Did China’s Air Get Better in 2018?

New data analysis from Smart Air shows that air quality improved in 14 out China’s 15 largest cities. This data suggests China’s “war on air pollution” seems to be working.


PM2.5 pollution in major Chinese cities


This analysis uses over 21,000 daily average PM2.5 data points from official sensors around the country. 



Famous for its smog, Beijing’s quality improved 14% over 2017. That year was already Beijing’s cleanest on record.


Beijing PM2.5 pollution 2017v2018




Chengdu’s PM2.5 fell 12%, following a 15% decrease the year before.


Chengdu PM2.5 pollution 2017v2018



Xi’an has finally seen some improvement. In 2017, Xi’an’s pollution was up 7%. In 2018, Xi’an saw pollution fall 17%.

Xi'an PM2.5 pollution 2017v2018


Most of Xi’an’s improvement came in January and February. Air quality has been roughly similar to the prior year since then.


Xi'an monthly PM2.5 pollution 2017v2018



The biggest improvement happened in China’s northeast. Harbin saw the largest decrease in PM2.5, down 32%.


Harbin PM2.5 pollution 2017v2018


Harbin’s air quality improvement came mostly in the winter. The northeast may have been slow to receive the benefits from last year’s switch of winter heating from coal to natural gas.


harbin monthly PM2.5 pollution 2017v2018


Last winter, there were reports of natural gas shortages and delays as the sudden switch rolled out, particularly in places farther from Beijing. As these supply difficulties decreased, Harbin’s air has caught up with Beijing.



The improved roll out of natural gas winter heating could also explain Shenyang’s 19% improvement in air quality.


Shenyang PM2.5 pollution 2017v2018



Farther south—outside the range of winter heating—air quality improvement has been smaller. Shanghai air quality also improved in 2018, albeit at a more modest pace of 8%.


Shanghai PM2.5 pollution 2017v2018



Similar to Shanghai, Shenzhen’s air pollution was down 9%.


Shenzhen PM2.5 pollution 2017v2018



Guangzhou’s PM2.5 fell a smaller amount, just 3%.


Guangzhou PM2.5 pollution 2017v2018



Chongqing saw air quality improve 15% over 2017.


Chongqing PM2.5 pollution 2017v2018


Despite Progress, China’s Air is Still Toxic

Despite the improvement, all 15 cities are far above the World Health Organization’s annual limit. Even China’s cleanest major city, Shenzhen, averages over twice the limit. Simply put, anyone living in any of China’s major cities is breathing harmful air on an average day.


PM2.5 pollution in major Chinese cities


This limit matters because studies have shown that PM2.5 raises blood pressure, inflammation, and rates of heart attacks and strokes. This is true even at PM2.5 levels 50% below the lowest average in China.


Residents across China may need to hold their breath before their cities catch up with major cities in the developed world. Compared to cities like Tokyo, New York, and London, China still lags far behind.


major cities average PM2.5

Studies Document Protective Effects of Purifiers, Masks

Despite the harms of PM2.5, studies have found that wearing masks prevents harmful effects on blood pressure and heart rate variability. Similarly, placebo-controlled studies of air purifiers have found that reducing particulate in the home prevents harm to blood pressure, inflammation, and immune response—even among young, healthy twenty-year-olds.


Smart Air is a certified B Corp committed to combating the myths big companies use to artificially inflate the price of clean air. To help people living in polluted cities protect themselves, Smart Air provides empirically backedno-nonsense purifiers and masks, thereby helping to lower the cost of clean air.

Free Guide to Breathing Safe

Want to learn more about breathing clean air? Join thousands more and stay up to date on protecting your health.

Leave a Comment

Smart Air low cost purifiers

Smart Air is a social enterprise and certified B-Corp that offers simple, no-nonsense air purifiers and provides free education to protect people from the harms of air pollution. We are proud to be the only certified B-Corp dedicated to fighting air pollution.

Certified B-Corp air purifier company