A XeCl laser and a Q-switched Nd:YAG laser operating at 1064, 532, 355 and 266 nm were used to ablate brass materials with varying concentrations of Zn and Cu. The ablated material was transported to an inductively coupled plasma for further atomization, excitation and ionization with an atomic emission spectrometric detection. A Zn enhancement was observed, which could be suppressed by using a Nd:YAG laser working at 266 nm with fluences higher than 400 J cm(-2) (equivalent to 80 GW cm(-2)). In contrast, a lack of linearity was observed for Cu as a function of the concentration, regardless of the wavelength and the fluence. The Cu problem seemed to occur during the ablation and was related to the structure of the brass material. Lack of linearity was also observed for Zn and other contained elements when samples from different origins were used. (C) 1998 Elsevier Science B.V.