99% of the world's population is exposed PM 2.5 at unhealthy levels according to Lancet Planetary Health's recently released study. The Washington Post author Kasha Patel highlights:

In 2019, they found 0.001 percent of the global population is exposed to levels of PM 2.5 pollution that the World Health Organization deems safe. The agency has said annual concentrations higher than 5 micrograms per cubic meter are hazardous.

by Andy Fell | Oct 11, 2021 | Environment, Features, The Big Question

A recent study by the University of Leeds and the Southern University of Science and Technology in Shenzhen divulged PM2.5 had only a small reduction across China and it was not lowered at all in Northeast China. The PM2.5 reduction of 11% across China was disappointing in comparison to the reduction 27% of NO2 across China.  

More and more we are seeing results from recent studies showing a correlation between higher COVID-19 death rates and people who live in air pollution riddled areas. Both in Italy and the United States, people that reside in areas with higher concentrations of PM2.5 in the atmosphere are at least 12% more likely to not survive a bout with COVID-19. These findings are consistent with the findings from the 2002-2003 SARS outbreak that claimed 349 lives in China. 

The New York Times writer, Nadja Popovich, reports that after nearly a decade of improving the air quality nationally, the US EPA's data shows that PM 2.5 has increased in the past two years. This 180 turn of progress has been identified as likely primarily coming from increases in driving and the burning of natural gas. However, in the West, wildfires has been a large cause of the increase as well. Researchers suggest that due to a decrease of enforcement of the Clean Air Act, less businesses are concerned with their pollution.