Trichloroethylene Exposure May Raise Parkinson's Risk
Researchers investigated disease cluster in coworkers exposed to chemical for years
THURSDAY, Jan. 10 (HealthDay News) -- Chronic exposure to trichloroethylene appears to be a risk factor for Parkinson's disease, based on a study of a cluster of workers exposed to the chemical, and accompanying animal studies. The research was published online Dec. 21 in the Annals of Neurology.
Don M. Gash, Ph.D., of the University of Kentucky in Lexington, and colleagues evaluated the cases of three co-workers who developed diagnosed Parkinson's disease after years of dermal and inhalation exposure to trichloroethylene in the workplace. They also examined another 27 workers who responded to a questionnaire. In addition, researchers exposed male rats to the chemical by oral gavage.
Although 14 symptomatic employees didn't have Parkinson's, all showed some evidence of symptoms on a Parkinson's rating scale, and the group had slowed fine motor hand movements. The 13 asymptomatic workers also had slowed fine motor hand movements. In the animal studies, exposure resulted in Complex 1 mitochondrial impairment in the midbrain with loss of dopamine neurons.
"A large portion of the population has been exposed to trichloroethylene through its widespread use as a degreasing agent, inhaling it as an anesthetic, using products containing it, or drinking water contaminated with the organic compound from the numerous sites where it has been used or disposed. Trichloroethylene has been identified as an environmental contaminant in at least 852 of the 1,430 Superfund priority sites listed by the Environmental Protection Agency," the authors write. "It is widely found in drinking water, surface water and soils."