Toxicology Litigation Support

Manganese/Welding Fumes

Manganese is an essential element for normal body function but excess manganese in the body can disrupt neurotranmission in the brain causing a condition very similar if not identical to Parkinson's Disease. The neurotoxicity of manganese has been known since the mid 1800's as described in an elegant timeline which Dr. Parent has constructed of peer-reviewed literature publications and internal company documents. Industry chose to try to conceal the neurotoxicity of manganse in welding fumes as is described in the timeline.

Welding rods and various metals that are welded contain varying amounts of manganese. When an arc is struck, the welding rods and the metals melt and some metal vaporizes to form an extremely fine dust or fume which contains significant amounts of manganese. The particles that are produced and contain manganese are so small that they can be absorbed through the nasal membranes and travel within the olfactory neurons directly to the brain. Inhaled dust also deposits in the lungs and is slowly released into the bloodstream and is passed on directly to the brain by traversing the blood-brain barrier. Manganese concentrates in the globus pallidus area of the brain and you can actually see it in the brain of current welders via a specialized MRI technique. Once in the brain, manganese disrupts neurotranmission from one part of the brain to the others and this results in a multitude of symptoms but mainly a movement disorder which strongly resembles Parkinson’s Disease. The illness begins with disruption of cognitive function (anorexia, memory loss, headaches, hallucinations etc) and other neurobehavioral problems and then progressive to tremors and on to a variety of signs and symptoms relating to movement including postural instability and gait problems, among others.

Consultox has acquired over 1300 peer-reviewed literature publications and internal company documents that deal with manganese, welding fumes and parkinsonism. This resource provides a firm foundation for any additional work that Dr. Parent will be called upon to do relating to this chemical. There are many people out there who have been exposed to manganese and welding fumes in the past or are currently being exposed.

• Download a PDF of the September 2004 report