Isotopic investigations in groundwater by inductively coupled plasma mass spectrometry

Abstract

For many decades, the accurate and precise determination of isotope ratio has remained a very strong interest to many researchers due to its important applications in environmental, geological, biological, archeological, and medical sciences. Isotope analysis of groundwater intended for human consumption can provide valuable information on the processes of transfer of elements within environmental compartments, as well as on the assessment of anthropogenic influences in the environment, which may impair the quality of drinkable water. However, precise and accurate measurements of isotope ratios can be quite challenging and require (i) some practical knowledge regarding, for example, sample preparation and mass bias correction, and (ii) appropriate instrumentation based on multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The aim of the proposed research project is to develop an analytical method for the determination of rare earth elements (REE) isotope ratio in groundwater by MC-ICP-MS. REE constitute useful environmental tracers and have been used as indicators of anthropogenic pollutants in natural waters. Preliminary experiments will be performed with a composite sample in order to define the most appropriate isotope(s) pair(s) and sample preparation strategy. The MC-ICP-MS operational conditions and mass bias correction approaches will be also optimized investigated. Groundwater samples collected alongside Sao Paulo State, Brazil will be then analyzed by the proposed method, and data on REE isotopic variation will be considered for the evaluation of natural and anthropogenic influences within these water reservoirs.