The Air That Kills in India

Agence France-Presse â€" Getty Images Commuters awaiting a bus in New Delhi during the morning rush hour last month.

The thick haze of outdoor air pollution common in India today is the nation’s fifth-largest killer, after high blood pressure, indoor air pollution (mainly from cooking fires), smoking and poor nutrition, according to a new analysis presented in New Delhi by the Boston-based Health Effects Institute. In 2010 outdoor air pollution contributed to over 620,000 premature deaths in India, up from 100,000 in 2000.

‘’It’s not just breathing bad air,’’ said Aaron Cohen, the principal epidemiologist at the institute. A host of diseases is related to air pollution, like cardiovascular diseases that lead to heart attacks and strokes, respiratory infections and lung cancer.

The new analysis was drawn from “The Global Burden of Diseases, Injuries, and Risk Factors Study” for 2010, a sweeping worldwide study published in December involving 450 experts. The report found that outdoor air pollution in the form of fine particles contributed to 3.2 million deaths globally in 2010, up from 800,000 just 10 years earlier.

Scientists and health researchers have come to understand that fine particulates are a far more signif! icant public health threat than had previously been known.

In Asia, exhaust from vehicles accounted for 20 to 35 percent of air pollution, said Dan Greenbaum, president of the Health Effects Institute. Emissions from factories and power plants, the burning of biomass like wood and plant matter, and dust are also big factors. Pollution worsens in the winter when people burn wood, coal and other fuels for heating.

Given the weight of the evidence, the question now is how to inform national policy, said Kalpana Balakrishnan, director of the Indian Council for Medical Research’s Center for Advanced Research on Environmental Health, in Chennai in southern India.

The Center for Science and Environment, a Delhi-based nongovernmental organization that helped organize Wednesday’s workshop on the report, suggests making strict air quality standards in Indian cities legally binding. It advocates etting an early timeline for the nationwide introduction of more stringent vehicle emissions rules â€" namely, Euro V and Euro VI, standards introduced in the European Union.

India’s ministry of environment and forests has recommended upgrading vehicle fuel to low-sulfur diesel, retrofitting old vehicles, drafting guidelines on cleaner construction methods and other measures.

Sunita Narain, director general of the Center for Science and Environment, said the group was pushing for better public transportation in New Delhi, including more buses, a tax on diesel-powered cars and higher parking fees to rein in car use.

Trucks are barred from driving in the capital during working hours, but bypasses should be built to the east and west of the city so that they don’t have to enter at all, Ms. Narain said.

Enforcement is notoriously weak in India. But New Delhi defied all expectations! when its! buses and taxis and more than 50,000 autorickshaws began converting to cleaner-burning compressed natural gas in 2001 as a result of a Supreme Court mandate for commercial vehicles.

But the substantial reduction in air pollution after the switch to C.N.G. has since been canceled out by the sheer number of vehicles added to the city’s roads, including older, highly polluting vehicles like overloaded trucks that spew exhaust.

Environmental and health experts hope the new analysis on air pollution and health will lead to redoubled policy efforts in India. ‘’This calls for urgent and aggressive action to protect public health,’’ Ms. Narain said.