Determination of Arsenic Species in Fruit Juice and Fruit Drink Products Using Ion Pair Chromatography Coupled to Inductively Coupled Plasma Mass Spectrometry

Abstract

Ion-pair chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) was evaluated and validated for the determination of arsenic species in fruit juice and fruit drink products. A Phenomenex analytical column (Prodigy 3 μ ODS (3) 4 μm × 2.0 mm × 150 mm) and a mobile phase consisting of 5 mmol l⁻¹ malonic acid, 3 mmol l⁻¹ of tetrabutylammonium hydroxide solution and 5 % methanol were used to achieve arsenic speciation separation. The arsenic species were detected at m/z 75 with an Agilent 7500cx ICP-MS. After demonstrating the method was sensitive, accurate and fit for purpose, and it was applied to analyze 96 fruit juice and fruit drink samples. Speciation analysis of the 96 fruit juice and fruit drink products revealed that inorganic arsenic was the major species found in the majority of juice products tested in the study. The concentration of inorganic arsenic (sum of As³⁺ and As⁵⁺) ranged from<limit of quantification (LOQ) to 23.9 μg l⁻¹, with a mean value of 3.57 ± 4.42 μg l⁻¹. Dimethylarsenate (DMA) was found in 32 of the samples, and the mean value is 0.30 ± 0.55 μg l⁻¹. Monomethylarsenate (MMA) was found in 26 of the samples, and the mean value is 0.30 ± 0.71 μg l⁻¹.