The unexpected side effect of coronavirus ravages on the globe is an immediate improvement of the environment.
Air pollution with the toxic gaseous nitrogen dioxide over Hubei Province and Northern Italy has been measurably reduced after the shutdown of community life has minimized road traffic and factory production.
Now, American researcher Marshall Burke of Stanford University has calculated that the reduced environmental pollution may already have saved thousands of lives.
Burke's calculations are based on observations from sensors in Chengdu, Shanghai, Guangzhou and Beijing that measured the level of particles less than 2.5 micrometers / 0.0025 millimeters - called PM2.5 articles.
Several studies have found a close relationship between PM2.5 particle exposure and premature death due to cardiovascular disease.
Because PM2.5 particles are so small and light, they hang longer in the air, where an inhalation can pull the potentially toxic particles far down into the branches of the lungs.
During the Chinese quarantine in January and February, the number of PM2.5 particles decreased by 15-17 micrograms per cubic meter compared to previous years. This represents a decrease of 10-30 percent compared to the same period in previous years. However, to adjust for uncertainties, Marshall Burke set the decline to 10 micrograms / m3, so his estimates are conservative.
A previous study has estimated how a fall in air pollution affects mortality rates for different age groups, and using those numbers, Burke found the theoretical, potential decrease in particle pollution deaths.
The calculations show that the reduction of pollution in the months of January and February may have saved the lives of 4,000 Chinese children under five and 73,000 Chinese over 70.
There are 24 times as many people who have died from coronavirus in China in total.
Although the calculations do not take into account a number of factors, such as how air pollution is in the homes of citizens and the importance of quarantine on other facets of society, air pollution is undoubtedly a major, invisible killer worldwide.
In 2019, the European Environment Agency estimated that PM2.5 particles led to the early death of 412,000 Europeans.
This post was published on April 1, 2020 4:23 am