Lia C. Chasar L. Rod DeWeese Mark E. Brigham Dennis A. Wentz William G. Brumbaugh Barbara C. Scudder 2008 Mercury studies conducted as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program have included nationwide reconnaissance samplings of hundreds of stream sites, as well as detailed, process-oriented research at selected sites. These reconnaissance and detailed studies are intended to provide a better understanding of methylmercury bioaccumulation in stream ecosystems over a range of environmental settings. This publication describes trace-element-clean techniques used for collection and processing of aquatic invertebrates and fish to be analyzed for total mercury, methylmercury, and stable isotopes as part of NAWQA studies. application/pdf 10.3133/ofr20081208 en Geological Survey (U.S.) Procedures for Collecting and Processing Aquatic Invertebrates and Fish for Analysis of Mercury as Part of the National Water-Quality Assessment Program reports