Interferences of matrix elements in trace-element anal. by inductively coupled plasma mass spectrometry are reviewed and discussed using results of steel anal. with the PE Elan 500 app. The effect of compromise or optimized measurement conditions on the accuracy and detn. limit is shown on B detn. in steel. The suppression of signal intensity by high concns. of matrix elements (Fe) and spectral overlap by multiat. ions are documented on the detn. of (1) B, Mg, Al, Ti, and Cr and (2) Mn, resp.