The analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). At 280 °C and 160 bar, the optimal condition for microwave-assisted wet digestion in a single reaction chamber was achieved with a mixture consisting of 3 mL of 0.1 mol L−1 HNO3 and 5 mL of 30% H2O2 (0.25 g rice sample)