Thanks Ron,
So it appears concerns about TCE exposure should be a concern to all of us, as it is still a commonly used solvent. And though there has been some research, there have been no studies that definetly link PD with exposure to Trichloroethylene. Dr. Gash's paper miight open the door to further studies.
Those interested in environmental causes and neurotoxiic contaminants should check out the Collaborative on Health and the Environment -- Parkinson's Disease Working Group at:
http://www.healthandenvironment.org/...ups/parkinsons

It is led by Jackie Hunt Christensen, who many may know from PAN.
There is a wealth of information on this site including a database of toxic exposures and disease, and a number of documents that came out of a 2007 meeting on a Consensus Statement on Parkinson's Disease and the Environment . There is also a
"Parkinson's Disease Public Statement - What Scientists Know and Want to Know". however there is little said about TCE exposure. The document did come out before DR. Gash's study was published.

I attended the 2007 meeting, and was struck by how few definite conclusions could be mmade about environmental causes of PD. The scientists believed more research neewded to be done for nearly all possible neurotoxins. The main problems sited were lack of funding for these type of studies, and lack of PD registeries.
But for those interested in these issues, the cHE website is a good place to start.