DURHAM, N. C. — If you thought being stuck in gridlock was bad for your mental health, turns out you’ve got more to worry about than just your sanity. A new study finds that air pollution motorists are exposed to during rush-hour traffic might be twice as bad as previously believed.
Researchers at Duke, Emory University, and the Georgia Institute of Technology outfitted customized air sampling devices in the cars of 30 commuters in Atlanta, hoping to measure the actual amount of particulate matter in vehicle air cabins.
Georgia’s capital does happen to use traffic pollution sensors, but exhaust composition is known to change quickly, and sensors often do not account for variables such as road congestion and environmental conditions.
Comparing the car-placed sensors to those alongside the road and monitoring levels of pollution during morning rush hour stretches, the researchers found the in-car sensors indicated up to twice the amount of chemicals that cause oxidative stress.
High levels of oxidative stress are linked to the development of chronic conditions, including cancer, respiratory and heart disease, and sickle cell disease, along with neurodegenerative diseases.
“We found that people are likely getting a double whammy of exposure in terms of health during rush-hour commutes,” explains researcher Michael Bergin, a professor of civil and environmental engineering at Duke, in a news release. “If these chemicals are as bad for people as many researchers believe, then commuters should seriously be rethinking their driving habits.”
The retrofitted sensors were placed in the passenger seats of participants’ vehicles. Each vehicle examined went through 60 commutes.
Higher-than-expected particulate matter levels were observed in pretty much all contexts, whether one drove on the highway or had their windows down.
Different speeds between drivers also had no effect on particulate matter levels.
“There are a lot of reasons an in-car air sample would find higher levels of certain kinds of air pollution,” explains co-author Heidi Vreeland, a doctoral student in Bergin’s lab. “The chemical composition of exhaust changes very quickly, even in the space of just a few feet. And morning sun heats the roadways, which causes an updraft that brings more pollution higher into the air.”
The researchers point the finger at poor urban planning, arguing that cities like Atlanta have too many people, most of whom are forced to go in the same direction at the same time.
Adds Bergin: “There’s still a lot of debate about what types of pollution are cause for the biggest concern and what makes them so dangerous. But the bottom line is that driving during rush hour is even worse than we thought.”
The study’s findings were published last month in the journal Atmospheric Environment.