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# Dry Cleaning Alternative Solvents: Health and Environmental Impa cts

In January, 2007, the California Air Resources Boar d (ARB) amended its regulations addressing perchloroethlylene (Perc) emissions from dry cleani ng operations. These amendments are effective as o f December 27, 2007, and include:

• January 1, 2008: No new sale or lease of Perc machines;

• July 1, 2010: All Perc machines at co-residential facilities must be removed;

• July 1, 2010: Perc machines 15 years and older may no longer be u sed;

• January 1, 2023 : Perc machines may no longer be used.

The ARB determined that the benefits from dry clean ing alternatives outweigh the negative health and environmental impacts from the use of Perc.

Questions have been raised about potential health i mpacts of alternatives to Perc. We offer this fact sheet

to describe the available alternative solvents and provide current information on their health and environmental impacts.

The alternative solvents listed are either already in use or are being considered for use in Californi a. This

information is not meant to be exhaustive as other solvents may also be available.

Approved Non-toxic and Non-smog-forming Dry Cleanin g Technologies

These systems qualify for grant money under Califor nia’s Non-Toxic Dry Cleaning Incentive Program, established by Assembly Bill (AB) 998.

Water-Based Cleaning

Water-based cleaning systems use water and detergen ts to clean garments. Currently, there are three types available: 1) professional wet cleaning syst ems; 2) cold water cleaning systems; and, 3) Green Jet 
dry-wet cleaning  systems.

• Health and Environmental Impacts

Most detergents used in wet cleaning are a complex mixture of water and chemicals. Because there are a wide variety of formulations, it can be diffi cult to determine the toxicity of specific products . In general, detergents are approved for disposal into sewer systems by local sanitation districts. The United States Environmental Protection Agency exami ned the human health and environmental hazards of the primary components of detergents and found no expected health risks to the general public.

Carbon Dioxide (CO 2 )

The CO 2 process, developed by commercial and retail dry cl eaners, is a high pressure system using liquid

CO 2 as the cleaning solvent. 

# Fact Sheet Fact Sheet

March 20082

• Health and Environmental Impacts

CO 2 is a non-flammable, non-toxic, naturally-occurring gas that becomes a liquid solvent when subjected to pressure. There is no expected health risk to the general public from these processes.
Questions have been raised because CO 2 is a greenhouse gas which contributes to global wa rming. Although the amount of emissions from dry cleaning processes have not been studied, the CO 2 used in the dry cleaning processes is a by-product from industrial operations and therefore does not contribute to the greenhouse gas inventory.

Financial Assistance

Financial assistance is available for water-based a nd CO 2 cleaning systems through the AB 998 Non-Toxic Dry Cleaning Incentive Program. This program provid es $10,000 grants to dry cleaners that choose to replace their Perc dry cleaning system with a non-t oxic and non-smog forming system. Currently, only

water-based and CO 2 cleaning systems qualify as approved technologies. A statewide demonstration program was also established to showcase these qual ifying technologies, and to provide an opportunity to educate business owners of the benefits, costs, and effectiveness of these alternatives. More inform ation

can be found at http://www.arb.ca.gov/toxics/dryclean/ab998.htm

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In addition to ARB’s Non-Toxic Dry Cleaning Incenti ve Program, some local air districts offer incentiv es for

water-base and CO 2 cleaning systems. A list of the local air distric ts’ contact information can be found on the following website: http://www.arb.ca.gov/capcoa/roster.htm

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Other Available Dry Cleaning Technologies

The following systems are currently being used or b eing considered for use in California as alternativ es to

Perc machines.

Hydrocarbon Solvents

Currently, the types of hydrocarbon solvent technol ogies available are: 1) DF-2000  Fluid; 2) PureDry  ; 3) EcoSolv  ; 4) Shell Sol 140 HT; and, 5) Stoddard solvent. T he machines predominately used for hydrocarbon solvents are closed-loop machines equip ped with primary controls. Detailed information on each of the hydrocarbons is available in the Air Re sources Board staff report available at http://www.arb.ca.gov/regact/2007/perc07/perc07.htm

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• Health and Environmental Impacts

There is limited health information on these hydroc arbon mixtures with the exception of the Stoddard solvent. None of the hydrocarbon solvents have und ergone formal evaluation by California for identification as toxic air contaminants (TAC). A two-year inhalation study of Stoddard solvent conducted by the National Toxicology Program (NTP) concluded that there was some evidence of carcinogenic activity in male rats. Additionally, Stoddard solvent can be irritating to the eyes, nos e, throat, and can also have effects on the nervous sy stem. A detrimental and secondary health effect of the alternative solvents is that all hydrocarbon solvents are considered volatile organic compounds (VOC). VOCs contribute to the formation of ozone which is linked to many ill-health effects including respiratory irritation, asthma, a nd premature death.

GreenEarth ®

(Volatile Methyl Siloxane)

Decamethylcyclopentasiloxane (D 5 ) or volatile methyl siloxane is an odorless, color less liquid that has many consumer and industrial applications. D 5 is the ingredient present in the GreenEarth  dry cleaning solvent

used in multi-solvent machines. The ARB does not c onsider D 5 to be a VOC.3

• Health and Environmental Impacts

California’s Office of Environmental Health Hazard Assessment (OEHHA) recently conducted an

evaluation of the available D 5 information and concluded that exposures of D 5 at the highest achievable vapor concentrations cause uterine tumor s in rats. OEHHA is also concerned about the potential non-carcinogenic effects associated with D 5 and its apparent persistence in the environment and animal and human tissues. However, available exposure information indicates that

the use of D 5 as an alternative dry cleaning solvent will not po se a risk to the public living near businesses using D 5

. D 5 has not undergone formal evaluation for identifica tion as a TAC.

Rynex

 (Rynex 3 or Propylene Glycol Ether)

Rynex  (Rynex 3) is an organic and biodegradable solvent with low volatility and a high flash point. It is considered a VOC. Rynex 3 can be used in most hydr ocarbon machines with some temperature and timing adjustments.

• Health and Environmental Impacts

Rynex 3 consists of a mixture of glycol ethers. Th is solvent brand has changed formulation since its inception. Based on a recent study by NTP on the g lycol ether ingredient of a previous formulation for Rynex  , propylene glycol t-butyl ether (PGtBE), OEHHA has expressed concerns over its toxicity and carcinogenic potential. Of particular concern, was the presence of tumors in mice. More detailed information on the toxicological studies f or the previous formulation of Rynex  can be found in the Technical Assessment Report. Rynex 3 repres ents the current formulation for Rynex  , which does not contain PGtBE but instead contains dipropy lene glycol tert-butyl ether (DPTB). Currently, there is limited toxicity data available for DPTB. It has not undergone formal evaluation for

identification as a TAC.

Limited Use Dry Cleaning Technologies

1-Bromopropane (n-propyl bromide)

1-Bromopropane (n-propyl bromide or n-PB or DrySolv ) is an emerging technology which is currently bein g used outside of California. It is considered a VOC . Although this solvent is being used in modified perchloroethlylene-dry-cleaning machines with secon dary control, industry representatives are concerne d that n-propyl bromide’s inherent properties may lea d to more leaks and emissions in such machines.

• Health and Environmental Impacts

According to the California Department of Health Se rvices, this solvent is a neurotoxicant and reproductive toxicant and is listed under Propositi on 65 as a reproductive toxicant. It causes steril ity in both male and female test animals, and harms dev eloping fetuses. It can damage nerves, causing weakness, pain, numbness, and paralysis. 1 -Bromopropane has a strong odor and is a more volatile compound than Perc, thus increasing i ts potential for nuisance problems and exposure to near-by residents. This compound has not underg one formal evaluation for identification as a

TAC.

Solvair

TM (dipropylene glycol normal butyl ether/ CO 2 )

Solvair is a recently available commercial dry clea ning technology. The Solvair equipment uses a clos ed loop process in which dipropylene glycol n-butyl et her (DPNB) is used as the base cleaning and liquid CO 2 is used to rinse out the solvent and dry the garmen ts.4

• Health and Environmental Impacts

DPNB is a type of propylene glycol ether. Currentl y, there is limited toxicity information available for DPNB. It has not undergone formal evaluation for id entification as a TAC. There is no expected health risk from the exposure to the CO 2 used in the Solvair technology.

Fire Hazard Considerations

The alternative dry cleaning technologies listed in this fact sheet, with the exception of water-based and

CO 2 cleaning technologies use solvents that may be reg ulated by local Certified Unified Program Agencies (CUPA) because of their flammability and/or combust ibility. CUPA contact information may be found on t he following website: http://www.calepa.ca.gov/CUPA/Directory/default.asp x

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More information

More information on the alternative technologies ma y also be obtained from the following website: www.arb.ca.gov/toxics/dryclean/dryclean.htm . This website contains regulatory information and formal rulemaking documents. For more information on the status and requirements of the amended Dry Cleaning Air Toxic Control Measure, please contact one of th e following Air Resources Board staff.

Mei Fong Sonia Villalobos Hafizur Chowdhury (AB 998 Program) Phone: (916) 324-2570 Phone: (916) 327-5983 Phone: (916) 322-2275

Alternately, you may email questions to dryclean@arb.ca.gov

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