A new study has found China prevented around 10,000 air pollution-related deaths after closing down industrial activity and travel during coronavirus lockdown.
The results of the report from the University of Birmingham, published in The Conversation, revealed a 63% reduction in “nitrogen dioxide concentrations” in Wuhan, the country’s epicentre of COVID-19, while residents were ordered to stay at home between 23 January and 8 April.
Research conducted by professors Matt Cole, Bowen Liu and Robert Elliot said the lockdown “may have prevented 496 deaths in Wuhan” and “10,822 in China as a whole”.
It even claimed the total number of saved lives “may even outweigh the official Chinese death toll from COVID-19 itself”, which currently stands at 4,933.
The Chinese government closed down much of its industrial activity and restricted air and car travel to limit the spread of the killer virus.
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As such, levels of concentrated pollutants such as nitrogen dioxide (NO2) that are usually influenced by weather conditions such as “wind speed, wind direction and temperature” that significantly “affect local pollution concentrations” were down.
Researchers used machine-learning techniques to strip out the effects of weather on pollution levels – or “weather normalised” levels – to show the levels of uninfluenced raw pollution levels in Wuhan.
It said that Wuhan was locked down ahead of 29 other cities in China, with results showing the city “experienced a significant reduction in concentrations of NO₂ and particulate matter (PM10) – sometimes known as floating dust – as a result of the lockdown.”
NO2 levels experienced in Wuhan during the two weeks before other cities went into lockdown fell by 63% while floating dust concentrations sharply fell by 35%.
However, not all aspects of air quality improved, with the research showing that “significant reductions in concentrations of sulphur dioxide (SO₂) or carbon monoxide (CO) were found”.
The report also went on to say that it was not only China that had experienced “significant” drops in pollution levels “as a result of COVID-19 lockdowns”.
It highlighted that in the UK, concentrations of NO2 “reguarly exceed WHO guidelines” - although it pointed out it was “less frequently and by a smaller magnitude” than levels recorded in China.
A study in late March, conducted by scientists from the University of York, analysed data from the London Air Quality Network and UK Automatic Urban and Rural Network.
It showed pollutants had fallen to levels lower than the average of the past five years.
Monitoring of European cities, many of which are in lockdown over the pandemic, by the European Environment Agency also reveals large decreases in air pollution, particularly NO2.
The reduction in nitrogen dioxide in UK and European cities is likely to be caused by lower levels of traffic, as well as decreased industrial and fuel burning activity, experts said.
Britain's roads saw an increase in traffic this week, as amended coronavirus lockdown rules meant some workers could return to their jobs.
Commuters took to roads and public transport networks after Boris Johnson advised those who need to return to working away from home to do so, in a public address on Sunday night.
Congestion on major roads such as the M25 was reported for the first time since the UK entered lockdown on 23 March.