Are you concerned about the danger of perchloroethylene from dry cleaning to your health? This page answers many of the common questions about hazards from having clothes dry cleaned or working at a dry cleaners. The commercial drycleaning industry in the United States consists of approximately 36,000 shops. Most of these shops are small businesses with fewer than 10 employees. Approximately 85% of drycleaning shops in the U.S. use perchloroethylene as their primary solvent.
Researchers have conducted numerous studies of the commercial drycleaning industry. Some of these studies have evaluated a variety of health and safety hazards; however the greatest emphasis has been placed on worker exposure to perchloroethylene. Research in this industry has involved exposure assessment, engineering control evaluations, and epidemiologic studies. Information concerning these studies is outlined below.
This page is aimed at the general public, but you may also find it useful. We have another page that is written more for your needs at: Dry Cleaning wastes, by-products, regulatory compliance and guidance.
It is important for you to know the hazards associated with the use of liquid perchloroethylene (perc), and the kinds and sources of perc wastes that are produced by the dry cleaning process. Although perc is the most common cleaning solvent used in the dry cleaning industry, it is also suspected of causing cancer and has been found to be moderately toxic to people. It is classified as a pollutant in both air and water regulations. Its disposal is regulated as a hazardous waste.
The two largest potential sources of air emissions from the dry cleaning industry are the release of perc vapors into the atmosphere during transfer of clothes from the washer to the dryer and the venting of the dryer exhaust airstream. The concentrations of perc in the outside air is of concern to neighbors of dry cleaners! To eliminate these sources of air pollution, EPA regulations are phasing out the use of transfer machines and phasing in requirements on the installation of control devices for dryer exhaust airstreams.
Dry cleaning facilities typically generate wastes in the form of cooked powder residues, still bottom residues, spent cartridges, and button/lint trap wastes. These wastes are perc-based and have an EPA Hazardous Waste Number of F002. Dry cleaners may also occasionally dispose of unused perc and these wastes have a Hazardous Waste Number of U210. The EPA Hazardous Waste Number is needed when filling out the Notification of Hazardous Waste Activity form (Figure II-1, page II-24) when obtaining an EPA Identification Number for generating hazardous waste. It is also needed when filling out the Uniform Hazardous Waste Manifest (Figure II-6, page II-41). This Manifest must accompany each hazardous waste shipment to ensure the hazardous waste arrives at its final destination. Of course, most of the perc wastes are recycled instead of being disposed. In this case, they are not subject to the hazardous waste regulations.
The only source of process wastewater that would be of general concern to a dry cleaner is separater water, since it contains perc. Separator water can be disposed of as a hazardous waste or treated in a mister or an evaporator. Disposal of untreated separator water into on-site disposal systems such as dry wells, cesspools, and septic tanks is prohibited. Disposal into a municipal sewer system is subject to state and local Publicly Owned Treatment Works (POTW) requirements.
Despite its name, drycleaning is not totally dry. It involves the use of liquid chemicals called solvents that remove most stains from a variety of fabrics. Most drycleaners use perc as their primary solvent. Because the clothes are cleaned in a liquid solution that is mostly perc or some other solvent, with very little water if any, the term "drycleaning" is used to describe the process. There are some differences in the way drycleaners process clothes, but here is how it typically works:
Perchloroethylene, or perc, is the dominant chemical solvent used in drycleaning. It is is a clear, colorless liquid that has a sharp, sweet odor and evaporates quickly. It is an effective cleaning solvent and is used by most professional drycleaners because it removes stains and dirt from all common types of fabrics. Perc usually does not cause clothes to shrink, nor dyes to bleed. Perc is not flammable, unlike solvents commonly used to clean clothes in the 1930's and 40's. Since perc can be reused, it is a cost-effective and efficient solvent for cleaning clothes. Perc is also a toxic chemical with both human health and environmental concerns.
The extent of any health effects from perc exposure depends on the amount of perc and how long the exposure lasts. People exposed to high levels of perc, even for brief periods, may experience serious symptoms. Those include dizziness, fatigue, headaches, confusion, nausea, and skin, lung, eye and mucous membrane irritation. Repeated exposure to high levels can also irritate the skin, eyes, nose and mouth, and can cause liver damage and respiratory failure. Perc might cause effects at lower levels as well.
Studies in laboratory animals indicate that exposures to high levels of perc can produce effects on the developing fetus that include altered growth, birth defects, and death. While there have been studies of people who are exposed to high levels of perc, the studies are limited and inconclusive. Scientists have not yet determined whether perc exposures can cause such adverse effects in pregnant women as increased incidence of miscarriage or reproductive effects, affect women's fertility, or affect children born to parents exposed to high levels of perc.
The cancer-causing potential of perc has been extensively investigated. In laboratory studies, perc has been shown to cause cancer in rats and mice when they swallow or inhale it. There is also evidence, from several studies of workers in the laundry and drycleaning industry, suggesting a causal association between perc exposure and elevated risks of certain types of cancer. As with all health effects, the potential for an increased risk of cancer depends on several factors including how much perc exposure there is, how often the exposure occurs, and how long it lasts. Also important is the way the exposure occurs, as well as the individual's overall state of health, age, lifestyle, and family traits.
In 1995, the International Agency for Research on Cancer (IARC), convened a panel of internationally regarded experts which concluded that perc is "probably carcinogenic to humans," based on limited evidence of carcinogenicity in humans and sufficient evidence in animals.
To further understand risks associated with the use of perc, the Agency will be conducting a comprehensive, in-depth health effects assessment of perc through the Agency's Integrated Risk Information System (IRIS) process. IRIS is EPA's electronic on-line database of summary health risk assessment and regulatory information on specific chemicals, and was developed to provide consistent risk information for EPA decisions. The comprehensive health effects assessment will be peer reviewed, and the data and conclusions will be available in 1999 or 2000.
We all may be exposed to perc because it is found in the air and drinking water nationwide. Fortunately, the amounts are usually small enough that they are not hazardous to the average person's health. If you work in or live next to a drycleaning facility, you might be exposed to higher levels and may have cause for concern, especially if they are using older equipment that doe snot have good emission control and capture devices.
As a consumer of drycleaning services, you may be exposed to levels of perc that are slightly higher than what is normally found in the outdoor air; however, these amounts are not expected to be hazardous to the average person's health. Therefore, it is very unlikely that people will get cancer from having their clothes drycleaned. As with all health effects, the potential for an increased risk of cancer depends on several factors including how much perc exposure there is, how often the exposure occurs, and how long it lasts. Also important is the way the exposure occurs, as well as the individual's overall state of health, age, lifestyle, and family traits.
Professional cleaners remove perc from drycleaned clothes as part of the overall cleaning process. You cannot tell by odor alone whether all the perc has been removed from your clothes. If you think all of the solvent was not removed, or if your newly drycleaned clothes smell like solvent, ask your cleaner to re-process your order or take them to another cleaner for re-cleaning.
Based on occupational studies, there is some concern for drycleaning workers because people who work in traditional drycleaning shops are expected to have the highest exposures to perc. This is because they spend a lot of time inside the shops where the perc air levels are usually higher than levels found outside the shops.
There are many factors that influence perc air levels in drycleaning shops and each shop is unique. Perc evaporates quickly and can enter the air of drycleaning shops in many ways:
"Co-located" is a term used to describe cleaners that clean clothes on premises and are located in buildings that also house other businesses and/or residences. People who live or work in the same building as a co-located drycleaner can have greater than average exposures to perc. This is because perc vapors can pass through floor, ceiling, and wall materials of the drycleaning shop and into adjacent building space. Perc can also travel outside and re-enter nearby building spaces through holes, vents, and other means. A drycleaner could contaminate the air in neighboring apartments or offices if the cleaner has old equipment, does not properly maintain equipment, or does not follow proper safety procedures.
High perc levels in residences would be of special concern for irritation and other health effects, including a potential for cancer for occupants who are at home a lot and might be exposed to perc for extended periods of time, such as the elderly, young children, or pregnant women. Scientists do not know if perc exposures cause developmental changes in children.
Perc can get into the air, water and ground during the cleaning, purification, and waste disposal phases of drycleaning. Through recent improvements in equipment and more careful operating practices, perc consumption and losses to the environment are being reduced.
Most of the perc used by the drycleaning industry escapes into the outdoor air through open windows, vents, and air-conditioning systems. In older drycleaning systems, perc may still be vented directly to the outdoors as part of the drycleaning process. Fortunately, many drycleaners now use new machines that control or eliminate the amount of perc that escapes during the cleaning process.
Once outdoors, perc can remain in the atmosphere for several weeks, and although small amounts are always in the air, perc itself does not deplete the ozone layer of the atmosphere. After a few weeks, perc breaks down into other chemicals. Some of which are toxic, and some of which are suspected to deplete the ozone layer.
Perc is known to be toxic to plants. It can enter the ground in liquid form through spills, leaky pipes, leaky tanks, machine leaks, and from improperly handled waste. Significant amounts of perc have been found in the waste resulting from drycleaning, which is considered a hazardous waste by the EPA. Most of the solid waste materials, which are filters used during the drycleaning process as well as residual solvent and soils, are picked up by hazardous waste management companies for recycling and/or incineration.
At the end of the cleaning process, the cleaning fluid is separated from waste water by distillation. In the past, the waste water was often poured down floor drains. In newer equipment, the waste water is collected and evaporated, or removed by hazardous waste handlers and disposed of through EPA-approved methods.
Perc can seep through the ground and contaminate surface water, groundwater, and potentially drinking water. A small amount of perc can contaminate a large amount of water and people can be exposed by drinking or using the water. EPA has a limit on the amount of perc that is allowed to be in drinking water. Well water can be tested to be sure it is below the EPA standard.
Small amounts of perc in the water have been shown to be toxic to aquatic animals who can store the chemical in their fatty tissues.
Driven by concerns about perc and other drycleaning solvents, recent advances in both technology and garment care have resulted in a sophisticated machine-based process called "wetcleaning" which uses water as the solvent. Wetcleaning is done in specially-designed machines that have to be operated by garment care professionals. While professional cleaners have always employed some form of water-based cleaning methods, often by hand, these historic methods bear little resemblance to the new machine-based wetcleaning process.
Wetcleaning is not the same thing as home laundry and can only be done successfully by trained professional cleaners using the specialized machines and specially-formulated detergents and additives to gently wash and dry clothes. These machines are usually computerized, and like drycleaning machines, can be programmed to control many variables and allow cleaners to customize cleaning for different garments. Wetcleaned garments can require more work to press and specialized labor-saving equipment has been developed to press and finish wet- (or dry-) cleaned garments.
Wetcleaning is appealing from an environmental point of view because the cleaning process is done in a solution of water with a few percent of additives. As with any new technology, there are unanswered questions about the potential environmental impact of wetcleaning, in particular regarding water and energy use. Wetcleaning detergents and additives usually end up going down the drain, and the potential environmental effects of these new products are largely unknown. Certain chemicals traditionally used in detergents may pose concern for aquatic toxicity if they are also found in wetcleaning products.
Properly trained professional cleaners are now able to successfully wetclean most garments that are typically drycleaned. Silks, wool sweaters, linens, suedes and leathers can usually be wetcleaned, sometimes with superior results. Some cleaners offer wetcleaning to their chemically-sensitive customers. An increasing number of commercial cleaners are incorporating wetcleaning into their businesses. This trend is demonstrated by both the dramatically increasing number of machines that wetcleaning machine manufacturers report they have sold in the past few years, and the growth of the number of new wetcleaning products on the market.
For more information about wetcleaning and to get a partial list of cleaners nationwide that offer wetcleaning services, call the Pollution Prevention Information Clearinghouse (PPIC) at (202) 260-1023 and ask for EPA publication called Wetcleaning (EPA 744-K-96-002). Also, visit the most current list of self-identified wetcleaners.
Also available from PPIC is a curriculum for teaching drycleaners how to wetclean: Training Curriculum for Alternative Clothes Cleaning (EPA 744-R-97-004a). The manual also contains useful information on fabrics and fibers. Also, read current news and information on wetcleaning.
There are several new technologies on the horizon but only two are commercially available at this time: wetcleaning and a synthetic petroleum solvent process. The new petroleum solvent process has a reduced potential for fire hazards and is currently being used by some drycleaners. Even with the new process changes, some local fire codes still restrict or prohibit the use of these solvents because they are considered a fire hazard.
EPA hopes that in the near future, professional cleaners will have a wide range of environmentally-preferable cleaning processes to choose from. There are a number of new processes at different stages of development, such as:
The most important thing you can do is to choose a high quality cleaner who acts responsibly toward the environment. Most professional drycleaners are experts in fabricare and are already familiar with these issues. They will be able to advise you on whether or not your garments can be successfully cleaned in new cleaning processes. Some specific things you can do include:
The approximately 30,000 drycleaners in the United States share the public's concerns about risk to the environment and human health from exposure to cleaning solvents. Many professional cleaners have taken significant steps to reduce releases. A chemical industry survey reports that in the past ten years, drycleaners have reduced their use of perc by more than 60%. Most of this was accomplished through the replacement of old perc equipment with machines designed to reduce perc vapors going into the air, and better waste management.
Increasing numbers of drycleaners use new work practices which can significantly reduce perc exposures even in older equipment. Regular cleaning, inspection, and maintenance of equipment (e.g., ensuring repairing leaking gaskets and cleaning clogged dampers) help reduce perc emissions. In addition, some drycleaners install vapor barriers and build room enclosures which help keep perc from entering neighboring spaces, and provide safety training for workers to reduce worker exposures to perc.
An increasing number of commercial cleaners are incorporating new "greener" cleaning methods, such as wetcleaning, into their facilities. Some cleaners are involved in testing some of the emerging technologies still in development.