Dear Alvis: The search should go on for such environmental factors. When I was trained in public health research, the approach in epidemiology was to look for clusters of cases. One never expected to find a 100 % correlation between the presence of a causative agent and development of cases. There is consider- able variation to susceptibility. Since this is not an infectious disease, I would expect that we are looking for patterns of agents that could interfere with the functioning of the the substantia nigra. I suspect that lots of different clusterings will be found. We shouldn't lose heart, but keep the search going. What would be helpful would be some research group being willing to keep a database going that would hold all the descriptive findings--of the clusterings of enviornmental factors, and of the patient characteristics that might go along with that. Jace, I hope that when the genetic aspects of this are found, that they then tell us to cure ourselves or say, sorry about that. I agree that culturally it is easiest to blame messengers and victims. I fit in at least two of the current categories of "exposure." I had exposure to farm pesticides, fertilizers, etc., and to photographic solutions as a photographer. Probably more. This is where the detective process involved in epidemiology gets both complicated and interesting. Keep us posted, Alvis. Bob N.