N-hexane maculopathy in industrial workers.

A neuro-ophthalmologic examination, including fluorescein angiography and colour discrimination tests, was made of 15 workers (age range 30--65 years, mean 45.8 years) exposed to n-hexane (range of exposure 5--21 years) during vegetable oil extracting and adhesive bandage manufacturing. Visual acuity, visual fields, intraocular pressure, and biomicroscopical findings were normal. Ophthalmocopy revealed delicate macular changes in 11 or the 15 subjects. One subject had a history of central serous retinopathy in one eye. The macular changes consisted of an orange-like ophthalmoscopic appearance and a decreased macular lustre. Subtle defects of the pigment layer were present in the fluorescein angiography. Defective colour discrimination was found in 12 of the 15 subjects, one of whom had congenital deuteranopia. Colour defects were of the acquired type, mainly in the blue-yellow spectrum. Damage to the receptor lipids is suggested as the pathomechanism of the maculopathy found in this study.