A recent study conducted by the Georgia State University School of Public Health highlights the beneficial impact of planting trees and bushes near highways in mitigating air pollution resulting from motor vehicle emissions, known to contribute to various health issues.

During two separate three-month periods, researchers monitored air quality at five locations along interstates and highways in metro Atlanta. A comparison between sites with and without vegetation revealed notable reductions in air pollutants. Specifically, areas with natural or ornamental vegetation exhibited a 37% decrease in soot and a 7% decrease in ultrafine particles compared to similar sites lacking greenery.

“Trees and bushes near roadways don’t solve the problem of air pollution caused by motor vehicles, but they can help reduce the severity of the problem,” the researchers explain.

Clear link

A mounting body of research has established a clear link between motor vehicle emissions and various health issues, including asthma, chronic bronchitis, lung cancer, and heart attacks.

Addressing the elevated levels of pollution near roadways is imperative, the authors emphasize, particularly given that 45 million individuals in the United States reside, work, or attend school within 300 feet of a major highway.

Roadside vegetation serves as a vital tool in combating air pollution by offering multiple mechanisms to mitigate its effects, such as providing a large surface area for small particles to adhere to.

The latest study expands upon prior research on the role of vegetation in reducing air pollution by conducting extensive sampling across multiple sites over an extended period. Additionally, researchers integrated a model to factor in variables like wind direction, traffic volume, and distance from the highway.

However, it’s essential to note that while roadside vegetation can effectively reduce particulate air pollution, it does not address carbon dioxide emissions or ozone pollution. To comprehensively tackle the health hazards associated with highways, municipalities must explore broader strategies. These may include enhancing public transportation, as well as developing and enhancing infrastructure for bicycles and pedestrians to create safe, pleasant, and convenient alternatives to motor vehicle use.

“We should plant more trees along roadways because they provide benefits that go beyond aesthetics,” the authors conclude. “But I don’t want to give anyone the impression that we can solve all of the problems associated with motor vehicle emissions simply by planting trees.”