Direct Measurement of Trace Metals in Edible Oils by 7500cx ICP-MS with

A simple methodology for the measurement of trace and ultratrace metals in edible oils is described. A selection of seed, olive, and nut oils were measured with a spike recovery being performed on a rapeseed oil – recoveries of between 94 % (Ag) and 107 % (Sn) were achieved. Each sample was analyzed directly using an Agilent 7500cx ICP-MS with Octopole Reaction System (ORS) technology following a simple 3x dilu-tion in kerosene. The ORS is used to remove plasma- and matrix-based interferences within a single acquisition, greatly improving the detection limit performance for the interfered-with elements, such as Cr, Fe, and Mg. The detection limits (DLs) and back-ground equivalent concentrations (BECs) were in the µg/kg (ppb) to ng/kg (ppt) range for all elements. An 8-hour stability run on a spiked (~12 µg/kg) rapeseed oil was performed and precision was found to be approximately 2 % RSD for all elements except Na (4%), which was partially influenced by contamination