Quantitative determination of barium in human blood by ion chromatography: Method development and case application in barium intoxication

Abstract Barium is an alkaline earth metal widely used in various industrial applications and as a rodenticide. Barium poisoning primarily occurs through occupational exposure or deliberate ingestion. Water‐soluble barium compounds, such as barium chloride and barium carbonate, can induce severe neurological, cardiovascular, and muscular toxicity. While atomic absorption spectrometry (AAS), inductively coupled plasma‐optical emission spectrometry (ICP‐OES), and inductively coupled plasma‐mass spectrometry (ICP‐MS) are commonly used for barium analysis, this study developed and validated an ion chromatography (IC)‐based method utilizing a 250 μL sample loop for the quantitative analysis of barium in blood and qualitative analysis of forensic evidence. The method was validated with a limit of detection (LOD) of 0.03 mg/L and a limit of quantification (LOQ) of 0.10 mg/L. Intra‐day and inter‐day precision (RSD) ranged from 1.9% to 5.3% and 1.8% to 5.1%, respectively. Intra‐day and inter‐day accuracy (bias) ranged from 92.1% to 98.9% and 93.2% to 97.1%, respectively, with a linearity of R 2 > 0.99. The method was successfully applied to a suicide case involving barium ingestion, where barium was detected at 1.66 mg/L in the heart blood, as well as in the gastric contents and crime scene evidence. This IC‐based approach provides a reliable alternative for barium determination in forensic toxicology.