Focal epilepsy and exposure to organic solvents: a case-referent study.

Organic solvent exposure was studied in 104 cases of idiopathic focal epilepsy and 312 matched referents. Exposure to solvents was classified as O, I, II, or III on the basis of occupational codes. The relative risk (RR) of epilepsy for those in exposure class I, II, or III, relative to O, was estimated using conditional logistic regression. An increasing trend in RR was observed with higher exposure classes. The attributable risk for cases with focal epilepsy of deep hemispherical origin was estimated to be 8%.