Dry Cleaning

There are some new drycleaning stores opening up in North America that advertise themselves as "green" or "organic." What do these terms mean exactly?

Traditional drycleaners use perchloroethylene, also known as tetrachloroethylene, perc, PCE, ethylene tetrachloride, or tetrachloroethene. The chemical formula is Cl2C=CCl2. There are a number of different chemical processes used for making it. According to NIOSH, or the National Institute for Occupational Safety and Health, overexposure causes irritation, nausea, vertigo, incoordination, headache, somnolence, skin erythema, or liver damage. According to the Merck Index: "This substance is reasonably anticipated to be a human carcinogen."

OK, so we know it's bad for the workers who use it, but how bad is it for us? Since there is a lingering scent, there must be lingering chemical on the clothes. I have incredible sensitive skin, but I have never had a reaction to drycleaned clothes, while I've had skin reactions to some kinds of laundry detergent. Nonetheless, whatever the level of your exposure, this is the kind of chemical that gets stored in your fat, can linger in the body for a long time, and can get passed on to your offspring. We are exposed to those kinds of chemicals all too often, who wants one more, even if the effect is not immediately obvious?

According to the EPA, "[perchloroethylene] can be added to aerosol formulations, solvent soaps, printing inks, adhesives, sealants, polishes, lubricants, and silicones. Typewriter correction fluid and shoe polish are among the consumer products that can contain PERC." There have been many incidences of soil contamination from dry cleaning plants. Perchloroethylene spills are particularly problematic because it does not bind soil, but is soluble in water, so it can get into groundwater supplies or evaporate into the air.

So, when an "organic" drycleaner opened in my neighborhood, at first I was happy to see an alternative, but then someone at work mentioned that although it is more expensive, this might not be any better. Further reasearch indicate that the solvent used is petroleum based, and is manufactured by Exxon-Mobil. It turns out that this was the most common drycleaning solvent until 1921, when perchloroethylene was invented. The health and environmental effects of petroleum are well-known. It is called "organic" based on the chemical definition of organic, which means that it is carbon-based. It bears no relation to the meaning of "organic" we have come to associate with certain kinds of food.

"GreenEarth cleaning" uses a silicone-based solvent called D-5 (manufactured by Dow-Corning) that attaches to the grime embedded in fabric and removes it when the solvent is extracted. NPR's Morning Edition reported on this on January 10th. A study on rats found that it caused cancer and liver damage. The EPA says there is not enough information to regulate it, therefore they don't need to.

So, why do we need to dryclean anything anyway? These methods actually involve a liquid, so the term "drycleaning" is a misnomer that really just refers to the fact that there is no water used. Water causes plant-based fibers to shrink or swell, and results in the fabric becoming misshapen. It also lingers in the fabric longer before evaporating, weighing it down and stressing the seams. Nonetheless, I have discovered over the years that most clothing with a "dry clean only" label can actually be hand-washed without any noticeable damage. I would be most wary of washing clothes cut on a bias, or things with many layers, like a coat. For those, I wish I could recommend which of the three processes was the safest. We could use some more scientific studies as well as guidance by our regulatory agencies to help us to make an informed decision about these new choices. Meanwhile, I will be skeptical of "organic" and "green" claims.