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Memorandum Regarding Use of Hydrochloric Acid (HCl) in Digests for Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) Analysis

This memorandum clarifies which version of Method 3050 to use based on the analysis technique. If inductively coupled plasma – atomic emission spectroscopy (ICP-AES) is used, HCl should be used in the acid digestion, following Method 3050A. If ICP-MS is used, no HCl should be used due to matrix interference, following Method 3050B. The memorandum also discusses the detection of silver and antimony by ICP-MS.

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