Spreading Fertilizer (IMAGE) Duke University Caption Fertilizer derived from treated human waste is commonly spread throughout the United States by equipment such as this. There are questions, however, about what chemicals used by people in commercial products might make it through the treatment process and potentially accumulate in the environment. Researchers at Duke University have come up with a quick and inexpensive test to pinpoint which chemicals present in such fertilizers warrant further study. Credit Ryan Holzem, graduate student in civil and environmental engineering at 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.