"No Indian today is a non-smoker," said Dr Arvind Kumar, a lung cancer surgeon at Sir Ganga Ram Hospital. "Ours is the only country with infant smokers - every minute 34 infants in India are born, and essentially handed a cigarette."
Over the last week, the amount of fine particulate matter or PM2.5 levels has been recorded at 151. This is equivalent to smoking 20 cigarettes a day by each resident. PM2.5 are tiny particles in the air that also reduce visibility and cause the air to appear hazy when levels are elevated.
Atul Kumar Jain, a shopkeeper in Sadar Bazar, was diagnosed with lung cancer at 39. Half his left lung had to be removed.
"I have never touched a cigarette in my life," said Mr Jain.
Dr Kumar further said that earlier the lungs of non-smokers used to be pink, but now even they are usually black or have black spots.
"20 years ago, all lungs were pink, only smokers' lungs were black. Now all the lungs I operate on are black or have black spots, and those toxins once deposited can never be cleaned out," he said.
From a negligible number of non-smokers with lung cancer, Dr Kumar says that 30 to 40 percent of his patients now are non-smokers. They are also much younger that the average lung cancer patient in other countries, in their 30s and 40s.
Those who spend time indoors are not safe either. 59 year old Poonam Kalra spends her days at home, but a tumour was found in her lungs. A third of her right lung was removed six months ago.
"They asked me tell us truthfully do you smoke, and it hurt me so much," she said. "My husband, my children, no one smokes, we haven't even burst crackers in 7-8 years, yet this tragedy befell me."
She blames pollution, and is now worried for her four month old grandson. "Every time one of my children cough, my heart sinks," said Mrs Kalra.
Lung cancer isn't the only threat. According to Dr Siddharth Sahni, a senior oncologist at Apollo Indraprastha, breast cancer has gone from being the 246th cause of death amongst Indian women to one of the top three causes of death.
"The incidence of breast cancer in India was 1 in 200 in 2002. It jumped along with pollution levels to 1 in 28 women getting breast cancer in this country living in metros in 2008," said Dr Sahni. "The ICMR in 2016 now predicts one in 11 women staying in metros will get breast cancer."