Determination of Mercury and Other Metals in Red Yeast Rice

Chromium, arsenic, cadmium, nickel, selenium, mercury and lead have been determined in red yeast rice samples by ICP-MS and a Hydra-C mercury analyzer. Less than 0.010 μg/g mercury was found in all but one sample, which had 0.011 μg/g. The amounts of chromium, arsenic, cadmium, nickel, selenium, cadmium and lead varied from 0.05–0.83 (Cr), 0.05–0.35 (As), 0.004–0.139 (Cd), 0.13–2.05 (Ni), 0.028–0.222 (Se), and 0.000–0.517 (Pb) μg/g. Percent recoveries of spiked samples ranged from 77 – 111%. Recoveries of mercury in two different standard reference materials were 83 and 110%. The minimum detection limit and limit of quantitation for mercury were 0.2 and 1.0 ng, respectively.