The results obtained for contaminant detection in water, with the recently implemented LIES technique, are presented. A Q-Switched Nd-YAG laser (1,06 mu m) was used, focusing its output on the sample. Two experimental set- ups are used; in the first spark was generated in the bulk of the liquid, while in the second it wars generated at its surface, We: found the latter useful because it gave more information on several ionic elements present in the aqueous solution. The linearity of the system and its limits of detection were checked with know concentrations of Mg, Ca and Na.