Thursday, November 19, 2020

Poor air inflicts billions of premature deaths in Asia

Traffic jam in Beijing: But China has made big strides towards air quality improvement. 

Image: By public domain, via Wikipedia Commons

Air pollution by tiny particles is among the world’s worst health risks. In South Asia, poor air is as bad as it gets.

NEW DELHI, 22 October, 2020 − Poor air costs lives, but finding out just how many of them will come as a shock to many residents of South Asia’s big cities.

In India’s capital, New Delhi, just going outside and breathing the air can shorten your life by more than nine years, according to a new report into the region’s air quality that measures the effects of pollution on life expectancy.

For millions of people across across north-west IndiaPakistan and Bangladesh, it will be bad news − despite the Covid crisis − because of the current surge in air pollution in the region.

But none of the people of four countries, India, Pakistan, Bangladesh and Nepal, will be happy with the prediction that their lives will be shortened unless their governments take air pollution seriously.

New Delhi is the worst single example in the four, but few of their citizens − a quarter of the world’s population − will escape.

Bangladesh worst hit

Averaged across the whole population, the people of Bangladesh suffer most from air pollution in any country, with their average life span cut short by 6.2 years.

An air quality index (AQI) provides daily air quality assessments, but not the actual health risk. An air quality life index (AQLI) goes further: it converts particulate air pollution into perhaps the most important air pollution metric that exists: its impact on life expectancy.

The report is the work of the Energy Policy Institute at the University of Chicago (EPIC), which has recently updated its AQLI, based on research by its director Michael Greenstone that quantified the causal relationship between human exposure to air pollution and reduced life expectancy.

While the report makes grim reading for nations south of the Himalayas, it does offer some hope, saying that the people of China can see marked improvements since their government began clamping down on polluting industries in 2013.

The report uses two measures to calculate lower expectations of life expectancy: the more stringent World Heath Organisation guidelines (WHO) and the limits imposed by the governments concerned.

“The threat of coronavirus is grave and deserves every bit of the attention it is receiving [but] embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives”

It says air pollution shortens Indian average life expectancy by 5.2 years, relative to what it would be if the WHO guidelines were met, but by 2.3 years relative to the rate if pollution were reduced to meet the country’s own national standard.

Some areas of India fare much worse than the average, with air pollution shortening lives by 9.4 years in Delhi and 8.6 years in the northern state of Uttar Pradesh, the report’s India fact sheet 2020 says.

Similarly, the Pakistan sheet says the average Pakistani’s life expectancy has been shortened by 2.7 years, while air pollution cuts lives by more than 4 years in the most polluted areas.

Naming Bangladesh as the world’s most polluted country, EPIC’s report says air pollution shortens the average citizen’s life expectancy by 6.2 years, compared to what it would be if the WHO guidelines were met.

Again, some areas suffer far more, with lives cut by about 7 years in the most polluted district. In every one of the country’s 64 districts, particulate pollution levels are at least four times the WHO guidelines.

Possible underestimate

Surprisingly Nepal, which unlike its southern neighbours is not normally associated with air pollution, also had serious problems with its crowded and polluted cities. As a result, life expectancy there is cut by 4.7 years across the whole population.

“Though the threat of coronavirus is grave and deserves every bit of the attention it is receiving − perhaps more in some places − embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives,” says Professor Greenstone.

The science of air pollution, and the impact of poor air on the human body, is evolving rapidly, and some Asian scientists have expressed reservations about the accuracy of some of the calculations. However, none of them disputes the fact that millions are dying early because of the pollution.

The report concentrates on the effect of the smaller particulates that are known to do the most damage to lungs, and to enter the bloodstream, and it may in fact be underestimating the overall effects of poor air quality. − Climate News Network

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Nivedita Khandekar is an independent journalist based in New Delhi, covering development and the environment: nivedita_him@rediffmail.com and on twitter at @nivedita_Him

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