Exploring complementary analytical techniques for environmental analysis of glacial lakes in the Pyrenees Mountains.

Glacial lakes are fragile ecosystems, and many of them are susceptible to pollution. This study assesses the potential anthropogenic impact on these lakes through sediment analysis. Sediment samples were collected (Spring 2023) in the Aragonese Pyrenees Mountain range and characterized using complementary analytical techniques: LIBS (Laser Induced Breakdown Spectroscopy, XRD (X-ray diffraction), ICP-MS (Inductively Coupled Plasma-Mass Spectrometry), and FESEM-EDS (Field Emission Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy). These methods were selected for their specific strengths and complementarity in providing elemental, mineralogical, and morphological data. Major elements were identified using LIBS, while quantitative analysis was performed by ICP-MS. XRD and FESEM-EDS were employed for studying the crystalline structure of the samples and individual particles, respectively. Multivariate statistical analysis revealed enrichment of As and Pb in some samples, presenting potential risks to aquatic ecosystems. These findings highlight the need for continuous monitoring of heavy metals and demonstrate the importance of using different analytical techniques to achieve an accurate and complete characterization of glacial lake samples.