USEPA (United States Environmental Protection Agency) Method Study 37, SW-846, Method 3050, Acid Digestion of Sediments, Sludges, and Soils

摘要

An interlaboratory collaborative study was conducted to determine the precision and accuracy of Method 3050 for the analysis of 23 elements in sediments, sludges and soils. It includes instructions for quality control, sample preparation and analysis of samples by AA direct aspiration. The study design was based upon Youden's non-replicate plan for collaborative tests of analytical methods. Initially, 14 solid wastes were collected, dried, homogenized and analyzed for the 23 elements of interest by Inductively-Coupled Plasma. Based upon this data, seven solid wastes were selected that contained the most naturally-occurring elements over a relatively wide concentration range. Elements not occurring naturally were spiked into each solid waste, and subsequently digested with nitric acid and hydrogen peroxide, refluxed with nitric or hydrochloric acid, and analyzed by atomic absorption - direct aspiration. The resulting data were analyzed using USEPA computer program Interlaboratory Method Validation Study. The data analysis produced measures of precision and mean recovery for the acid digestion/AA direct aspiration for each element.