As air monitoring agencies predicted similar situation for some more days, health problems are likely to be aggravated.
Pulmonologists in Delhi have warned people, especially those with lung diseases, to stay indoors. Dr. Vikas Maurya, Pulmonologist at BLK hospital, said prolonged exposure to highly toxic air can cause cardiac arrest and lung cancer.
"The current air quality is going to impact those with respiratory problems, especially asthmatic patients, negatively. However, it also creates problems for those facing cardiac and nervous system problems. The long-term exposure to pollutants in the air increases chances of lung cancer and heart attack," said Maurya.
"Pollutants can affect foetus growth," he cautioned pregnant women.
He advised use of mask as a necessary precautionary measure when going out in open air.
"One should avoid going outdoors. Otherwise, one should use mask like N-95 or N-99. Parents must take care of children as toxic air can affect lung growth in them," said the pulmonologist.
He asked the government to take proper measures to reduce pollution. "It is the government's job to take necessary measures. In addition, people should also play pro-active role," Maurya said.
A Jammu resident, Amit Gupta, who works in Delhi, found the air quality horrible when he returned to the city after Diwali vacations.
"When I got down from the train, I saw fog everywhere, However, when I started feeling irritation in my eyes I came to know that it was smog. The situation is horrible here. I should have extended my stay in Jammu," said Gupta.
While Air Quality Index in cities like Mumbai, Chennai and Bengaluru has shown considerable improvement, it is still 'severe' for Delhi and NCR. The reasons given by the air monitoring agencies are adverse weather conditions. such as low wind speed coupled with drop in temperature. and high humidity, which has blocked dispersal of pollutants.
System of Air Quality and Weather Forecasting and Research (SAFAR) under Ministry of Earth Sciences, showed levels of PM (particulate matter) 2.5 and PM 10 exceeding 500 at most locations early on Thursday morning.
The Central Pollution Control Board (CPCB) data also showed increase in toxicity.
Dipankar Saha, a scientist working with CPCB, said the high level of pollution is due to adverse weather conditions.
"While we should stop all activities which contribute to pollution, there is no need to create panic. We need good weather conditions after which air quality will improve," he said.