Gull eggs are excellent bioindicators of environmental pollution as reflect the contamination levels of coastal areas, especially of persistent and bioacumulative compounds such as perfluoroalkyl substances (PFAS). This study aims to evaluate the geographical distribution and 10-year temporal trends (2009-2018) of 17 PFAS in eggs of two gull species (Larus michahellis and Larus audouinii) from 5 main Spanish colonies. ∑PFAS ranged from 13.
View Article and Find Full Text PDFNeuro-active pharmaceuticals have been reported to act as endocrine disruptors enhancing reproduction in the model crustacean Daphnia manga at environmental concentrations of ng/L. Oxylipins and more specifically eicosanoids, which are lipid mediators formed from polyunsaturated fatty acids (PUFAs), are known to regulate reproduction together with other physiological processes in insects. In D.
View Article and Find Full Text PDFThe performances of gas chromatography with mass spectrometry and of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry are examined through the comparison of Daphnia magna metabolic profiles. Gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with mass spectrometry were used to compare the concentration changes of metabolites under saline conditions. In this regard, a chemometric strategy based on wavelet compression and multivariate curve resolution-alternating least squares is used to compare the performances of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry for the untargeted metabolic profiling of Daphnia magna in control and salinity-exposed samples.
View Article and Find Full Text PDFMetabolic changes of Daphnia magna pools due different abiotic factors linked to global climate change (salinity, temperature and hypoxia) were investigated using untargeted GC-MS and advanced chemometric strategies using a three factors two-level full factorial experimental design (DoE). Effects of these three factors and identity of the metabolites whose concentrations changed because of them were investigated. The simultaneous analysis of GC-MS data sets using Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) allowed the resolution of the elution and mass spectra profiles of a large number of D.
View Article and Find Full Text PDFComprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS) is a powerful tool for separation and identification of analytes in complex natural samples. In this paper, different chemometric methods were compared for fast non-targeted GC×GC-TOFMS metabolomic profiling of the crustaceous species Daphnia magna and a general chemometric strategy and workflow is proposed. The strategy proposed in this work combined the compression of GC×GC-TOFMS data matrices in the retention time direction using wavelets and the appropriate column-wise data matrix augmentation arrangement, and its modeling by Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS).
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