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The Inorganic Ventures team answers listener questions focused on pharmaceutical elemental impurity analysis by ICP-MS. They explain why an indium internal standard becomes unstable in high-pH matrices due to insoluble hydroxide formation and how EDTA complexation can stabilize indium when used for iodine analysis. They discuss mercury washout problems caused by volatility, adsorption to sample introduction surfaces, memory effects, and redox/speciation, and emphasize proper rinse sequencing and the roles of chloride-based rinses and specialty solutions like ICP True Rinse to prevent carryover and failed QC checks. They address poor gold recovery during heated prep due to adsorption, reduction, and volatility. Finally, they advise diluting working standards in matrices that match samples while considering element stability and compatibility in stock matrices.