Occupational Blindness from Chronic Methanol Intoxication

Abstract

Objective: To describe three patients with occupational blindness from chronic methanol intoxication.
Case presentation: Three patients who worked in the same industry of methylated spirit manufacture for more than 1 year developed bilateral visual loss from inhaled methanol intoxication. Ophthalmological, neurological examinations and blood methanol levels were undertaken. Two male and one female patients developed a sudden onset of bilateral blindness. Blood and urine methanol levels obtained from the male patients at 48 and 72 hours after their cessation to methanol exposure were negative. Those from the female patient at 9 hours after their cessation to methanol exposure were 73.78 mg/dl. Their final visual acuity was not improved after the treatment.
Conclusion: Chronic methanol intoxication from inhalation is likely to produce ocular problems with mild systemic toxicity with severe ocular problems which eventually result in permanent blindness. The risk assessment of occupational health and safety should be seriously taken into account to avoid harmful effect of hazards in the workplace.