top of page

Dry Cleaning

The most common method to “dry clean" clothing is a process that uses a toxic chemical solvent to remove stains. The chemical most commonly used for this purpose is the volatile organic compound perchloroethylene or PCE.  Perchloroethylene is also known as tetrachloroethylene, ethylene tetrachloride and carbon dichloride. During its manufacture and breakdown processes, PCE creates other hazardous substances, including dioxin, vinyl chloride, carbon tetrachloride and phosgene.


Although this chemical is regulated as a hazardous substance, almost 90% of dry cleaners in the U.S. still use PERC-based dry cleaning fluids. PCE is the most common groundwater and soil contaminant because it is highly persistent in the environment. It’s vapors also affect indoor air quality in spaces that are adjacent to a dry cleaner.


PCE exposure is associated with nervous system damage, liver and kidney damage, several types of cancer and reproductive impacts. Primary exposure pathways are inhalation and skin absorption.  That distinctive “sweet” smell in the air inside a dry cleaning establishment is volatilized PCE.

Fast Facts

  • Most dry cleaning establishments used the solvent perchloroethylene ("perc") to clean clothes.

  • Perc has been linked to nervous system damage, liver and kidney damage, several types of cancer and reproductive impacts.

  • Perc is the most common groundwater and soil contaminant at Superfund sites because it is highly persistent in the environment.

Studies show that nursing mothers who are occupationally exposed or who live in apartments above or adjacent to dry cleaning establishments often have enough PCE in their breast milk to put their infants at risk. Women who are pregnant should be aware that perchloroethylene also passes easily from the mother to the fetus.


There have been many efforts worldwide to develop alternative methods for dry cleaning, the best being wet cleaning and liquid carbon dioxide. 


Wet cleaning uses water and very mild detergents in computerized washers and dryers in additional to traditional pressing, steaming and finishing processes. The EPA considers it one of the safest professional dry cleaning methods because there is "no hazardous chemical use, no hazardous waste generation, no air pollution, and reduced potential for water and soil contamination."


Carbon dioxide (CO2) cleaning uses liquid CO2 as the cleaning agent along with detergent. The liquid CO2 is formed by placing the non-flammable and non-toxic gas under high pressure. It is then injected into specialized machines in both gas and liquid form and then pumped back out (captured) for reuse. The process is the most environmentally friendly because CO2 is naturally occurring and inexpensive and it uses less energy than traditional dry cleaning.  The downside is the initial investment in equipment, which is considerable.   (Liquid CO2 is non-toxic and is the same substance used to carbonate seltzer water and sodas.) 

Things you can do:

•  Clean your own clothes. Many items marked "Dry Clean Only," like sweaters and knits, can be easily cleaned by hand washing with cool water and a mild detergent. Reshape items on a flat surface before air drying.


•  Purchase machine-washable clothing.


• Find wet cleaning dry cleaners here:

Dry Cleaning Resorces
Dry Cleaning Resources

Related Websites
  • How Green Is My Town?- This online program, which addresses the three inextricably linked issues of sustainability, climate change and environmental health, provides a blueprint for 50 discreet issues, and contains the resources, templates, science and other essential tools to help every town achieve its environmental priorities.

Related Podcasts from Green Street
The Problem with Perc with Dr. David Carpenter
David Carpenter pic 2.jpg
bottom of page