regulations get tighter each decade as we learn more about the environmental
increased health risks associated
with dry-cleaning chemicals. Industry representatives continue to deny
any adverse health effects. Several years ago, this writer was delighted
to find a local proprietor who had switched her entire business to "wet-cleaning" and
could successfully clean any garment brought to her shop. Shortly after
purchasing a new "wet" machine for $40,000, her old chemical
machine ceased to function. The next day she was scheduled for an inspection
by the Environmental Protection Agency (EPA) to check for compliance
in proper handling, storage, and disposal of the dry-cleaning chemicals
(with hefty fines for violators). She decided then and there not to
replace the $80,000 chemical machine. She would no longer need gloves,
masks, monitoring devices, secure containers, or a special "vapor" room.
She was thrilled to be free of further EPA inspections and to provide
a healthier workplace for herself and her employees. The Cancer Awareness
Coalition, Inc., a grassroots organization with which I am affiliated,
decided to present this new environmentally friendly
business with its annual Earth Day Award.
The process of using petroleum-based solvents to clean clothes was discovered
in the mid-1800s by a French dye-works owner, Jean Baptiste Jolly. He noticed
how clean a tablecloth looked after an accidental spill of kerosene. He then
developed a service to clean other people's clothing using solvents
instead of water and referred to it as "dry-cleaning." Early
fires and explosions let to heavy regulations of dry-cleaners. Gasoline and
kerosene, the first solvents used, were later replaced with less flammable
Tetrachloroethylene or perchloroethylene, commonly known as "PERC," was
considered an ideal solvent because it is stable, non-flammable, gentle to
most fabrics, and an excellent cleaner. PERC was first used in the 1920s as
a metal cleaner in Germany. It was found to dissolve dirt from a wool suit
without harming the garment, and best of all, it did not explode.2 Dow Chemical
and Imperial Chemical Industries recognized a good thing when they saw it.
PERC happens to be a by-product of the manufacture of chlorofluorocarbons (CFCs),
which were used in Styrofoam, air-conditioning, and spray propellants until
they were banned in 1996 for eroding the earth's ozone layer.2
Tetrachloroethylene is used as a dry-cleaning solvent and in consumer products
such as paint and spot removers, water repellants, brake and wood cleaners,
glues, and suede protectors. It is also known as perchloroethylene, PCE,
perclene, and perchlor. In the dry-cleaning industry it is most commonly
referred to as PERC.3,4
At room temperature, PERC is a colorless liquid that readily evaporates into
air. Evaporation from industrial and dry-cleaning facilities contaminates air
and ground water, from which many communities get their drinking water. As
late as the mid-1980s, it was legal to dispose of excess PERC by pouring it
down the drain. Now, it must be handled as hazardous waste – at great
expense to shop owners. How many businesses still pour it down the drain is
unknown. PERC evaporates into air from dry-cleaned clothes or from applications
of spot removers. Poorly ventilated areas will have higher concentrations of
PERC enters the bloodstream via inhalation and can be stored in fat, liver,
and brain tissue. A New York State Fact Sheet on PERC indicates it can also
be absorbed via skin contact from contaminated soil, but the average consumer
is more likely to have skin contact with chemical residue in dry-cleaned
clothing than with contaminated soil.
According to a 1996 analysis by Consumers Union (publishers of Consumer
one of 6,700 people who wear freshly dry-cleaned garments at least once a week
could be expected to get cancer over their lifetime from inhaling PERC fumes
left in the fabric.2,3
PERC can have a negative effect on the central nervous system, kidney, liver,
and reproductive systems of humans and animals, depending on the length and
intensity of exposure. Observations on the effects of short-term (less than
14 days) exposure to PERC in animals have shown the following: damage to fetus,
reduced body weight of mother, behavior changes, and liver damage. Short-term
exposure in humans has caused dizziness, headache, sleepiness, lightheadedness,
poor balance, and eye, nose, and throat irritation. Visual impairment, reduced
test scores, attention deficit, reaction time, and eye-hand coordination problems
have also been observed. Acute high-level PERC exposures have been associated
with blindness and child death.3,4
Long-term exposure (greater than 14 days) in animals has resulted in kidney
tumors, leukemia, liver tumors, and changes in brain chemistry. Observed risks
in humans includes reduced visual perception; learning, memory, and attention
impairment; and liver and kidney damage (in dry-cleaning workers).3
There may be an increased risk of esophagus and bladder cancers and non-Hodgkin's
lymphoma from PERC exposure. Reproductive risks include spontaneous abortion,
menstrual and sperm disorders, and reduced fertility. Cancers of the cervix,
tongue, and lung showed a less clear association with PERC exposure. The New
York State Department of Health (NYSDOH) recommends the average air level in
residential buildings not exceed 100 micrograms of PERC per cubic meter of
air. (Questions about PERC can be directed to the NYSDOH by calling 800-458-1158
PERC can be passed into breast milk from a woman's environmental exposure
to the toxic chemical, though a greater risk is from occupational exposures.
When volatile chemicals are inhaled, they are readily absorbed and circulated
by the bloodstream. Lipophilic chemicals move from blood into fat tissue, where
they can be stored for long periods of time and easily transported into breast
milk. Tetrachloroethylene is one of many solvents that escapes odor detection
until levels exceed suitable indoor air quality guidelines.5,6
A 1991 study by the NYSDOH found elevated levels of PERC in dry-cleaning facilities
and other locations in the same building such as residential apartments and
offices. Apartments located above the dry-cleaning businesses had substantially
elevated concentrations of the chemical. Samples of breath, urine, blood,
and breast milk also showed presence of the volatile solvent. The study came
about because of health complaints from residents living above dry-cleaning
establishments. Studies also found high levels of PERC in butter and other
fatty foods in grocery and convenience stores located next to dry-cleaning
The EPA has been increasingly concerned about risks associated with PERC. In
July 2006, the agency again tightened air toxics requirements for all dry-cleaners
using perchloroethylene, requiring businesses to further reduce PERC emissions.
The new regulations require the elimination of transfer machines, which allow
greater amounts of PERC to escape when wet clothes are "transferred" to
a different machine for drying. Newer equipment allows cleaning and drying
in the same machine.8
Shop owners are required to do monthly monitoring using specialized sensors
to detect PERC leaks, repair all leaks, and maintain thorough records. Businesses
located in residential buildings must phase out PERC entirely, and all existing
PERC machines must be removed from residential buildings by December 21, 2020
and replaced with non-PERC equipment.8
The scientific community knew as early as the 1970s that PERC caused liver
cancer in mice; for that reason, the EPA classified it as a carcinogen in high
doses. EPA scientists earnestly began researching risks associated with PERC
exposure in the 1980s and made repeated attempts to better protect the environment
and human health from this toxic chemical.2
Investigative journalist and author Dan Fagin describes federal officials as
being "mired in the hopeless mission of placating different interest
groups." While the EPA and industry sparred over regulating PERC, the
International Agency for Research on Cancer meeting in Lyon, France concluded
that new studies of PERC risks should raise its designation from a possible
carcinogen to a probable carcinogen.2
In the normal course of negotiating protective legislation, our regulatory
agencies must consult with industry stakeholders before making any final declarations.
In this case, industry demanded that the EPA's final report eliminate
all figures relating to the health risks of PERC, claiming "Media attention
would needlessly alarm…employees and customers, and result in significant
economic harm to…family-owned-and-operated small businesses," according
to a letter signed by Dow Chemical and other business and franchise representatives.2
On the other side, the EPA was getting pressure from Greenpeace to reveal the
figures on health risks to the public. The final figures were constructed to
be somewhat vague; originally, however, the cancer risks were shown to be one
in ten for dry-cleaning workers and one in 10,000 for the public at-large.
While industry's influence was slowing EPA's efforts to protect
American workers and consumers, the German government enacted strict rules
requiring PERC fumes to be as low as one-tenth what the US government allowed,
thereby encouraging alternative PERC-free technology. Another problem with
traditional dry-cleaning is that leftover solvents and residues that are cooked
down or distilled into a muck must be handled as hazardous waste.1,2
California Bans PERC
The state of California has taken the lead role in passing the nation's
first statewide ban on toxic dry-cleaning chemicals and equipment. PERC will
be phased out beginning 2008. Dry-cleaners located in residential buildings
must remove PERC machines by July 2010, and by 2023, dry-cleaning machines
that use PERC will no longer be allowed in the state. Health advocates are
pushing for an earlier timetable to be applied to cleaners located near schools,
daycare centers, medical buildings, and retirement homes.9
Pressure is on, and the dry-cleaning industry is making strides toward safer
procedures. Approximately 85% of dry-cleaning establishments still use PERC.
However, a growing number of businesses around the country are introducing "Green
Earth®," "eco-friendly," and plain old "water" cleaning,
which can successfully clean silks, wools, and – with the right professional – even
leather. Look for my follow-up column on safer dry-cleaning options in the
next issue of the Townsend Letter.
Rose Marie Williams, MA
156 Sparkling Ridge Road
New Paltz, New York 12561
1. Dry cleaning. Available at: http://wikipedia.org.
Accessed March 14, 2007.
(June 2007 note: Try http://en.wikipedia.org/wiki/Dry_clean)
2. Fagin, D, Lavelle, M. Toxic Deception,
Monroe, Maine: Common Courage Press;
3. Fact Sheet – Tetrachloroethene (Perc) in Indoor and Outdoor Air. New
York State Dept. of Health. May 2003. Available at: http://www.health.state.ny.us/environmental/chemicals/tetrachloroethene/index.htm.
Accessed April 4, 2007.
4. Dry cleaning chemicals. Available at: http://www.niehs.nih.gov/search. Accessed
March 8, 2007.
(June 2007: Link not valid. Try http://www.niehs.nih.gov/external/faq/perc.htm)
5. Schreiber, J, Hudnell, HK, Geller, A, et al. Apartment residents' and
day care workers' exposure to tetrachloroethylene and deficits in visual
contrast sensitivity. Environmental Health Perspectives (Jrnl
Enviro Health Sci). July 2002; 110 (7): 656.
6. Schreiber, J. Parents worried about breast milk contamination. Children's
Environmental Health (NYS Office of Atty Gen,
Environ Protection Brd). Oct 2001;
7. New York State Dry Cleaner Survey. New York State Department of Health, Bureau
Toxic Substance Assessment. November 1993.
8. Fact Sheet – Final Amendments to Air Toxics Standards for Perchloroethylene
Dry Cleaners (US EPA). Available at: http://www.epa.gov/drycleaningrule/percfs20060717.html.
Accessed April 4, 2007.
9. Young S. California bans dry-cleaning chemical. Associated Press release.
Available at: http://www.sfgate.com/cgi-bin/article.cgi?file=/news/archive/2007/01/25/national/a154948S99.DTL.
Accessed April 4, 2007.