OCULAR EFFECTS OF EXPOSURE TO TRIETHYLAMINE IN THE SAND CORE COLD BOXOF A FOUNDRY

Objectives-To assess the acute and chronic ophthalmological effects of triethylamine exposure among foundry workers. Methods-Ocular effects on people currently, previously, and never exposed to triethylamine in a foundry cold box were studied at two points in time. The initial ph ase included an ocular examination with a slit lamp to assess corneal health, a visual acuity test, and a questionnaire to assess vision sym ptoms. The follow up included measurements of corneal thickness with a n ultrasonic pachymeter and the vision symptoms questionnaire before a nd after the shift and at the beginning and end of the week. Personal air measurements for triethylamine were also obtained during the follo w up. Results-The vision symptoms of blurriness, halos around lights, and blue hazy vision occurred more often in currently exposed workers than those previously or never exposed to triethylamine. Air concentra tions of triethylamine ranged from < 0.33 mg/m(3) to 20.3 mg/m(3). Amo ng currently exposed workers, symptoms were more common among those wi th exposure to > 10 mg/m(3) of triethylamine (odds ratio (OR) = 3.0, 9 5% confidence interval (95% CI) 0.35-25.6). No differences in corneal thickness were found in currently or previously exposed workers and th ose never exposed. No increase in corneal thickness was found after up silon before the shift. Conclusion-Despite low concentrations of triet hylamine and no corneal oedema, workers exposed to triethylamine repor ted vision symptoms. Possible explanations for these symptoms without corneal oedema are that triethylamine affects ciliary muscle function or that the corneal oedema was transient and not present when corneal thickness measurements were taken. No chronic effects were found in pr eviously exposed workers. Further research is needed to elucidate the mechanism for the reported vision symptoms, which occurred below the c urrent United States eight hour time weighted standard of 100 mg/m(3) and the American Conference of Governmental Industrial Hygienists (ACG IH) recommended value at the time of our study of 40 mg/m3. We recomme nded that air concentrations be maintained to meet the current recomme nded ACGIH threshold of 4.1 mg/m3.