Trees Can Produce Smog And Unhealthy Air-Borne Particulate Matter

Posted by Milton Recht:

From "Darn Those Trees, They're Making Smog!" on ScienceBlog:

It has long been known that trees produce and emit isoprene, an abundant molecule in the air known to protect leaves from oxygen damage and temperature fluctuations. However, in 2004, researchers, contrary to popular assumptions, revealed that isoprene was likely involved in the production of particulate matter, tiny particles that can get lodged in lungs, lead to lung cancer and asthma, and damage other tissues, not to mention the environment.

But exactly how was anybody’s guess.

Jason Surratt, assistant professor of environmental sciences and engineering at the Gillings School of Global Public Health, now reveals one mechanism by which isoprene contributes to the production of these tiny, potentially health-damaging particles.

The study found that isoprene, once it is chemically altered via exposure to the sun, reacts with man-made nitrogen oxides to create particulate matter. Nitrogen oxides are pollutants created by cars, trucks, aircrafts, coal plants and other large scale sources.