Presentation on Perchloroethylene and its Regulation: Colorado School of Public Health Department of Environmental and Occupational Health
Presented by: Elizabeth Bemis, Holly Kingsbury, Emily Steen,
Daniel Vigil, Petra Wolford
What is Perc?
PCE: PERC, Perchloroethylene
“A volatile organic
In 1985, worldwide production was
about 1 million metric tons
Widely used for dry
cleaning and as a metal
degreaser, in typewriter
correction fluid, and shoe
Small amounts are also
retained by recently dry
Where Else Can it be
•It is used as a
“building block” for
contain perc as well.
But, What is It?
•A synthetic chemical that at
room temperature is a
•An organic solvent that easily
dissolves organic material like oil
•It easily evaporates (volatile)
and has a sharp and sweet
odor, detectable in the air at a
level of 1 ppm.
How does a worker get
• Most likely exposure from the air we breathe
• Levels are usually several thousand times lower than what is found in dry
cleaning facilities, industrial operations, and waste sites.
• Exposure can also occur from contaminated groundwater, soil, food, and certain
• Water repellants, spot removers, adhesives, and wood cleaners.
• Perc may stay in the air for several months and eventually settle into the soil and
water because of precipitation
• For an average individual not living near businesses or waste sites that use or
contain PCE, exposure is well below the maximum exposure limits provided by the
EPA for workers.
• Individuals that work with PCE are at a greater risk for adverse health effects.
• According to NIOSH more than 650,000 U.S. workers may be exposed.
• We already know PCE can contaminate the air through evaporation from liquid solvent,
contaminated water, or contaminated soil
• Dry cleaners are a significant site of occupational exposure via inhalation:
• Risks from excessive inhalation as well
as spilling PCE solvent on exposed skin
• Loading dirty clothes into the machine
(displacement of pre-contaminated air)
• Removing clothes before the drying
cycle is finished
• Transferring solvent-laden clothes
into the dryer
• Cleaning and maintaining machines
• Possible: Pressing freshly dry-cleaned
Safe Exposure Limits
Organization 8-hour time weighted
OSHA (mandatory) PEL: 100 PPM Ceiling: 200 ppm for 5 min
in a 3 hour period
ACGIH (voluntary) TLV: 25 ppm STEL: 100 ppm
NIOSH Minimize workplace
85% of the more than 35,000 dry
cleaners in the United States use
PCE as a solvent in the dry cleaning
Health Risks with Exposure
Harm From Exposure: Cancer
EPA 2013: “likely to be carcinogenic to humans”
Human Epi Studies
•Increased risk of
Lymphoma and Multiple
•Leukemia and liver
cancer were caused in
•Kidney, brain and
testicular cancer also
Harm From Exposure: Neuro
EPA 2013: “Neurotoxicity was supported by considerable
evidence...and at lower concentrations”
Human Epi Studies
•Deficits in Visual Acuity
and Memory, Cognitive
Function, and Reaction
•Levels as low as 0.7ppm
•Same effects seen
•Changes in the
cortex & hippocampus
•Brain DNA, RNA,
protein and lipid
Harm From Exposure:
What about me?
• Occupational exposure
is in the range of
• Apartments sharing a
building with dry-
• Dry-cleaned clothes in
a vehicle ranged from
<0.1 to >3ppm
• Outdoor air near an
• PCE is highly
How Can PCE Be
Underground Plumes in
• There are at least 86
(from PERC) in
• 350 Dry Cleaners are
currently using PERC
in Colorado alone. It is
still legal to use.
The first step is to find Potentially
Responsible Parties (PRPs) and
discover each PRP’s allocated portion
Plumes are massive, cover miles and
involve numerous contributing
Remediation is extremely expensive
and involves years of litigation.
What Policies Are In Place?
National and State regulations have
helped in reducing harmful levels of
PERC in the air.
Because of epidemiological studies
we now know the harmful effects of
PERC and can better protect workers
and the public through remediation
activities and air and water quality
Requirement of “no new PERC dry
cleaning facilities” offers a promising
end to the PERC dry cleaning story.
• Agency for Toxic Substances and Disease Registry. (1997). "Toxicological Profile For Tetrachloroethylene". Atlanta, GA, p. 174. Retrieved
2012-09-16. citing C&EN, 1994, Facts and Figures for the Chemical Industry, Chemical and Engineering News, July 4, 1994.
• Agency for Toxic Substances and Disease Registry (1997). Public health statement: tetrachloroethylene. CAS#: 127-17-4. Available at:
http://www.atsdr.cdc.gov/ToxProfiles/tp18-c1-b.pdf. Accessed April 3, 2014.
• Environmental Protection Agency (2011). Removal of “Perc’ Pollution Begins at Former Cleaners
• Environmental Protection Agency. (2012). Toxicological Review of Tetrachloroethylene (CAS No. 127-18-4).
• Ferroni C, et.al. (1992). Neurobehavioral and neuroendocrine effects of occupational exposure to perchloroethylene, Neurotoxicology,
• Gold, Laura S. et.al. (2011). The Relationship between Multiple Myeloma and Occupational Exposure to Six Chlorinated Solvents;
Occupational and Environmental Medicine, 68(6): 391-399.
• Henshaw, S. (2013). Enviroforensics.com When Contaminated Groundwater Plumes Run Together, How is the Cost of Cleanup Divided?
Available at: http://www.enviroforensics.com/commingled-plumes-who-is-responsible-for-the-cleanup/
• National Center for Environmental Assessment, US Environmental Protection Agency. (2014). Human Health Effects of
Tetrachloroethylene: Key Findings and Scientific Issues. Available at: http://ehp.niehs.nih.gov/1307359/#tab2.
• NIOSH. (1994b). NIOSH manual of analytical methods. Third edition. Second supplement. Cincinnati, OH: NIOSH, U.S. Department of
Health and Human Services, National Institute for Occupational Safety and Health, NIOSH method no. 1003.
• Occupational Safety and Health Administration (2005). Reducing worker exposure to perchloroethylene (perc) in dry cleaning. Available at:
https://www.osha.gov/dsg/guidance/perc.html. Accessed April 3, 2014.
• Rossberg, M., et al. (2006). “Chlorinated Hydrocarbons” in Ullmann’s Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim.
• Seidler, A., et. al. (2007). Solvent exposure and malignant lymphoma: a population-based case-control study in Germany; Journal of
Occupational Medicine and Toxicology, 2:2.
• Stevens, Y., and Eisenmann, C. (1997). Toxicological Profile for Tetrachloroethylene. Retrieved from
• Tetracholorethylene (2006) Concise International Chemical Assessment Document 68. Available at: