Introduction

The Toxics Use Reduction Institute is a Massachusetts government research entity that has used the unique usage data from the state pollution prevention program to create selected chemical fact sheets. The following is from the TURI Perchloroethylene Fact Sheet.

Most organic materials are able to dissolve, perchloroethylene (PCE) is the most widely used dry cleaning solvent in Massachusetts and nationally. Its other major uses are as a metal degreaser, a chemical intermediate and an ingredient in consumer products, such as automotive aerosol parts cleaners and degreasers. PCE is reported to be the chemical most widely found in groundwater contamination at Superfund sites. Testing at TURI’s laboratory over the years has revealed a number of suitable replacement cleaners and solvents for many of the uses of PCE throughout various industry sectors. This information can be found on the laboratory’s website or by contacting the lab directly at 978-934-3133.

Use Nationally and in Massachusetts

Uses of PCE nationally typically fall into one of the following categories:

• The major use of PCE is as the basic raw material in the manufacture of hydrofluorocarbon (HFC 134a), a popular alternative to chlorofluorocarbon (CFC) refrigerants. It also is used in the synthesis of several hydrochlorofluorocarbons (HCFC 123 and 124 and HFC 125). In 2004 over 66% of the 355 million pounds of PCE use in the US was for this application.
• Dry cleaning represents 12% of the total PCE usage nationally (43 million pounds, down from 86 million pounds in 1998). The decrease in usage can be attributed to the improved efficiency of dry cleaning machines in the industry as well as the emergence of alternative cleaning processes and chemicals. PCE currently comprises 70% of all commercial dry cleaning solvents.
• In 2004, aerosol products (for cleaning tires, brakes, engines, carburetors and wire, and as an anti-seizing agent) made up 12% of the total use of PCE.
• The use of PCE as an industrial metal cleaning and degreasing agent has declined 16%, from 34.4 million to 28.4 million pounds since 1998. In 2004, 8% of all PCE was used for this purpose.

Table 1 summarizes the historical use of PCE in Massachusetts. The data show the amounts of PCE reported to the Massachusetts Toxics Use Reduction Program for 1990 and 2004. Of the companies that reported their use of PCE in 1990, only one, Shield Packaging, was still using reportable amounts of PCE in 2004. The company is a packager of aerosol products. Some of the companies who reported using PCE in 1990 found alternative formulations or modified their operations so as to reduce their use of PCE to below the applicable reporting threshold of 10,000 pounds per year. Overall, Massachusetts has experienced a 73% reduction in the use of PCE since 1990.

Figure 1. Illustrates the percent changes in use of PCE in Massachusetts by industry sector. The printing and plastics sectors both completely reduced their usage of PCE below the reporting threshold.

The electronics sector increased its use of PCE by 57%. A portion of this increase was associated with Aerovox which has been increasing production in the Commonwealth since 2000. As of spring 2005, however, this sector will show a 100% decrease in PCE usage as Aerovox, working with the TURI Laboratory and the Massachusetts Office of Technical Assistance, was able to eliminate its use of PCE and TCE in its vapor degreasing operations. The company was able to identify viable drop-in alternative vapor degreasers, allowing Aerovox to completely eliminate their use of TCE and PCE.

While the dry cleaning/textiles processing sector shows an overall reduction of 76%, this is due to the difference in operational changes in the two reporting companies. Swan Finishing Company reduced its use of PCE below reporting thresholds within one year of reporting, though it continued to manufacture flame retardant and other finished textiles until 2003. On the other hand, Adams Laundry, an industrial dry cleaning facility, first exceeded the reporting threshold for PCE in 1991, and has maintained steady or increased production since that time.

The metal working sector showed an 86% decrease in PCE usage over the 1990 to 2004 time frame. Of the companies in this sector, Fountain Plating is the only one that was still using reportable amounts of PCE in 2004 for its metal parts masking metal parts process. Springfield Wire continues its operations, but was able to modify its processes to reduce its use of PCE below the 10,000 pound per year threshold by 1994. Presmet continued operations in Massachusetts until recently though it was able to eliminate its use of PCE by 1991.

Figure 2. Inputs and outputs of PCE

The chemical packaging sector reduced its use of PCE by 63% from 1990 to 2004. Callahan Company and Astro Chemical repackage PCE for bulk sales. Shield Packaging mixes and packages aerosol formulations containing PCE for other companies. Shield reported a 31 percent increase in use of PCE from 1990 to 2004. However this company relies on the requirements of its customers to dictate the formulations it manufactures and therefore is limited in its ability to reduce PCE use other than through education of its customers. Working with the TURA program, Aerovox was recently able to eliminate over 20,000 pounds of PCE use in the electronics sector.

Figure 2 illustrates the change from 1990 to 2004 in inputs and outputs of PCE in Massachusetts. Inputs include PCE that is manufactured or processed, as well as PCE that is “otherwise used”– ancillary uses that do not become incorporated into the final product. Outputs include PCE that is generated as byproduct (i.e., all non-product material created by a process line prior to release, on-site treatment, or transfer) and the amount of PCE that is shipped in or as product.

Both inputs and outputs of PCE were significantly reduced overall in the Commonwealth from 1990 to 2004. Specifically, from 1990 to 2004 the total input of PCE, including otherwise used, manufactured or processed PCE, was reduced by 85%, while the total output of PCE, the amount generated as byproduct, shipped in or as product, over the same time period was reduced by 89%. (It is likely that there will be a further decrease in PCE use for 2005 due to Aerovox discontinuing use of PCE for cleaning in 2005.)

Regulatory Context

The US Occupational Safety and Health Administration (OSHA), the US Environmental Protection Agency (EPA) and the US Food and Drug Administration (FDA) regulate PCE.

The OSHA permissible exposure limit (PEL) for PCE is 100 parts per million (ppm) for an 8 hour day (time weighted average) with a maximum exposure level (ceiling) of 200 ppm, except that an exposure of 300 ppm (peak) is allowed for 5 minutes in any 3 hour period.

The US EPA regulates PCE in a number of ways:

• Clean Air Act National Emission Standards for Hazardous Air Pollutants (NESHAP) for Organic Solvent Degreasing:

• This NESHAP sets two standards. The MACT-based equipment and work practice compliance standard requires a facility to use a designated type of pollution prevention technology along with proper operating procedures. Existing operations that use a performance-based standard can continue to do so if they can achieve the same level of control as the equipment and work practice compliance standard.
• Urban Air Toxics Strategy: PCE is identified as one of 33 HAPs that present the greatest threat to public health in urban areas and are therefore regulated.

• Air Toxics Standards for Perchloroethylene Dry Cleaners

• On July 13, 2006, the EPA strengthened the air toxics requirements for dry cleaners using PCE. The rule includes a phase-out of PCE used at dry cleaners located in residential buildings, along with requirements that will reduce PCE emissions at other dry cleaning facilities.
• Clean Water Act
• Effluent Guidelines: Listed as a Toxic Pollutant for several industry categories
• Water Quality Criteria: Based on fish/shellfish and water consumption = 0.69 ?g/L; based on fish/shellfish consumption only = 3.3 ?g/L

• Comprehensive Environmental Response, Compensation, and Liability Act Reportable Quantity (RQ) = 100 lb

• Emergency Planning and Community Right-To-Know Act Toxics Release Inventory: Listed substance subject to reporting requirements

• Resource Conservation and Recovery Act
• Listed Hazardous Waste: Waste codes in which listing is based wholly or partly on substance - U210, F001, F002, F024, F025, K019, K020, K073, K116, K150, K151
• Characteristic Toxic Hazardous Waste: TCLP Threshold = 0.7 mg/L
• Listed as a Hazardous Constituent of Waste
• Safe Drinking Water Act Maximum Contaminant Level (MCL) = 0.005 mg.

The US FDA regulates PCE. Its maximum permissible level in bottled water is 0.005 mg^[1].

Further Reading

• The Toxics Use Reduction Institute homepage
• Five Chemicals Study

Endnote

^ 1. National Toxicology Program 2005, Tetrachloroethylene (Perchloroethylene) CAS No. 127-18-4, United States Department of Health and Human Services. OSHA, Chemical Sampling Information, http://www.osha.gov/dts/chemicalsampling/data/CH_270620.html, updated Jan, 2006; EPA Fact Sheet - Final Amendments to Air Toxics Standards for Perchloroethylene Dry Cleaners [Dry Cleaning Emission Standards], [Online]. Available: http://www.epa.gov/air/ drycleaningrule/percfs20060717.html [June 12th, 2007]

Editor's Notes

• Other names for perchloroethylene include tetrachloroethylene, perc, tetrachloroethene, perclene, and perchlor.
• The Encyclopedia of Earth article "Public Health Statement for Tetrachloroethylene" supplements this entry.