Several studies have demonstrated the influence of parameters and shielding gas on metal transfer stability or on the generation of fumes in MIG/MAG welding, but little or nothing has been discussed regarding the emission of toxic and asphyxiating gases, particularly as it pertains to parameterization of the process. The purpose of this study was to analyze and evaluate the effect of manufacturing aspects of welding processes (short-circuit metal transfer stability and shielding gas composition) on the gas emission levels during MIG/MAG welding (occupational health and environmental aspects). Using mixtures of Argon with CO2 and O2 and maintaining the same average current and the same weld bead volume, short-circuit welding was performed with carbon steel welding wire in open (welder’s breathing zone) and confined environments. The welding voltage was adjusted to gradually vary the transfer stability. It was found that the richer the composition of the shielding gas is in CO2, the more CO and CO2 are generated by the arc. However, unlike fume emission, voltage and transfer stability had no effect on the generation of these gases. It was also found that despite the large quantity of CO and CO2 emitted by the arc, especially when using pure CO2 shielding gas, there was no high level residual concentration of CO and CO2 in or near the worker’s breathing zone, even in confined work cells.
Context: Moringa oleifera leaves are renowned for their health-promoting benefits, particularly when incorporated into the diet. Objective: This study aimed to evaluate the protective effects of a Moringa oleifera-based diet against nickel (Ni)-induced hepatotoxicity in rats. Methods: Male rats were divided into six groups, receiving oral administration of 20 mg/kg body weight nickel sulfate in normal saline while being fed either a normal diet or Moringa oleifera-based diets over a 21-day period. Post-treatment, all animals were sacrificed under anesthesia 24 hours after the final administration. Results: Ni exposure significantly increased plasma activities of ALT, AST, and ALP, and altered lipid profiles, indicated by elevated TAG, CHOL, and LDL-C levels, and decreased HDL-C concentration. Additionally, Ni exposure increased plasma MDA levels and decreased GSH concentrations. Histopathological analysis revealed inflammation and cellular degeneration in the liver due to Ni exposure. Notably, the M. oleifera-based diet demonstrated hepatoprotective effects, evident from improved liver function indices, restored lipid profiles, and ameliorated cellular architecture. Conclusion: The findings support the health-promoting value of M. oleifera, highlighting its potential to mitigate hepatic injuries induced by toxic metal exposure.