Simultaneous multielemental determination:

In case of ICP-AES all the elements get excited at the same time in the plasma torch. The radiation emitted by them can be measured sequentially or simultaneously.   Hence it is easier to determine several elements simultaneously. Therefore, in case of AAS a line source hollow cathode lamp is used as the radiation source. As just one analyte element is able to absorb the radiation emitted by the cathode lamp we can measure only one element at a time. For multielemental determination by AAS we need to use a cathode lamp for each element thus making it a difficult task.