Smarter Living: Chemical Index
What is it and how can I recognize it?
A liquid. Methylene chloride is also known as dichloromethane, or DCM. It is a colorless, nonflammable liquid with a mild to moderate sweet aroma. It is a volatile organic compound (VOC) meaning that products containing methylene chloride can give off vapors for a long time.
Can it be found naturally?
Yes. Natural sources of methylene chloride include oceanic sources, macroalgae, wetlands, and volcanoes. However, the majority of methylene chloride in the environment is the result of industrial emissions.
Where is it found?
Household products. Methylene chloride is commonly found in the following products:
- paint strippers and removers
- spray shoe polish, water repellents
- wood floor and panel cleaners
- wood stains, varnishes and finishes
- heavy-duty surface cleaners and rust removers
- glues and adhesives, propellant in aerosols for products such as paints, automotive products, and insect sprays
Industrial processes. Methylene chloride is commonly used in:
- manufacturing of some drugs, pharmaceuticals, and film coatings
- metal cleaning and finishing solvent in electronics manufacturing
- decaffeination of coffee and tea as well as to prepare extracts of hops and other flavorings
How does it enter my body, and what are the health effects?
Breathing. The most common way that methylene chloride enters the body is by breathing it in (inhalation). This usually occurs in indoor environments where the gas has been released from methylene chloride-containing products. This can have a big impact on industrial workers' health who work indoors and are indirectly breathing in this chemical.
In addition, families or communities that live near hazardous waste sites are especially vulnerable. The wind can blow this chemical nearby and often methylene chloride attaches loosely to soil particles and is known to move from soil into the air.
In a 2014 report by the Environmental Protection Agency (EPA), it was recognized that there were "short-term and long-term risks for consumers and residential bystanders from the use of DCM-containing paint strippers."
Methylene chloride affects the nervous system (brain). It can cause headaches, dizziness, nausea, clumsiness, drowsiness, and other effects like those of being drunk. Effects on the nervous system can be long-lasting and possibly permanent if they occur frequently over months or years.
Methylene chloride can make angina and other heart symptoms worse in people with heart disease. People with lung conditions, smokers, and people who are overweight or pregnant also may be more sensitive to methylene chloride.
When inhaled or absorbed through the skin, methylene chloride can reach the developing fetus through the placenta, and it can enter breast milk.
Finally, prolonged skin contact can also result in methylene chloride causing skin irritation or chemical burns.
Does it cause cancer, and what kind?
Yes. The 2014 EPA report found that "DCM [methylene chloride] is likely to be carcinogenic in humans." In animal studies, breathing in methylene chloride causes tumors in the liver and lung.
How do I reduce my chance of getting sick?
Awareness and ventilation. Consumers and industrial users can reduce methylene chloride contamination by switching to less toxic products.
- Check the labels on items such as paint strippers and removers and avoid using household products that contain methylene chloride, also often listed as dichloromethane or DCM.
- Use products labeled "low-VOC" and follow all manufacturers' directions. (VOCs, or volatile organic compounds, are a category of chemicals that include methylene chloride.)
- Make sure you're working in a well-ventilated space if you are using a product that contains methylene chloride.
Consumers and industrial users should:
- Look for cleaners that can replace many industrial uses of methylene chloride, including neutral and alkaline water-based and soy-based paint strippers. Mechanical methods and benzyl alcohol are also both safer substitutes for methylene chloride-based paint strippers.
Capitol Hill. Consumers and industrial users can do only so much to protect themselves from harmful exposures to unsafe chemicals like methylene chloride. Congress must act to reform the Toxic Substances Control Act (TSCA) and require the chemical industry to substantially reduce people's exposure to chemicals of high concern like methylene chloride. Contact your Congressperson and get them to support reform of the Toxic Substances Control Act in order to keep the public safe. Support NRDC's efforts to get a good bill passed.
References and Additional Information
NRDC's factsheet on methylene chloride.
Agency for Toxic Substances and Disease Registry. Toxicological Profiles, Methylene Chloride, September 2000.
California Department of Public Health: Preventing Worker Deaths from Paint Strippers Containing Methylene Chloride
Gribble, Gordon W. (2009). Naturally Occurring Organohalogen Compounds. Springer. ISBN 321199324X. International Agency for Research on Cancer, Monograph on dichloromethane (PDF), vol 71. 1999.
The Institute for Research and Technical Assistance (IRTA), Glendale, CA. Methylene Chloride Consumer Product Paint Strippers: Low-VOC, Low Toxicity Alternatives. 2006.
National Institute for Occupational Safety and Health (NIOSH). 2005. Pocket guide to chemical hazards. DHHS (NIOSH) Publication No. 2005-149.
U.S. Department of Health and Human Services Household Products Database.
U.S. Environmental Protection Agency (US EPA). 1995. Integrated Risk Information System (IRIS). Dichloromethane.
last revised 10/14/2014