Quantitative Determination of Arsenic Species from Fruit Juices Using Acidic Extraction with HPLC-ICPMS

Abstract

Throughout the US Food and Drug Administration’s routine monitoring of various juice samples for elemental contaminants, a limited number of samples exhibited unexpected behavior related to the arsenic content. Juice samples were subjected to total arsenic determination and those containing arsenic > 10 μg kg −1 were subjected to arsenic speciation analysis using FDA Elemental Analysis Manual (EAM) 4.10 method (AOAC First Action Method 2016.04) to determine the concentration of iAs and other common organic arsenicals. For a subset of samples, the sum of the arsenic species was significantly less than the total arsenic value (i.e., mass balance < 65%), which is uncommon for a liquid-based matrix. Juice types that have exhibited this behavior include pomegranate, prune, and cherry juices. Causes for this issue were explored which ultimately led to an alternate sample preparation technique, extraction with 0.28 M HNO 3 along with heat, which resulted in drastically improved mass balances approaching 100%. The method proved robust, with both accurate and precise measurements for multiple juice samples analyzed by a total of four laboratories. Two laboratories performed a level 3 multilaboratory validation. This work discusses various issues that were encountered, attempts to determine the source of the problem, the eventual solution in the form of a modified extraction procedure, and the multilaboratory validation results.

Atomic spectrometry update: review of advances in elemental speciation

“…In a third publication from the US Food and Drug Administration’s team, various issues encountered in the determination of As in fruit juice are discussed and a solution using a modified extraction procedure reported. 46 Juice samples were subjected to total As determination and those containing As >10 μg kg −1 were subjected to As speciation analysis using FDA Elemental Analysis Manual (EAM) 4.10 method (AOAC First Action Method 2016.04), basically a MAE followed by HPLC-ICP-MS analysis, to determine the concentration of iAs and other common organic As species. For a subset of samples, the sum of the As species was significantly less than the total As value ( i.e.…”

Green and Simple Extraction of Arsenic Species from Rice Flour Using a Novel Ultrasound-Assisted Enzymatic Hydrolysis Method

“…The studies of arsenic speciation analysis have grown rapidly in recent years and are generally conducted using high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICPMS) [12][13][14][15][16]. Prior to that, speciation analysis usually requires the extraction of the species from complex matrices into solvents before they can be identified and measured.…”