Exposure of High Concentration of Methanol Vapor for Neurological Intoxication in Factory Workers

Abstract

Abstract Background A few studies of biological monitoring of MeOH vapor exposure focused on human subjects were thought to have been reported until 2000. After that until current, the study of MeOH vapor exposure concentration and neurological toxicity as the dose-response relationship for biological monitoring has not been fully studied. Objective The study aims to reasonable estimate the step-by-step methanol concentration of neurological toxicity from respiratory exposure in workers. Methods The methanol exposure was constituted to focus on respiratory air and symptoms. The previous reports were searched for dose-response relation between methanol vapor concentration and urinary methanol concentration and between methanol vapor concentration and symptoms for representative methanol exposure. Google Scholar (including Korean reports) and PubMed from 1980 to 2023 present were examined as search engines. Results Respiratory methanol exposure 93 ppm to 200 ppm of vapor concentration (TLV-TWA of ACGIH) did not show clear symptoms. And their corresponding urinary methanol showed 22 to 42 ppm. Exposure to 459 ppm of vapor was reported to be the symptom of dimmed vision which was the lowest concentration indicating optic nerve disorder. In the 1025.0 ppm of vapor, optic nerve disorders and central nerve disorders occurred. Conclusions Respiratory methanol exposure had initiated clinical symptoms as optic nerve toxicity from 459.0 ppm at the vapor phase. In the 1025.0 ppm of vapor, representative symptoms were identified such as optic nerve, and central nerve disorders.