Dr. H. Barry Dellinger, Ph.D., the Patrick F. Taylor Chair of Environmental Chemistry at Louisiana State University in Baton Rouge, says that inhaling such pollutants exposes the average person up to 300 times more free radicals daily than from smoking one cigarette.
The researchers believes that the new findings may help in understanding why non-smokers develop tobacco-related diseases like lung cancer.
"Free radicals from tobacco smoke have long been suspected of having extremely harmful effects on the body," Dellinger said.
"Based on our work, we now know that free radicals similar to those in cigarettes are also found in airborne fine particles and potentially can cause many of the same life-threatening conditions.
"This is a staggering, but not unbelievable result, when one considers all of diseases in the world that cannot currently be attributed to a specific origin," Dellinger added.
Scientists have long known that free radicals exist in the atmosphere. These atoms, molecules, and fragments of molecules are highly reactive and damage cells in the body.
The newly detected molecules, which Dellinger terms persistent free radicals (PFRs), form on airborne nanoparticles and other fine particle residues as gases cool in smokestacks, automotive exhaust pipes and household chimneys.
Once PFRs are inhaled, Dellinger suspects they are absorbed into the lungs and other tissues, where they contribute to DNA and other cellular damage.
"You basically have to be in certain places to inhale transient gas-phase radicals," Dellinger said.
"You'd have to be right next to a road when a car passes, for example. Whereas we found that persistent radicals can last indefinitely on airborne fine particles. So you're never going to get away from them,"ellinger added.
The study was presented at the 236th National Meeting of the American Chemical Society.