FAQ

How does dry cleaning work?

Despite its name, dry cleaning 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.

Dry cleaners usually treat spots by hand before placing garments in large machines. Liquid solvents, detergents, and sometimes a small amount of water, are added to the machines. The machines then agitate clothes in a manner similar to your own washing machine to remove dirt, oil, and stains. Once clean, the clothes are either dried in the same machine or transferred manually to a separate dryer, then pressed and shaped. Used solvent is distilled so it can be purified. Distillation separates the solvent from waste residues such as detergents, dye, dirt, oil, so the solvent can be reused. In addition to distillation, most machines also use filters to clean used solvent.

After the purification process, filters which contain the solvent in very small amounts, and certain solvent residues, such as perc, must be managed and disposed of as hazardous waste. Dry cleaners can send them to special facilities for recycling or incineration.

What is perc?

Perchloroethylene, or perc, is the dominant chemical solvent used in dry cleaning. 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.

What is perc? What are the human health concerns associated with perc?

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.

Can perc cause cancer?

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.

Am I exposed to perc and do I need to worry about it?

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.

Do I need to worry about wearing dry cleaned clothes?

As a consumer of dry cleaning 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 dry cleaned clothes smell like solvent, ask your cleaner to re-process your order or take them to another cleaner for re-cleaning.

Are there any new cleaning methods that may prove to be environmentally preferable?

Driven by concerns about perc and other dry cleaning solvents, recent advances in both technology and garment care have resulted in a sophisticated machine-based process called “wet cleaning” 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 wet cleaning products.

What garments can be successfully wet cleaned and where can I get this service?

Properly trained professional cleaners are now able to successfully wet clean most garments that are typically dry cleaned. Silks, wool sweaters, linens, suede and leather can usually be wet cleaned, sometimes with superior results. Some cleaners offer wet cleaning to their chemically-sensitive customers. An increasing number of commercial cleaners are incorporating wet cleaning into their businesses. This trend is demonstrated by both the dramatically increasing number of machines that wet cleaning machine manufacturers report they have sold in the past few years, and the growth of the number of new wet cleaning products on the market.

What are dry cleaners doing to reduce environmental and health risks from dry cleaning?

The approximately 30,000 dry cleaners 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.

What are dry cleaners doing to reduce environmental and health risks from dry cleaning?

The approximately 30,000 dry cleaners 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.

 

Source: epa.gov