Slider (IMAGE) Moscow Institute of Physics and Technology Caption Russian researchers have shown free radical concentrations in lichens to be directly related to air pollution. By showing that atmospheric air quality determines the concentration of radicals in lichens, we prove that electron paramagnetic resonance spectroscopy can be used for environmental monitoring in cities. Credit MIPT Press Office Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.