Minnesota Lake Sediment (image) University of Minnesota Caption Civil engineering professor William Arnold, University of Minnesota, and his research team determined that triclosan and associated derivatives and dioxins are found in increasing amounts in Minnesota freshwater lakes. Part of the research included gathering sediment cores about one meter long (pictured here) from eight Minnesota lakes. Credit William Arnold / University of Minnesota Usage Restrictions With proper credit. 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.