Effect of process parameters upon the dopamine and lipid peroxidation activity of selected MIG welding fumes as a marker of potential neurotoxicity

There is growing concern over the neurotoxic effects of chronic occupationa l exposure to metal fume produced by welding. Elevated iron and manganese l evels in the brain have been linked to an increase in lipid peroxidation, d opamine depletion and predisposition to the development of a Parkinson's ty pe condition in advanced cases. Chemical and toxicological analysis of sele cted welding fumes, generated by model processes, were used in order to eva luate their potential to release solutes that promote oxidation of dopamine and peroxidation of brain lipids in cell free assays, This study compared the effect of shield gas, electrode type and voltage/currect upon the dopam ine and brain lipid peroxidation potential of selected welding fume, obtain ed from metal inert gas (MIG) welding systems, Overall, fume extracts were found to enhance dopamine oxidation and inhibit lipid peroxidation. Signifi cant differences were also found in the oxidising potential of fume generat ed under differing process conditions; it may therefore be possible to dete rmine the potential neurotoxicity of fumes using this system. (C) 2001 Brit ish Occupational Hygiene Society. Published by Elsevier Science Ltd. All ri ghts reserved.