A 68-year-old man presented to our emergency department with loss of consciousness after experiencing an irritant odor while molding fiber-reinforced plastic (FRP) without the use of appropriate respiratory protective equipment in a poorly ventilated environment. The patient was asymptomatic upon arrival at our hospital;however, based on his symptoms and a safety data sheet provided by his work manager, he was diagnosed with acute styrene poisoning. The patient was admitted to the intensive care unit and closely monitored. He was discharged on the third day of hospitalization without complications. Styrene may be generated during FRP molding. Styrene exposure can cause mucous membrane irritation and central nervous system dysfunction. Acute styrene poisoning should be considered in individuals who develop consciousness or respiratory issues during FRP production.
