Haryana, indicating a continued impact of stubble burning on Delhi's worsening air quality.

Weather experts attributed the rise in pollution to meteorological conditions that trap pollutants near the surface.

"The dip in minimum temperature helps in forming a layer of haze as pollution settles in the lower atmosphere," said Mahesh Palawat, the vice-president of meteorology and climate change at Skymet Weather.

According to him, winds blowing from the east at 2 kmph to 5 kmph and a rise in humidity worsened the air quality on Thursday. Medium and low clouds have obscured the sky, and isolated light rain was recorded in Noida and Faridabad, he said.

Sunil Dahiya, the founder and lead analyst at Envirocatalyst, said, "Decreasing wind speed and overcast conditions are reducing pollutant dispersion. To see any significant improvement, emission sources across the power, industry, transport, waste and construction sectors in Delhi-NCR need to be targeted." Dipankar Saha, former additional director and the head of air laboratory at CPCB, said, "Poor air quality is typical for this season, caused by air stagnation due to low wind speed and a shallow thermal boundary layer." "The Indo-Gangetic Plain is witnessing low wind speed, which hampers ventilation. However, this doesn't mean emission control can be ignored -- reducing emissions will still lessen exposure to harmful pollutants," he said.

The Air Quality Early Warning System for Delhi reported that the city's ventilation index -- a measure of the atmosphere's ability to disperse pollutants -- remained below the favourable level of 6,000 m²/s.

Weak winds under 10 kmph and high humidity prevented pollutants from dispersing, resulting in a hazy sky.

At 7.30 am, the IMD recorded a visibility of 1,000 metres at Palam and 800 metres at Safdarjung, both reporting calm wind conditions.

Doctors at city hospitals say they have been receiving a rising number of patients with complaints of cough, breathlessness, chest tightness and nasal congestion.

According to Dr Vivek Nangia, the vice-chairman and head of pulmonology at the Max Super Speciality Hospital in Saket, all the patients who visited the facility on Thursday were complaining that their symptoms had worsened since Diwali.

"One thing we are clearly noticing is that whoever is coming now is saying that ever since the AQI levels have gone up, their cough, breathlessness, chest tightness, and nasal congestion have all significantly worsened," he added.

Dr Medha, a paediatrician at the Madhukar Rainbow Children's Hospital, said, "Many are also dealing with eye irritation, sore throats and disturbed sleep due to poor air quality." Delhi's maximum temperature settled at 27 degrees Celsius, two notches below normal, while the minimum stood at 20.1 degrees Celsius -- four notches above the seasonal average. Humidity at 5.30 pm was recorded at 75 per cent.

The weather department has forecast shallow fog on Friday, with the maximum and minimum temperatures expected to hover around 30 and 18 degrees Celsius, respectively. PTI SHB SHB NSD NSD