Researchers from the University of Tennessee have discovered that electric cars in China have an overall impact on pollution that could be more harmful to health than gasoline vehicles.

Researchers have discovered that electric cars cause more air pollution than gasoline cars because the electricity generated to charge electric cars is produced from fossil fuels like coal. They found that the e-cars emit tiny particles like acids, organic chemicals, metals, and soil or dust particles that are harmful to health.

Researchers assessed the health impact on China using overall emission data and emission rates from literature for five types of vehicles - gasoline , diesel cars, diesel buses, e-bikes and e-cars. They then calculated the proportion of emissions inhaled by the population and discovered that e-cars have a lower impact than diesel cars but it is equal to diesel buses while e-bikes yielded the lowest environmental health impact.

"An implicit assumption has been that air quality and health impact are lower for electric vehicles than for conventional vehicles," said Chris Cherry, assistant professor in civil and environmental engineering from the University of Tennessee. "Our findings challenge that by comparing what is emitted by vehicle use to what people are actually exposed to. Prior studies have only examined environmental impact by comparing emission factors or greenhouse gas emissions."

"The study emphasises that electric vehicles are attractive if they are powered by a clean energy source," he said. "In China and elsewhere, it is important to focus on deploying electric vehicles in cities with cleaner electricity generation and focusing on improving emission controls in higher polluting power sectors," he added.