AUSTIN (KXAN) — In groundbreaking research, scientists are directly linking the adoption of electric vehicles (EVs) to decreases in respiratory-related emergency room visits.

Though presumed health benefits of zero-emissions vehicles when compared to traditional internal combustion engines are nothing new, a team of researchers from the University of Southern California Keck School of Medicine is now showing the link with real-world data.

Researchers analyzed total electric vehicle registration, air quality data, and asthma-related emergency room visits across California between 2013 and 2019. The authors used data from before the year 2020 to avoid COVID-related influences on air quality, even though electric vehicle adoption was lower at that time.

“There’s evidence that zip codes that had greater increases in the number of EVs had greater declines in asthma-related emergency department visits,” Dr. Sandy Eckel, author of the study, said.

More specifically, the study found that for every additional 20 electric vehicles per 1,000 people, there was a 3.2% drop in the rate of asthma-related emergency visits and a small, suggestive improvement in air quality levels.

Why pollution from gas-powered vehicles is unhealthy

“Internal combustion vehicles produce a variety of air pollutants, including nitrogen dioxide,” Dr. Eckel said. “When inhaled, air pollutants like nitrogen dioxide have a variety of health impacts. The respiratory system is the most sensitive and impacted first.”

Dr. Eckel says that people with asthma are at increased risk of respiratory problems when air pollution levels are worse, potentially leading to emergency room visits.

Study notes slower EV growth in lower socioeconomic areas

“The transition to EVs is really an opportunity to address environmental justice issues,” Dr. Eckel said. “[Underserved communities] are often overburdened by environmental exposures like air pollution, and air pollution-related diseases like asthma.”

Dr. Eckel says that policymakers should consider incentives for purchasing used EVs to assist lower-income residents with transitioning away from gas-powered vehicles and installing community charging stations in neighborhoods where residential chargers are cost-prohibitive.