Abstract: A new method for the determination of multiple elements in edible mushroom oil with direct injection by inductively coupled plasma mass spectrometry (ICP-MS) was established. Samples were diluted using kerosene, as it has some useful characteristics such as lower saturated vapor pressure and better thermal stability, and thus narrow injector torch and high temperature plasma were used to ensure good determination of the elements with low ionization efficiency and maintain the stability of the plasma torch. The collision reaction cell (CRC) method was adopted to eliminate the background signals caused by polyatomic ion interferences from organic matrix. An optional gas flow of 20% O2 in Ar was added to the carrier gas to prevent carbon build up on the interface cones. The results showed that the limits of detection (LODs) of the method were in the range of 0.018–92.27 ng/g for 26 elements. Its linear correlation was preferable with a correlation coefficient of no less than 0.999 8. The precision expressed as relative standard deviation (RSD, n = 11) was no greater than 4.4%, and the recoveries of the analytes were in the range of 92.60%–106.16%. This method was simple and applicable for the quality control and safety evaluation of inorganic elements in different edible mushroom oils.

Key words: edible mushrooms oil, kerosene, inductively coupled plasma-mass spectrometry, direct injection, elements