India’s capital may have the worst air quality in the world on some days, but a new report shows that nationally, the air in the world’s second-most-populous country is far less polluted than in China.
In fact, China’s air is more than twice as dirty as India’s, according to recently released estimates by the World Bank.
The bank’s “Little Green Data Book” of environmental indicators, unveiled last week, included a new gauge of air pollution. To the standard measures of environmental health–including forest cover and carbon emissions–it added PM 2.5 levels, which measure airborne particles smaller than 2.5 microns.
These tiny pollutants are microscopic and can enter the lungs and even pollute a person’s blood stream. They are linked to severe health problems including lung cancer.
“These data show that in many parts of the world exposure to air pollution is increasing at an alarming rate and has become the main environmental threat to health,” the forward of the World Bank book said. “Exposure to ambient PM 2.5 pollution in 2010 resulted in more than 3.2 million premature deaths globally.”
Using this measure, India’s air is far from clean. The World Bank data put the South Asian nation’s annual mean PM 2.5 at 32 micrograms per cubic meter. That’s three times the bank’s recommended level of 10 or less, but in line with the global average. It is also well below China’s mean annual exposure of 73 micrograms per cubic meter. .
Of the 200 countries in the book, only the United Arab Emirates did worse than China.
India’s environmental rankings fared better than China’s in other categories as well. India’s energy use and carbon emissions per capita were less than one third of those in China.
India’s PM 2.5 air pollution average is on par with other fast-growing Asian countries, but will likely rise as its economy expands.
The World Bank data showed that air quality deteriorates as countries evolve from lower income levels and become more affluent. Air only starts to improve once countries attain high-income status, which the World Bank defines as having gross national income per capita of $12,746 or more.