A new study confirms that the electrification of vehicles significantly reduces air pollution. Researchers from the USC Keck School of Medicine found that for every 200 zero-emission vehicles (ZEVs) added, nitrogen dioxide levels decreased by 1.1% in the California neighborhood.
The research, published in the journal The Lancet Planetary Health, used high-resolution satellite technology to measure air pollution from 2019 to 2023. The research team summarized their findings in a press release and announced the significant public health ramifications.
“This immediate impact on air pollution is really important because it also has an immediate impact on health,” said senior author Erika Garcia. “We know that traffic-related air pollution can harm respiratory and cardiovascular health in both the short and long term.”
For that purpose, exposure to nitrogen dioxide (NO2) is linked to both cardiovascular risks, such as heart disease, and respiratory diseases, such as bronchitis and asthma attacks. While the same research team made suggestive links between ZEV adoption and reduced NO2 in a previous study using ground-level monitors, this study went a step further with more definitive data sources.
This study divided California into 1,692 districts using DMV ZEV registration data and the Tropospheric Monitoring Instrument (TROPOMI) for daily NO2 measurements. A typical neighborhood gained 272 ZEVs during the study.
To ensure the reliability of the results, the study included several additional analyses. The research confirmed that the decrease in NO2 was not only due to changes related to the pandemic. On the other hand, they also found that neighborhoods that added gas-powered vehicles saw an increase in NO2 pollution.
The study also suggests greater potential to further clean the air. ZEV registrations increased from 2% to 5% of light vehicles in California during the study period, indicating that there is much room for improvement.
Next, the study authors will examine whether more ZEVs are associated with fewer asthma-related hospitalizations and emergency room visits.
Their work adds to extensive research into whether EVs are better for the planet in the long run than their gas-powered counterparts. Despite imperfections like the mines, the findings are clear on that front. The USC team is showing that when it comes to the air we breathe and public health, the benefits of EVs are undeniable.
“These findings show that cleaner air isn’t just a theory—it’s already happening in communities across California,” said Sandrah Eckel, lead author of the study.
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