Four cases of progressive supranuclear palsy in patients exposed to organic solvents.

Four cases are described in which Progressive Supranuclear Palsy (PSP) is associated with the use of organic solvents. Two of them are a housewife and an exbanker who had multiple exposure to insecticides (with organic solvent base), followed years later with a diagnosis of PSP. The other two are of lithographers, both of whom worked at the same industrial firm where solvent exposure took place with subsequent development of PSP. The hypothesis that PSP is linked to an environmental toxin is supported by these cases.