The shaking in Jeffrey Tamraz’s right hand began in 2001. It was intermittent, so he paid it little mind. A six-foot, 260-pound bear of a man, he’d played football and thrown shot and discus in high school; later he got into competitive weightlifting, and worked up to bench-pressing 465 pounds — once, to win a bet, he flipped a Honda Civic on its side. He brought the same passion to his work. “I taught welding for six years,” he says. “I read books on welding. I loved to weld.”
But by 2004, the twitching had grown too persistent to ignore, and the 47-year-old felt sluggish and clumsy. He consulted a neurologist and was stunned to get the diagnosis: parkinsonism. Upon learning that his patient had been welding for 25 years, and knowing that welding fumes contain manganese, a toxic metal, the specialist suggested the symptoms were work related...cont'd
http://projects.publicintegrity.org/Manganese/Default.htmParkinsonism:
http://en.wikipedia.org/wiki/ParkinsonismParkinson's disease is one of the most common neurologic disorders of the elderly. The term "parkinsonism" refers to any condition that causes any combination of the types of movement abnormalities seen in Parkinson's disease by damaging or destroying dopamine neurons in a certain area of the brain.
Secondary parkinsonism may be caused by disorders such as a stroke, encephalitis, or meningitis. Other neurodegenerative disorders such as progressive supranuclear palsy, corticobasal degeneration, and multiple systems atrophy can also damage the dopamine neurons and produce this condition.
Medications including antipsychotics such as haloperidol, metoclopramide, and phenothiazine medications are another common cause of secondary parkinsonism.
Less frequently, exposure to overdoses of narcotics or brain damage caused by anesthesia agents (such as during surgery); exposure to toxins, and carbon monoxide poisoning can cause secondary parkinsonism if they damage the brain area that contains the dopamine neurons...cont'd
http://www.healthcentral.com/ency/408/000759.html