The winner is: China although New Delhi can give Beijing a good run for its money.
The final paragraph is interesting - the Chinese are "adapting" to pollution (and can afford to more easily after years of rapid growth). The story in India is not so encouraging.
We are moving to a world of adaption with prevention being pushed off the climate change negotiation table of doom.
Who Has Dirtier Air: China or India?[Bloomberg Business Week]
"On an average day, the view from the window of a New Delhi apartment is even smoggier than that from the window of a Beijing high-rise, as the New York Times recently reported. (The 7.5 million cars on New Delhi’s roads, up from 800,000 in the early 1970s, certainly hasn’t helped air quality.) But on a country-to-country basis, China still ranks dead last globally in terms of average exposure to PM 2.5—fine particulate air pollution that poses a severe threat to human health—according to data compiled for the 2014 Environmental Performance Index by scientists at Yale and Columbia universities.Bad air in China reaches far beyond Beijing, which has received the greatest international media attention for its gray skies—partly because it is home to the highest concentration of foreign journalists in China. A quick perusal of newspaper headlines within China easily shows how widespread the problem is: In October, severe pollution forced school closures and shut down a major airport in the northern Chinese city of Harbin. A long bout of toxic air in November also forced school closings in Shanghai.
Alas, Chinese cities aren’t Asia’s only smog-shrouded metropolises. As Angel Hsu, lead author of the Environmental Performance Index, points out, “South Asia has the world’s worst air pollution as a region. It’s worth noting that it’s not just China, or India even, that suffers from poor air quality. Bangladesh, Pakistan, and Nepal all suffer from both poor household air quality”—exacerbated by indoor coal-burning stoves—“and outdoor air pollution,” as measured by PM 2.5 levels. When both indoor and outdoor air quality are considered, Bangladesh ranks lowest overall.
The index, which was released at the World Economic Forum in Davos, places Switzerland tops among 178 countries and regions for all environmental indicators—including air quality, water quality, sanitation, forest and fisheries conservation, climate control policies, and other measures. The U.S. ranks 33 overall.
One bright spot is increasing access to potable water worldwide. “The number of people lacking access to clean drinking water has decreased from 1.04 billion in 2000 to 759 million in 2011,” says Hsu. And one global brown spot: the rising number of people breathing unhealthy air—in China, India, and beyond. There are now 1.78 billion people who regularly inhale air with pollution levels 2.5 times greater than what the World Health Organization deems safe—up 606 million from 2000. In China, a rising tide of urban dwellers are wearing air-pollution masks and buying home air-filtration devices; so far India’s urbanites have been slower to adopt such partial protective measures."