Trichloroethylene (TCE) has been widely used as a typewriter correction fluid, paint remover, adhesive, spot removers and, particularly, as a degreasing agent in metal-fabricating operation. However, few studies have reported on the effects of TCE intoxication, in spite of numerous occupational accidents arising from TCE intoxication, even until quite recently used in small companies. TCE affects mainly the central nervous system (CNS) and is carcinogenic, even when carefully used and managed.

A 48-year-old male worker visited our hospital complaining of decreased motivation and general weakness. In history taking, the patient had suffered insomnia, memory disturbance, stuttering, loss of interest and sexual desire, depressive mood for 4 years, dysesthesia with tingling sensation and pain in both extremities, and a nauseas feeling similar to a hangover which had been aggravated for 4 months before admission. The patient had been engaged in metal degreasing with TCE for 8 years. Electromyography indicated disturbance of autonomic function, but there was neither peripheral neuropathy nor cervical radiculopathy. Organic abnormalities including cerebellar atrophy and CNS infection were ruled out, while there was no indication of malignancy in magnetic resonance imaging (MRI) and metabolic disorders and electrolyte imbalances in laboratory test. The authors performed biological monitoring for the possible exposed chemicals. Urinary 2,5-hexanedione, a metabolite of n-hexane, was undetected but 3,331.1 mg/g creatinine of urinary trichloro-compounds, a metabolite of TCE, was detected. The patient was diagnosed as TCE intoxication due to a level of urinary trichloro-compounds in excess of the normal range (300 mg/g creatinine), in addition to an occupational history and clinical symptoms. TCE exposure was stopped in admission and the neuropsychiatric symptoms of the patient were improved as the urinary trichloro-compounds were decreased from 3,331.1 mg/g creatinine to 64.6 mg/g creatinine in 5 days.

Low-dose, chronic TCE intoxication shows neuropsychiatric symptoms, which are often misrecognized merely as a psychiatric disorder; its appropriate diagnosis, early treatment and exposure assessment are therefore difficult. The neuropsychiatric symptoms in workers who have been exposed to TCE should be monitored, detailed job history should be taken and biological monitoring should be conducted to gain early insight of chronic TCE exposure.