Parkinson’s Disease Linked with Common Cleaning Chemical TCE: Case Studies

We reported two years ago about the link between Parkinson’s Disease and TCE (trichloroethylene), a known toxic and carcinogenic chemical that is banned in the European Union but still commonly used in the U.S.*  In an effort to further demonstrate the link between the disease, which is on the rise worldwide** and TCE, researchers have published a new report that includes case studies of individuals diagnosed with early onset Parkinson’s. Those cases include public figures such as former NBA star Brian Grant and actor Michael J. Fox.


TCE can



Researchers of a study on the link between neurological conditions and industrial and household solvent chemicals believe that the chemical TCE (trichloroethylene), a volatile organic compound (VOC), present in drinking water across the U.S. and still found in some commercial and consumer household products, may be behind the recent spikes in Parkinson’s Disease.  TCE has dozens of military, industrial, commercial, medical and consumer applications and is therefore widely used across the U.S. TCE can enter the human body through water, air, food and soil.  It easily evaporates into the atmosphere and enters groundwater. The negative health effects of TCE have been documented in the Journal of the American Medical Association since 1932.


Adverse health consequences linked with the toxic TCE chemical

TCE is a known carcinogen linked to renal cell carcinoma, cancers of the cervix, biliary passages, lymphatic system and male breast tissue. According to the National Cancer Institute, prolonged or repeated exposure of trichloroethylene causes kidney cancer.  Some evidence suggests that it may be associated with an increased risk of non-Hodgkin lymphoma, and possibly liver cancer, as well as immune system damage and harm to developing fetuses (source). However, its known relationship to Parkinson’s*** is often overlooked due to the fact that exposure to TCE can predate the disease’s onset by decades. (Those people living or working near National Priorities List Superfund sites–sites known to be contaminated with hazardous substances such as TCE–are at especially high risk of exposure.) While some people exposed may sicken quickly, others may unknowingly work or live on contaminated sites for most of their lives before developing symptoms of Parkinson’s. (source)

The US Department of Labor has issued a guidance on TCE: “The Board recommends […] exposures to… trichloroethylene (TCE) be presumed to cause, contribute, or aggravate Parkinsonism.



Where TCE may be hiding

The chemical TCE may be found in some shoe polishes, aerosol cleaning products and carpet cleaners, among other common household products like inks, dyes, computer electronics and soaps.  It may also be used in glues for cosmetics, wood finishes and stain removers. (Until the 1970’s it was used in the processing of decaffeinated coffee.) While phased out of many cleaning products, TCE may still be found in homes and home offices across the U.S in cleaning wipes, typewriter correction fluid, paint, and varnishes, paint removers, spray adhesives, and some spot removers. Commercial dry cleaners may also use TCE (trichloroethylene) as a spot remover (source), it may be present in pepper spray (source), and it is present in tap water in many states across the U.S.  (source).


Where TCE is banned in the U.S.

The chemical TCE (trichloroethylene) is still permitted for degreasing and spot dry cleaning in most of the United States and can be readily found in 48 states.  Only two states, New York and Minnesota, prohibited the use of TCE in 2020.  Despite continued warnings about its risks, the use of TCE is increasing worldwide. (source)


*While some countries heavily regulate TCE (its use is banned in the EU without special authorization) in the U.S., the Environmental Protection Agency (EPA) estimates that 250 million pounds of the chemical are still produced annually in the US, and that in 2017, more than 2 million pounds of the toxic chemical was released into the environment from industrial sites, contaminating air, soil and water.  Under EPA regulations, it’s considered “safe” for TCE to be present in drinking water at a maximum concentration of five parts per billion. Scientists with the Environmental Working Group (EWG) argue this limit does not fully protect against the risk of cancer and harm to the developing fetus. EWG’s health guideline is 0.4 ppb (source).

In late 2020 the EPA reported that common commercial uses of TCE are as a solvent in vapor degreasing, dry cleaning, spot cleaners, stain removers, and adhesives and sealants. Consumer uses include adhesives, degreasers, and cleaners (source).  TCE persists in the environment for decades. It is a volatile organic compound, which means it can enter indoor air as a gas, and through water in pipes, exposing people to it through inhalation when they are bathing, washing dishes and doing other water-related household activities (source).


**Parkinson’s disease is already the fastest-growing neurological disorder in the world; in the US, the number of people with Parkinson’s has increased 35% the last 10 years. A 2008 peer-reviewed study in the Annals of Neurology, for example, found that TCE is “a risk factor for parkinsonism.” And a 2011 study echoed those results, finding “a six-fold increase in the risk of developing Parkinson’s in individuals exposed in the workplace to trichloroethylene (TCE).

(Source: Dr. Ray Dorsey, neurologist, University of Rochester Medical Center and author of ‘Ending Parkinson’s Disease’)


***A small epidemiological study found that occupational or hobby exposure to solvents containing TCE was associated with a 500% increased risk of developing Parkinson’s Disease. (source)

Journal reference: Ray, D.E., et al. Trichloroethylene: An Invisible Cause of Parkinson’s Disease? Journal: Journal of Parkinson’s Disease, vol. 13, no. 2, pp. 203-218, March, 2023.                    DOI: 10.3233/JPD-225047  Published study