Isoprene, a volatile organic compound (VOC), is produced by vegetation and worsens the air quality of many cities and suburbs when it reacts with man-made pollution, such as the nitrogen dioxide (NO2) emitted by cars, to create smog and particulate matter (PM). This phenomenon is most prominent in the Southeast United States with their abundance of forests coupled with many heavily-populated and urban areas.
Isoprene is largely correlated with the two most dangerous air pollutants: ground-level ozone and PM.Ozone near the surface of the earth is known to be toxic to humans. Ozone pollution can lead to shortness of to breath and coughing, among other respiratory health concerns. These particulates are small, yet harmful, and are easily inhaled and can irritate damage the throat and lungs. These particles are suspended in the air for long periods of time, contributing to long-term air pollution in areas. Despite all the benefits we get from greenery in urban spaces (cooler temperatures, less runoff, less erosion), the synergistic interaction between vegetation and human pollutants are deadlier than ever. As trees undergo stress like heat and drought, they are producing an increasing amount of isoprene and other VOCs that are harmful to humans. Ozone and PM also become more damaging as the temperatures increase, so many of these issues are connected with climate change. Research on isoprene is considered new, having started in the last decade, but its threat to public health should be a main concern of authorities.
Research has shown that invasive species of trees produce more BVOCs than native species. Since invasive species can tolerate a larger range of outside stimuli, they will better withstand the environmental changes from climate change when compared to the native species. Harmful air quality can be mitigated with more precise and thought-out planning and analyzing the interactions between human and nature. Certain trees emit less isoprene than others, which is an aspect urban planners can ponder as they include vegetation in cities. By being more conscientious of man-earth relationships, threats to public health can be alleviated starting now and even more so in the future.
