259 Investigating welding fume exposure in professional welders using biomonitoring and metabolomics approaches

Abstract We aimed to investigate the health effects attributed to welding fume exposure in professional welders using biomonitoring and metabolomics approaches. The cohort included 38 welders as the case group and 36 electricians as the control group, recruited from various facilities across the province of Alberta, Canada. Air sampling was performed throughout the work shift. Fasting urine samples were collected from the welders and controls. The identification of metals and metabolites in the samples was performed using Inductively Coupled Plasma Mass Spectrometry (ICP/MS) and Liquid Chromatography with Tandem Mass Spectrometry (LC-MS-MS), respectively. Data analyses were conducted using STATA version 19.0 and MetaboAnalyst version 5.0. Significantly higher levels of As, Cd, Cr, Fe, Mn, and Ni were observed in the urine of welders compared to controls (p 0.05). Regarding the metabolomics profile, we identified 92 metabolites in the urine samples of the studied groups. Multivariate receiver operating characteristic (ROC) curve analysis identified metabolites, such as beta-hydroxybutyric acid, asparagine, ornithine, choline, propionic acid, and histidine, as biomarkers for welding fume exposure (AUC 0.7). These metabolites exhibited significantly higher levels in welders than in controls. In addition, our findings suggest that smoking, welding experience, respirator usage, and age significantly affect the concentrations of certain urinary metabolites in professional welders. Our study highlights the potential benefits of using biomonitoring and metabolomics approaches to investigate the adverse health effects of welding fume exposure. However, we recommend further investigations to explore the underlying mechanisms of these associations and the effects of other factors. Keywords: Biomonitoring, Exposure assessment, Welding fumes, Metabolomics.