Simultaneous Determination of Water- and Fat-Soluble Arsenic Species by HPLC-ICP-MS in Food Samples: A Pilot Study

Arsenic is a highly toxic element that occurs naturally and widely in the environment. Its toxicity depends on the forms in which it occurs, with inorganic arsenic species considered more toxic than organic ones. However, besides the commonly analyzed arsenic species [As(III), As(V), AsB, DMA, and MMA], there are also fat-soluble organic species, arsenolipids, which can be as toxic as or even more toxic than inorganic species. Therefore, to accurately assess the health risks resulting from the consumption of foods containing arsenic, a speciation analysis is needed. Taking this into account, the study aimed to develop a method for the simultaneous determination of both water-soluble [As(III), As(V), DMA, and AsB] and fat-soluble (AsHC 360 and AsFA 362) arsenic species using HPLC-ICP-MS. The present study reports the results of a preliminary optimization investigation. The method development and analyses were conducted qualitatively using standards and food samples—algae, salmon and tuna. The developed method allowed for the full separation of arsenolipids and the partial separation of water-soluble arsenic species in a single run. As there are no commercially available arsenolipid standards, the syntheses of AsHC 360 and AsFA 362 were also a part of the study. Additionally, the synthesized arsenolipids were analyzed by LC-MS.