Parkinson’s Disease Spikes Linked to Carpet Cleaning Chemical, say researchers

Researchers of a study on the link between neurological conditions and industrial and household solvent chemicals believe that the chemical trichloroethylene (TCE), a volatile organic compound (VOC), present in drinking water across the U.S. and still found in some commercial household products such as shoe polishes, aerosol cleaning products and carpet cleaners, among several other common household products* may be behind the recent spikes in Parkinson’s Disease**.  TCE can enter the 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.

“Our study confirms that common environmental contaminants may increase the risk of developing Parkinson’s, which has considerable public health implications.”

-Dr Samuel Goldman, The Parkinson’s Institute in Sunnyvale, California, and co-author of the study

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 its Final Risk Evaluation Report on TCE in late 2020, the EPA stated: “The final risk evaluation for TCE shows that there are unreasonable risks to workers, occupational non-users, consumers, and bystanders for 52 out of 54 conditions of use. Two conditions of use (distribution in commerce and consumer use in pepper spray) do not present an unreasonable risk. EPA also found no unreasonable risks to the environment…EPA is moving immediately to risk management for this chemical and will work to propose and finalize actions to protect workers, occupational non-users, consumers, and bystanders.”

In May 2020, Minnesota became the first state to ban TCE; New York followed suit in December 2020.

*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). While phased out of many cleaning products, in homes TCE may still be found in cleaning wipes, aerosol cleaning products, typewriter correction fluid, paint, and varnishes, paint removers, spray adhesives, and some carpet cleaners and spot removers. Commercial dry cleaners may also use 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).


**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’)



TCE can

***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.


Solutions for avoiding TCE

Minimize or avoid use of commercial household products containing this VOC. When this is not possible, wear protective gloves and keep the windows open to circulate air during use and for at least two hours following use. OR…for tasks like removing stains from carpets…DIY it with items from your cupboards:

diy carpet cleaning ingredients



1 Gallon of Hot Water (using filtered cold water is fine if you have a carpet extractor with a built-in heater)

1 ½ Tablespoons of Distilled White Vinegar

¼ Cup of 3% Hydrogen Peroxide

1 Tablespoon of Dawn (or any other dish soap)

5-6 drops of Lemon Essential Oil (optional, only for the fragrance)

Go here for the recipe.

Solutions for avoiding TCE in your water

TCE contaminates the tap water of 19 million people in 41 states. It is also likely an issue in many private wells, potentially affecting an additional 1.5 million people (source). Using activated carbon filtration devices (like Brita filters) or filtration systems with reverse osmosis can help reduce TCE in drinking water, but bathing in contaminated water, as well as inhaling vapors from toxic groundwater and soil, can be far more difficult to avoid (source).


Journal reference: Goldman, S.M., et al. Solvent exposures and parkinson disease risk in twins, Annals of Neurology Volume 71, Issue 6 p. 776-784.

Summary: Parkinson’s disease risk greater in those exposed to common chemical, trichloroethylene, study shows