Determination of Elements in Natural-Water Biota Sediment and Soil Samples Using Collision/Reaction Cell Inductively Coupled Plasma-Mass Spectrometry Part 1

<p>A new analytical method for the determination of elements in filtered aqueous matrices using inductively coupled plasma-mass spectrometry (ICP-MS) has been implemented at the U.S. Geological Survey National Water Quality Laboratory that uses collision/reaction cell technology to reduce molecular ion interferences. The updated method can be used to determine elements in filtered natural-water and other filtered aqueous matrices including whole-water biota sediment and soil digestates. Helium or hydrogen is used as the collision or reaction gas respectively to eliminate or substantially reduce interferences commonly resulting from sample-matrix composition. Helium is used for molecular ion interferences associated with the determination of As Co Cr Cu K Mg Na Ni V W and Zn whereas hydrogen is used for Ca Fe Se and Si. Other elements that are not affected by molecular ion interference also can be determined simply by not introducing a collision/reaction gas into the cell. Analysis time is increased by about a factor of 2 over the previous method because of the additional data acquisition time in the hydrogen and helium modes. Method detection limits for As Ca Co Cr Cu Fe K Mg Na Ni Se Si (as SiO2) V W and Zn all of which use a collision/reaction gas are 0.06 microgram per liter (?g/L) As 0.04 milligram per liter (mg/L) Ca 0.02 ?g/L Co 0.02 ?g/L Cr 0.04 ?g/L Cu 1 ?g/L Fe 0.007 mg/L K 0.009 mg/L Mg 0.09 mg/L Na 0.05 ?g/L Ni 0.04 ?g/L Se 0.03 mg/L SiO2 0.05 ?g/L V 0.03 ?g/L W and 0.04 ?g/L Zn. Most method detection limits are lower or relatively unchanged compared to earlier methods except for Co K Mg Ni SiO2 and Tl which are less than a factor of 2 higher. Percentage bias for samples spiked at about one-third and two-thirds of the concentration of the highest calibration standard ranged from -8.1 to 7.9 percent for reagent water -14 to 21 percent for surface water and -16 to 16 percent for ground water. The percen</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p><br>