NMR-based metabolomics: novel application in exposomics

Introduction: Metabolomics studies the end products of biological processes ocurring in living systems, based on the quantification of low molecular weight molecules in a specific biofluid to evaluate the changes in metabolism due to endogenous and/or exogenous stimuli. Nuclear magnetic resonance (NMR) has proven to be a very valuable analytical platform for its ability to quali-quantitatively characterize complex mixtures with minimal pretreatment and can be applied in the field of occupational medicine. Methods: Urine samples of exposed workers and healthy nonexposed volunteers were collected from different biolmonitoring campaigns and analyzed by nuclear magnetic resonance (NMR) spectroscopy with mono and bidimensional experiments Results: About 40 metabolites, including amino acids, organic acids, aromatic compounds and alcohols, were identified and quantified. It was also possible to identify and quantify both metabolites and dose biomarkers such as mandelic and phenilglyossilc acids in case of styrene exposure. Discussion: By comparing the urinary metabolites of exposed and non-exposed it is possible to observe quantitative differences validated by univariate and multivariate statistical analysis. These differences may be attributable to metabolic alterations at a subclinical level and therefore provide indications on potential variations to be followed over time to predict the onset of occupational disease. Conclusion: The application of NMR metabolomic approach in occupational medicine evidence a characteristic metabolic profile by identyfing early biomarkers of effect and their involvement in the metabolic pathway.