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Air pollution in major cities worldwide has fallen by up to 60%

Source: IQAir

The lockdowns restricting travel and industry imposed to halt the spread of coronavirus have resulted in unprecedented reductions in deadly air pollution around the world, new analysis shows.

Lockdowns cause air pollution in major world cities to drop by as much as 60%

Last week, IQAir, a global leader in air quality data and solutions, published a COVID-19 Air Quality Report that shows that air pollution levels in 10 major global cities have dropped by as much as 60% during government-mandated lockdowns due to the global COVID-19 pandemic.

Both New Delhi and the country's commercial center Mumbai experienced their best March air quality on record in 2020.
New Delhi: Both New Delhi and the country’s commercial center Mumbai experienced their best March air quality on record in 2020. Source: Reuters/CNN

Knock-on effect of lockdowns sees air pollution drop in major cities

Major cities that suffer from the world’s worst air pollution have seen reductions of deadly particulate matter by up to 60% from the previous year, during a three-week lockdown period, reported CNN last week.

Researchers from IQAir — a global air quality information and tech company — studied 10 major cities around the world which have relatively high numbers of coronavirus cases and Covid-19 lockdown measures.

The study compared levels of harmful microscopic particulate matter known as PM 2.5. The pollutant, which is smaller than 2.5 micrometers in diameter, is considered particularly dangerous as it can lodge deep into the lungs and pass into other organs and the bloodstream, causing serious health risks.

Seven out of the 10 cities studied, including New Delhi, Seoul, Wuhan and Mumbai, saw significant improvements in air quality. 

Those with historically higher levels of PM2.5 pollution witnessed the most substantial drops in pollution.

Analysts chose the three-week timeframe to reflect either the period with the strictest lockdowns, or — during longer lockdown periods such as in Wuhan — to coincide with the peak number of daily reported coronavirus cases.

The report was released to coincide with the 50th anniversary of Earth Day, which this year is focused on climate action.

Air pollution is already a global public health crisis, as it kills seven million people each year, according to the World Health Organization. Reducing global heat-trapping emissions is the best way to clean up our skies and prevent avoidable pollution-related deaths, scientists say.

The report’s authors say that while they do expect air pollution to rise again when economies restart after coronavirus, "out of these extraordinary circumstances, we can see how changes in our society’s activities can have a momentous impact on our environment and the air we breathe," said IQAir’s marketing specialist Kelsey Duska.

Source: CNN

Wuhan: Source: None

Cleaner air recorded around the world

The Indian capital New Delhi — which frequently tops the world’s most polluted city lists — saw a 60% reduction in PM2.5 levels from March 23 to April 13 from the same period in 2019. Both New Delhi and the country’s commercial center Mumbai experienced their best March air quality on record in 2020.

During the initial three-week lockdown period, the number of hours rated as "unhealthy" in New Delhi dropped from 68% in 2019 to 17% in 2020.

On March 25, India placed its entire 1.3 billion population into lockdown, closing factories, markets, shops, places of worship and suspending most public transport services. The world’s largest lockdown was then extended to 3 May.

India is one of the world’s most-polluted countries and an average resident is exposed to air pollution that exceeds the World Health Organization’s target for annual PM2.5 exposure by more than 500%.

Meanwhile, the South Korean capital Seoul saw a 54% drop in PM2.5 levels from February 26 to March 18 from the previous year.

South Korea’s air quality ranks among the worst of Organization for Economic Cooperation and Development (OECD) countries, with some of the highest levels of particulate matter pollution. Last year in March, the government declared air pollution a "social disaster."

In February, South Korea had one of the largest coronavirus outbreaks outside mainland China but aggressive testing and contact tracing methods have brought cases there under control.

And the Chinese city of Wuhan, where the deadly virus was first identified, saw a 44% reduction in air pollution levels from February 26 to March 18 from the same period last year.

The city of 11 million people in central China’s Hubei province was the first city to impose a complete shutdown after Chinese authorities struggled to contain the spread of the coronavirus —  an unprecedented move at the time at the time.

After 75 days those restrictions began to be lifted on April 8 — a milestone in China’s fight against Covid-19 as the country reported nearly zero new local infections.

Over the course of Wuhan’s 10-week lockdown, the city experienced its cleanest air quality on record for the months of February and March. The average concentration of PM2.5 plunged from 63.2 and 43.9 micrograms per cubic meter in February and March 2019 respectively, to 36.8 and 32.9 in the same months this year. The World Health Organization considers anything above 25 to be unsafe.

Source: CNN

Los Angeles saw its longest stretch of clean air on record, over 18 days from March 7 to 28. PM2.5 concentration levels were down by 31% from the same time last year, and down 51% from the average of the previous four years. And in Europe, London and Madrid both experienced reductions in their PM2.5 compared to 2019 during their lockdown periods.
London: Elsewhere, other major cities experienced cleaner air. Los Angeles saw its longest stretch of clean air on record, over 18 days from March 7 to 28. PM2.5 concentration levels were down by 31% from the same time last year, and down 51% from the average of the previous four years. And in Europe, London and Madrid both experienced reductions in their PM2.5 compared to 2019 during their lockdown periods. Source: Reuters/CNN

Reduction in air pollution during lockdowns shows how our habits impact the air we breathe

“While the new coronavirus is dominating international headlines, a silent killer is contributing to nearly 7 million more deaths a year: air pollution," IQAir CEO Frank Hammes said. "Through compiling and visualising data from thousands of air quality monitoring stations, the 2019 World Air Quality Report gives new context to the world’s leading environmental health threat."

“Across the globe, the coronavirus pandemic has had a monumental impact on the way we live,” Mr. Hammes added. “While the human and economic costs are devastating, we are also witnessing how much of air pollution comes from human activity. 

The drastic reduction in air pollution during COVID-19 lockdowns shows how our habits and behaviors directly impact the air we breathe. 

That’s an important insight [after] this unique Earth Day.”

All locations and their data sources are visible on the IQAir AirVisual app and website.

Cleaner air around the world: Lockdowns lead to air pollution drops in major cities Researchers from IQAir — a global air quality information and tech company — studied 10 major cities around the world which have relatively high numbers of coronavirus cases and Covid-19 lockdown measures. The report was released to coincide with the 50th anniversary of Earth Day, which this year is focused on climate action. Source: YouTube/CNN

Air pollution may be damaging ‘every organ in the body’

Air pollution may be damaging every organ and virtually every cell in the human body, according to a comprehensive global review excellently reported by The Guardian last May.

The research shows head-to-toe harm, from heart and lung disease to diabetes and dementia, and from liver problems and bladder cancer to brittle bones and damaged skin. Fertility, foetuses and children are also affected by toxic air, the review found. 

Air pollution is a “public health emergency”, according to the World Health Organization, with more than 90% of the global population enduring toxic outdoor air. New analysis indicates 8.8m early deaths each year – double earlier estimates – making air pollution a bigger killer than tobacco smoking.

Check out the full article and interactive infographic here.

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