Dry Cleaners Pollution

Dry cleaner establishments are quite common in urban settings. And so is the contamination that is associated with dry cleaning activities. Such contamination may pose serious health risks due to its nature and resistance to environmental degradation. Specifically, chlorinated solvents (especially PCE) are associated with dry cleaning activities. Such chemicals are toxic, mobile in the environment (especially through their volatile nature), and the chemical pollution they create may persist for decades due to their resistance to degradation.

Historically, other contaminants have been associated with dry cleaning activities such as petroleum based solvents. The first recorded use of an organic solvent (spirits of turpentine) to clean clothing was recorded in 1690.

While modern equipment and preventive measures did considerably reduce the occurrence of accidental spills and leaks at dry cleaning locations, the legacy of decades of dry cleaning activities is still felt today. Thus, if you are or have been living within a block from a dry cleaning establishment you may be at risk to overly a contaminated groundwater solvent plume, from which solvents will evaporate and intrude in your breathing air (a phenomenon called vapor intrusion). If this is the case, you may be evaluated for possible pollution compensation benefits.

Tens to hundreds of million of gallons of chlorinated solvents are used every year. The main mechanism through which contaminants are introduced into the environment from dry cleaners is leakage through a sewer line, according to a recent Regional Water Board study (Izzo, 1992). The following main contaminants (along with their degradation products) are usually associated with dry cleaning activities (all are volatile halogenated organic compounds):

• Pollution with perchloroethylene (PCE)
• Pollution with Trichloroethylene (TCE) – which is also a degradation product of PCE
  • cis-1,2-Dichloroethylene (cis-1,2-DCE) – which is a degradation product of both PCE and TCE – the main degradation product of anaerobic dehalogenation of TCE, which is the degradation product of anaerobic dehalogenation of PCE
  • trans-1,2-Dichloroethylene (trans-1,2-DCE) – which is a degradation product of both PCE and TCE
  • Vinyl chloride (VC) – which is a degradation product of both PCE and TCE 1,1,1- trichloroethane (1,1,1-TCA) - marketed as a dry-cleaning solvent (Dowclene LS®).
  • 1,4-dioxane – an additive (inhibitor) usually added to 1,1,1-TCA

Other pollution contaminants that were historically associated with dry cleaning activities include:

• Carbon tetrachloride
• Freon 113 (1,1,2 trichloro-1,2,2-trufluoroethane also known under the commercial name of Valclene – for dry cleaning use)
• Stoddard solvent
• Kerosene
• Mineral spirts

Please note that the historically associated contaminants may still be present in the environment at or close to the historical release area.

More recently, petroleum solvents started to be introduced in dry cleaning, little by little replacing chlorinated solvents. For example:

• petroleum base solvent manufactured by Exxon Chemicals in 1994, namely DF-2000™ - a high flashpoint synthetic paraffin;
• dipropylene glycol tertiary-butyl ether (commercial name of Rynex™ )– first introduced as a dry cleaning solvent in 1999;
• a mixture of isoparaffinic hydrocarbons, hydrofluoroethers and perfluoroisobutylethers (commercial name PureDry™)
• propylene glycol-ether based solvent (commercialized starting 2004 as Impress™)
• n-propyl bromide (with a commercial name DrySolv™) first marketed as a dry cleaning solvent in 2006;

According to a recent study (HSIA 1999) dry cleaning still accounts for 36% of PCE usage in the U.S. A. (HSIA, 1999). However, with more and more alternative safer chemicals on the market, a total replacement of PCE in dry cleaning operations is expected by 2020.