A 40 year old is referred to you for evaluation of Parkinson's disease. He presents with dyscoordination, loss of balance, and confusion. He is on a fad diet of meat, fish, poultry, dried fruit, and nuts. He works in the steel and welding industry. He is a nonsmoker but does drink occasional alcohol. He uses marijuana as well.
Challenge: This is toxicity of the element shown above: what is it?
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