Fine particle pollution declined rapidly following the implementation of new rules on industrial emissions and the promotion of clean fuels, according to the study, published Monday in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).
The study, which focused on the period from 2013-2017, was conducted by a group of Chinese researchers and scientists.
PM2.5 particulate matter, as this kind of pollution is known, is so small that it can enter the bloodstream, potentially leading to cancer, stroke and heart attack in the long term.
After rapid industrialization and weak regulations left the country with a reputation for smog and bad air quality, Chinese authorities started to take air pollution seriously in 2008.
In 2013, Beijing had PM2.5 concentrations 40 times higher than levels recommended by the World Health Organization (WHO), and the government introduced its toughest-ever clean air policies that year.
The study found "significant declines" in PM2.5 levels across China from 2013-2017, coinciding with new standards for thermal power plants and industrial boilers, the replacement of old factories, and new emissions rules for vehicles.
While the weather can also influence PM2.5 concentrations, the study found it had relatively little impact for the period of the study.
The authors say this "confirms the effectiveness of China's recent clean air actions."
These recent actions have seen Beijing fall out of the top 100 most-polluted cities in Asia in recent years, with overall pollution levels 10% lower across Chinese cities between 2017 and 2018, according to a report by Greenpeace and AirVisual.
Shanghai, the country's largest city and financial capital, has also made environmental advances, such as adopting stringent recycling regulations.
Despite some advances, China still has a huge problem to deal with, and citizens are taking action.
Public pressure has been the driving force of pollution policy in China, and a spate of protests around the issue have occurred in recent years.
However, the government is facing an uneasy balancing act: it must handle the public's environmental concerns but avoid taking action that would slow growth, all while dealing with an economy that has already expanded rapidly -- often without the safety and emissions standards people are now demanding.
Air pollution is a global issue, and India is now home to 22 of the 30 most polluted world cities, according to the Greenpeace/AirVisual report.
In the US, a recent study said air pollution was linked to more than 107,000 premature deaths in 2011 and cost the country $866 billion.