Increase in Use of Synthetic Chemicals (IMAGE) Duke University Caption Three graphs show the rates of increase in the use of synthetic chemicals in recent decades relative to other agents of global change such as nitrogen fertilizer and CO2. The middle graph (red) shows increases in chemical diversity in the US and globally; the right graph (green) shows global trade values as a proxy for the mass of chemicals. Credit Emily Bernhardt, Duke University 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.