Researchers Call For Ban of Common Chemical, Citing Link to Parkinson’s Disease

According to a new review published in the Journal of Parkinson’s Disease, a chemical commonly used for over a century may contribute to the growing incidence of Parkinson's disease, the world's fastest-growing brain condition.

The international team of researchers who authored the review, including University of Rochester Medical Center (URMC) neurologists Ray Dorsey, MD, Ruth Schneider, MD, and Karl Kieburtz, MD proposes that Trichloroethylene (TCE) could be an invisible cause of Parkinson's disease. The researchers have documented the extensive use of the chemical and the evidence linking it to Parkinson's disease.

“Through a literature review and seven illustrative cases, we postulate that this ubiquitous chemical is contributing to the global rise of Parkinson’s disease and that TCE is one of its invisible and highly preventable causes,” the researchers wrote.

The researchers called for a ban on the chemical in the United States, noting that TCE contamination has been found at 15 toxic Superfund sites in Silicon Valley and the Marine Corps base Camp Lejeune.

 According to an article in Parkinson’s News Today, TCE is banned in the European Union except for authorized industrial uses and it’s been banned by Minnesota and New York in the U.S., but not by the federal government.

Trichloroethylene (TCE), a simple, six-atom molecule that has been used for decaffeinating coffee, degreasing metal, and dry-cleaning clothes, is reportedly present in up to one-third of the groundwater in the United States. It has been linked to cancer, miscarriages, and congenital heart disease, and according to the review, is now associated with a 500 percent higher risk of Parkinson's disease.

The first case study to hint at a connection between TCE and Parkinson's disease was published in 1969. Since then, the review notes, research in rodents has revealed that TCE can easily enter the brain and body tissues, causing damage to mitochondria at high doses. Animal studies have also demonstrated the selective loss of dopamine-producing nerve cells, which is a significant feature of Parkinson's disease in humans.

According to a news article published by The University of Rochester Medical Center, TCE can infiltrate soil and groundwater, forming subterranean streams, or plumes, which can spread over extended distances and migrate over time. For example, an aerospace company on Long Island, New York, has a plume that is over four miles in length and two miles in width, contaminating the drinking water of thousands. Plumes can also be found in places like Newport Beach, California, and Shanghai, China.

According to the researchers, people who have had direct exposure to TCE are at a greater risk of developing Parkinson's disease. Nevertheless, the authors caution that "millions of people are unknowingly exposed to the chemical through contaminated groundwater, outdoor air, and indoor air pollution." They called for more studies into TCE’s potential health risks, for the cleanup of contaminated sites, and for more information to be made available about the dangers of contamination.