Application of laser ablation inductively coupled mass spectrometry (LA-ICP-MS) for the determination of major, minor, and trace elements in bark samples

The large surface area of barks from many tree species enables the effectiv e accumulation of pollutants. Therefore, the analysis of bark material will provide useful information about the degree of pollution of a certain regi on. The determination of main, minor, and trace elements (Al, Ca, Cd, Ce, C r, Cu, Fe, Mn, P, Pb, S, Ti and Zn) in bark was performed with an Nd:YAG la ser coupled to an ICP-MS system. Bark standards for the calibration by lase r ablation ICP-MS were prepared from different bark layers which differ for some relevant elements in concentrations. Four digestion procedures for th e decomposition of the standard pellets, the numbers of laser shots per sam ple and of samples per region necessary have been investigated. Representat ive results were obtained for 5 or more samples taken from different indivi duals of one species of a sampling area and the averaged element concentrat ions of 10 separately placed laser shots for each sample. Laser ablation IC P-MS was applied for the characterization of real bark samples from differe nt regions with high and low pollution burden. It was shown that the method is well suited to characterize different degrees of environmental impact. Anthropogenic sources were responsible for the higher concentrations of mos t of the elements under investigation.