The following are references documenting a connection between Parkinson's
and mercury from my paper on health effects.  There are also other
references relative to autoimmune problems in general that are also
relevant.  Mercury affects all such it seems, depending on the vulnerability
of the specific person. The paper can be found at Jeff Clark's homepage or
through Dagfinn's homepage.
Bernie

(98) A. Seidler et al, "Possible environmental factors for Parkinson's
disease",Neurology 46(5):1275-1284, 1996;  &  F.O.Vroom et al,
"Mercury vapor intoxication",  Brain 95: 305-318, 1972; &
Ohlson et al, "Parkinsons Disease and Occupational Exposure to
Mercury", Scand J. Of Work Environment Health, Vol7, No.4: 252-256, 1981..

(169) C.H.Ngim et al, Neuroepidemiology,"Epidemiologic study on the             
ssociation between body burden mercury level and idiopathic Parkinson's
disease",  1989, 8(3):128-41.

(248) Y.Finkelstein et al, "The enigma of parkinsonism in chronic borderline
mercury intoxication, resolved by challenge with penicillamine.
Neurotoxicology, 1996, Spring, 17(1): 291-5.