Method Detection/Quantitation and Calibration
Over the past few years, the Forum on Environmental Measurements (FEM) at the direction of the Science and Technology Policy Council (STPC) conducted a review of the US Environmental Protection Agency’s (i.e., EPA’s or Agency’s) method detection limits, method quantitation limits, and calibration curves. This brief summary reviews the purpose of this effort, describes the products developed, and summarizes the results.
After the Office of Water (OW) convened a Federal Advisory Committee Act (FACA) Workgroup to discuss method detection and quantitation for the Clean Water Act (CWA), several organizations wrote letters to the Agency thru the FEM to request that a serious look be taken at all the procedures used across the Agency to find a single procedure for use by the entire Agency not just OW. The FEM’s charge was to consider all the existing information (e.g., the FACA report; approaches that exist across all the Agency programs) and make a recommendation for greater consistency across the Agency for method detection and quantitation. At the Environmental Measurement Symposium within the first year of work, the same issue was identified for calibration curves; so, the charge was expanded to also review all information for calibration curves and make a recommendation for greater consistency across the Agency for calibration, as well.
During the process of capturing the current procedures with the use and needs identified for method detection limits, method quantitation limits (3pp, 24KBAbout PDF), and calibration curves (8pp, 115KBAbout PDF) in each of our programs, an Environmental Measurement Glossary (PDF)About PDFwas established to allow communication between programs. This ability to converse about existing processes in EPA regulations made identification of a single procedure not practical. A summary table (7pp, 77KBAbout PDF) was also generated for method detection and quantitation to provide information at a glance about what each program uses. One positive addition was identified for calibration curves from an alternative that was presented to us during consideration of existing practices. The Relative Standard Error calculation has now been published in the Federal Register for consideration by the Office of Water, Office of Science and Technology in addition to the Office of Solid Waste and Emergency Response, Office of Resource Compliance and Recovery.
While the removal of calculations from exiting regulations is not practical, our programs have gained a knowledge and understanding of cross-Agency tools for future use. General information and some detail, however, has been captured for all existing processes and, with the glossary, is a phenomenal resource to allow for proper application of techniques.