Car rates

Lower car emissions saved US $ 270 billion in one year, researchers say

Top line

Lower vehicle emissions saved an estimated $ 270 billion and nearly 20,000 lives in the United States in 2017, Harvard University study found, as tighter regulations reduced the amount of soot spat out by cars.


The study, published last week by the Proceedings of the National Academy of Sciences, tracked annual costs related to vehicle greenhouse gas emissions and particulate matter such as soot in car exhaust.

Researchers said around 19,800 people died from traffic-related particles in 2017, but the death toll would have been 2.4 times higher – reaching as high as 48,200 – if emissions per kilometer driven remained at 2008 levels.

This drop in deaths accounts for the bulk of the $ 270 billion saved in 2017, with climate change benefits only accounting for 3-19% of the total.

Researchers attributed this drop in particulate matter and greenhouse gas pollution in large part to the use of light vehicles and the strict regulation of fossil fuel companies and automakers.

Key context

Thanks in part to laws such as the Clean Air Act and increasingly stringent Environmental Protection Agency emissions standards, carbon dioxide emissions have reached an all-time high for new cars in 2020. However, transport still accounts for around 29% of the total causes of climate change. greenhouse gas emissions, and five manufacturers, including Volkswagen and Mazda, increased carbon dioxide emission rates from new vehicles between the 2015 and 2020 model years, the EPA reported.


Progress in reducing emissions is being thwarted by purchasing larger vehicles, Harvard researcher and lead author Ernani Choma told The Associated Press. Choma said that “it will be difficult to make substantial progress if we do not adopt more stringent policies”.

Surprising fact

Episodes of severe pollution, such as the heavy mists found in Chinese cities, can be less fatal than chronic exposure to lower pollution levels. Researchers found that acute exposure to particulate matter resulted in significantly lower mortality than chronic exposure to particulate matter, which accounts for the vast majority of traffic-related pollution deaths.

Further reading

“Lower vehicle emissions have lowered fatalities, study finds” (Associated Press)