Matrix Extension and Multilaboratory Validation of Arsenic Speciation Method EAM §4.10 to Include Wine

A multilaboratory validation (MLV) was performed to extend the U.S. Food and Drug Administration's (FDA) analytical method Elemental Analysis Manual (EAM) §4.10, High Performance Liquid Chromatography-Inductively Coupled Plasma-Mass Spectrometric Determination of Four Arsenic Species in Fruit Juice, to include wine. Several method modifications were examined to optimize the method for the analysis of dimethylarsinic acid, monomethylarsonic acid, arsenate (AsV), and arsenite (AsIII) in various wine matrices with a range of ethanol concentrations by liquid chromatography-inductively coupled plasma-mass spectrometry. The optimized method was used for the analysis of five wines of different classifications (red, white, sparkling, rosé, and fortified) by three laboratories. Additionally, the samples were fortified in duplicate at levels of approximately 5, 10, and 30 μg kg^-1 and analyzed by each participating laboratory. The combined average fortification recoveries of dimethylarsinic acid, monomethylarsonic acid, and inorganic arsenic (iAs the sum of AsV and AsIII) in these samples were 101, 100, and 100%, respectively. To further demonstrate the method, 46 additional wine samples were analyzed. The total As levels of all the wines analyzed in this study were between 1.0 and 38.2 μg kg^-1. The overall average mass balance based on the sum of the species recovered from the chromatographic separation compared to the total As measured was 89% with a range of 51-135%. In the 51 analyzed samples, iAs accounted for an average of 91% of the sum of the species with a range of 37-100%.