To decipher the complex reactions controlling the bioavailability of heavy metals in soils, one of the important tasks is the understanding of the key reactions and factors that determine the speciation and spatial distribution of heavy metals in soils and the acquisition and translocation of heavy metals in plants. Thus, this proposed study aims at developing LA-ICP-MS method in conjunction with µ-XRF and µ-XAS methods for determining the speciation and spatial distribution of heavy metals in soils and plants. As, Cd, Cu and Zn were analyzed on soil and plant samples and certified materials. The results of As, Cd and Zn obtained by LA-ICP-MS were shown to be comparable to the counterparts of solution ICP-MS analysis in terms of accuracy and precision. To further improve the performance of the method, different quantitation strategies were employed. The results revealed that the appropriate selection of internal standard can improve the analytical performance of the method. Meanwhile, the good reproducibility of the LA-ICP-MS method indicates the feasibility of applying the method in determining the spatial distribution of heavy metals in soil and plant samples, which was demonstrated on rice grain and rhizosphere soil samples. The synergetic application of the LA-ICP-MS and synchrotron-based µ-XRF and µ-XAS methods provides the possibility in observing the distribution and transformation of metals within a heterogeneous sample, such as soils and plants, and at soil-plant root interfaces. The information will advance our understanding of the key processes that determine the bioavailability and toxicity of heavy metals in soils and their transformation within the plants after metals are absorbed by the plants.

Heavy metals,Laser ablation inductively coupled plasma mass spectrometry, Elemental mapping