Development and validation of an SPE HG-AAS method for determination of inorganic arsenic in samples of marine origin

Abstract

The present paper describes a novel method for the quantitative determination of inorganic arsenic (iAs) in food and feed of marine origin. The samples were subjected to microwave-assisted extraction using diluted hydrochloric acid and hydrogen peroxide, which solubilised the analytes and oxidised arsenite (As(III)) to arsenate (As(V)). Subsequently, a pH buffering of the sample extract at pH 6 enabled selective elution of As(V) from a strong anion exchange solid-phase extraction (SPE) cartridge. Hydride generation atomic absorption spectrometry (HG-AAS) was applied to quantify the concentration of iAs (sum of As(III) and As(V)) as the total arsenic (As) in the SPE eluate. The results of the in-house validation showed that mean recoveries of 101-104% were achieved for samples spiked with iAs at 0.5, 1.0 and 1.5 mg·kg(-1), respectively. The limit of detection was 0.08 mg kg(-1), and the repeatability (RSD(r)) and intra-laboratory reproducibility (RSD(IR)) were less than 8% and 13%, respectively, for samples containing 0.2 to 1.5 mg kg(-1) iAs. The trueness of the SPE HG-AAS method was verified by confirming results obtained by parallel analysis using high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry. It was demonstrated that the two sets of results were not significantly different (P < 0.05). The SPE HG-AAS method was applied to 20 marine food and feed samples, and concentrations of up to 0.14 mg kg(-1) of iAs were detected.

Effects of industrial processing on essential elements and regulated and emerging contaminant levels in seafood

“…Inorganic arsenic (iAs) by anion exchange HPLC (High Performance Liquid Chromatography) coupled on-line to the ICP-MS. Determination of inorganic arsenic (iAs) followed the standard (EN 16802:2016) issued by European Committee for Standardization (CEN, 2016) and hydrogen peroxide ensured a quantitative oxidation of arsenite (iAs III ) to arsenate (iAs V ) (Rasmussen et al, 2012). For method details see supplementary material "1.2 Chemical analysis".…”

“…Subsamples (1.0 g ww prawn and fish 0.2 g dm CRM) were extracted by 10 mL (aqueous 0.1 M nitric acid, 3% hydrogen peroxide) at 90ºC for 1 hour and centrifuged (2,500×g, 10 °C) for 10 min. Hydrogen peroxide ensured a quantitative oxidation of arsenite (iAs III ) to arsenate (iAs V ) (Rasmussen et al, 2012). Aliquot of the supernatant was removed for arsenic speciation analysis.…”

Analysis of Main Arsenic Species in Canned Fish Marketed in the Czech Republic and Austria

“…This problem is frequently solved by analysis of the sum of As(III) and As(V) instead of individual species. Therefore, in some procedures, As(III) is converted to As(V) by oxidation with hydrogen peroxide prior to chromatographic analysis (see [17,18] for fish tissue analysis, [19] for analysis of urine or [20] for analysis of blood). The other species of arsenic MA, DMA, and As(V) are separated with very good resolution.…”

Determination of Inorganic Arsenic in a Wide Range of Food Matrices using Hydride Generation - Atomic Absorption Spectrometry.

“…This method which proved to be fit for analyzing iAs in feed could lack the sensitivity required to determine iAs in food of non-marine origin, which according to EFSA seems to be the main dietary contributors in Europe 3 . However, the same group that developed and validated EN 16278:2012 tested and successfully applied and validated the method to determine iAs in seafood and rice in a collaborative trial 11 12 .…”