How bad is Delhi’s air? Like smoking half a pack of cigarettes.
By Pranshu Verma, Supriya Kumar and Kevin Crowe
NEW DELHI — Tens of millions of people in India’s capital city are breathing in polluted air that is equivalent to smoking roughly nine cigarettes a day, or about half of a standard pack, according to a Washington Post analysis of 2½ months of government data.
Every winter, for months at a time, Delhi is blanketed by toxic smog, and this year has been no different. Though people try to limit the time they spend outside, children need to go to school, parents need to go to the office, and most days the roadways are still choked with motorcycles and scooters and rickshaws, navigating through a sepia haze. Delivery drivers, bricklayers and others who spend their days outdoors are especially vulnerable.
To quantify the toxicity of the air and its impact on human health, The Post analyzed 75 days of Indian government pollution data — spanning Oct. 18 to Dec. 31 — from 40 air monitoring stations spread across the capital region. Each station collects hourly data on chemicals in the atmosphere, such as particulate matter 2.5 (PM 2.5) and particulate matter 10 (PM 10), which are known to cause lung and heart issues when inhaled in large amounts.
Reporters calculated the daily average of PM 2.5, the most harmful measure of India’s poisonous air, then converted those figures into daily cigarette intake using a formula developed by scientists at the University of California at Berkeley. The Post verified its calculations with researchers at the University of Chicago and the Center for Research on Energy and Clean Air (CREA), an independent climate think tank that provided the government pollution data.
While the data averaged out to nine cigarettes a day per person across Delhi, some days were much worse — and some neighborhoods were more adversely affected. On Dec. 14, for example, Delhiites inhaled air that was as toxic as smoking almost 18 cigarettes a day. And in Wazirpur, an industrial area in the city’s northwest, residents breathed in a daily average of 12 cigarettes.
Despite numerous government initiatives over the years to purify the winter air in Delhi, it remains as toxic as ever. After analyzing and converting data from roughly the same period a decade ago — covering November 2015 to January 2016 — reporters arrived at the same figure: nine cigarettes a day, on average.
Tanushree Ganguly, director of the Air Quality Life Index at the University of Chicago’s Energy Policy Institute in New Delhi, said India’s sustained pollution crisis is due in large part to the government’s “reactive” approach — favoring temporary emergency measures, like the use of water sprinklers to reduce dust, instead of proactive efforts, such as limiting vehicular and industrial emissions.
“We are not going to see any significant decline in pollution levels going forward,” Ganguly said. “People are losing years from their life.”
India’s Ministry of Environment, Delhi’s Office of the Chief Minister and Delhi’s Department of Environment did not respond to requests for comment.
No solutions in sight
Air pollution in Delhi intensified in the mid-1990s as the Indian economy opened up and the nation’s capital underwent rapid industrialization and urban growth. More vehicles clogged the roads , and more factories spewed out chemical clouds. Cities struggled with sanitation and waste management issues.
Alarmed in part by rising air contamination, India’s Supreme Court in 1996 ordered the highest-emitting factories in Delhi to relocate or shut down. But the crisis far outpaced efforts to track it: An automated air-quality monitoring network wasn’t set up until 2015. By then, pollution levels were already extreme. Data from the World Health Organization (WHO) showed that in 2010, the city’s annual average concentration of PM 2.5 stood at 153 micrograms per cubic meter, more than 30 times the WHO’s recommended limit.
Not much has changed in the years since. During the 2015 pollution season, Delhi’s average PM 2.5 level stood at 207, roughly equal to nine cigarettes per day. The only noticeable dip occurred in 2020, which scientists largely attributed to India’s pandemic lockdown measures.
On average, Delhi residents are losing eight years of their lives, according to the University of Chicago’s Air Quality Life Index , which calculates the effect of exposure to PM 2.5 on life expectancy.