The health hazards of tertiary amine catalysts used in foundry and polyurethane foam manufacturing processes were reviewed and discussed. In foundries, tertiary amine catalysts have been used in the core making processes to increase the rate of reaction between phenolic resins and isocyanates. In polyurethane foam making processes, tertiary amine catalysts have been used to control the rate of reaction of polyfunctional isocyanates and hydroxyl containing polymers. Chemical parameters discussed included the basic and nucleophilic properties of the amines and their aqueous and lipid solubilities. General toxicological effects included corrosive action on the skin and mucous membranes and systemic complaints including headache, nausea, faintness, anxiety, tachycardia, itching, erythema, urticaria, and edema. Specific visual effects included corneal edema, misty vision, halo vision, and blue or grey vision with haziness. Experimental investigations have been conducted on mechanisms underlying the visual and systemic effects of tertiary amine exposure, included mydriasis and cylcoplegia due to effects on the innervation of the sphincter muscle of the iris, edema and rupture of the corneal epithelium, blockade of parasympathetic and sympathetic ganglia, and histamine release.