The relationship between exposure to organic solvents and the prevalence of lens changes was studied in a group of 92 car painters and a comparison group of 92 engineers from the Finnish State Railways. Both groups were examined ophthalmologically. Among the 92 car painters, with a mean age of 34.9 years (range of 21--64 years; S.D. 10.4 years), two had been operated on for a cataract and 46 had lens changes, mainly nuclear sclerosis, clefts, lamellar separation, or cortical and subcortical opacities not affecting visual acuity. In 69 age-matched pairs, for whom the factors inducing false-positive results had been excluded, 2 car painters had more lens changes than their age-matched pairs. Lens changes occurred with increased frequency after 10 years of exposure.