Credit: David Paul Morris/Bloomberg via Getty
Across China, a marked rise in people driving electric vehicles has led to a drop in air pollution in many cities. As a result, fewer people are dying from pollution-related diseases.
Outdoor air pollution causes more than four million premature deaths annually, and about one-quarter of them occur in China. Vehicles powered by fossil fuels are a main contributor to that pollution, releasing carbon monoxide, particulate matter, nitrogen oxides and other compounds that are dangerous to humans when inhaled.
EVs started growing in popularity about a decade ago. Around this time, researchers began studying the connection between vehicle electrification and air quality. Although modelling studies projected that EVs would lead to drastic reductions in pollutants from fossil-fuelled cars, they lacked empirical evidence to prove it. Now, large studies in countries including China, and residential areas across the state of California, have measured lower levels of pollutants in the air as more EVs are added to the roads.
China is the world leader in the manufacture and sale of EVs. In the past two decades, it is estimated that the Chinese government has invested hundreds of billions of US dollars into subsidies, tax incentives and other programmes to boost the production and sale of EVs. More than half of all cars sold in China in 2025 were electric.
This has led to a large drop in certain pollutants, according to a study published last month that used satellite data to measure air quality1. Across 150 cities, with an uptake of ‘new energy vehicles’ — which include battery-electric, hybrid and hydrogen-powered cars — carbon monoxide levels are down by more than 30% than an alternate, hypothetical scenario in which all vehicles on the roads of these cities used traditional internal combustion engines. And the amount of particulate matter with a diameter of less than 2.5 micrometres has decreased by more than 23%.
The authors estimate that improved outdoor air quality in these cities prevented 262,000 premature deaths. Long-term exposure to pollutant can cause strokes, heart disease, lung cancer, respiratory diseases and infections.
“The results are both encouraging and sobering,” says Qiangqiang Yuan, a remote-sensing researcher at Wuhan University in China and co-author of the study.
Cleaner California
The public health benefits of fewer gas guzzlers and more fully or partially electric cars on the roads extend beyond China. Throughout California, the rapid adoption of ‘zero-emissions vehicles’ led to improved air quality through reduced nitrogen dioxide concentrations, according to a 2026 study2. The authors analysed daily measurements of nitrogen dioxide in each of roughly 1,700 residential areas from 2019 to 2023. They compared the trends in pollution levels with the number of of EV registrations, finding that for every 200 new zero-emission-vehicle registrations in an area, nitrogen dioxide levels fell by 1.1%. Some places reduced nitrogen dioxide pollution by around 4%.
The China study found that nitrogen oxide concentrations decreased modestly, by 7.92% compared with the non-EV scenario. Enrico Ferrero, an atmospheric physicist at the University of Eastern Piedmont in Vercelli, Italy, thinks this is because nitrogen oxides are uniquely complex chemical products. Unlike carbon monoxide and particulate matter, nitrogen dioxide forms after one of its components, nitric oxide, is emitted from a car’s exhaust and mixes with ozone, a harmful compound already in the atmosphere. Reducing fuel-powered road vehicles, then, is only one piece of the nitrogen oxide emissions puzzle.
