After the Second World War, consumers demanded faster turnaround. To meet this, the industry decentralized. The introduction of perc helped: here was a solvent which was non-flammable and safe to handle, and which used equipment economical enough to be installed in the neighborhood drycleaning shop. Same-day service became a reality.

Since that time, perc drycleaning has been able to carry drycleaners through a variety 
of changes in fashion -- even including the polyester leisure suit. The 1990s have brought a new health and environmental challenge. New methods of tracing extremely small quantities of chemicals in the environment -- in urban air, groundwater, soil and the atmosphere of both the workplace and the home -- have led to stringent laws governing waste emissions and waste disposal. And they have led to consumer advocacy groups who call for no trace chemicals in the environment.
Advantages of perc;
     Perchloroethylene has been the principal drycleaning solvent for a number of years becaues;

• Its high solvency (KB value of 90) dissolves most of the oils, grease and fats the drycleaner is faced with. Detergents and spotting chemicals have been developed for the other stains and soils.
•  Perc's low viscosity (0.84 centipoise) and low surface tension (32 dynes/cm) allow it to penetrate fibers rapidly to dissolve soils.Because perc is hydrophobic, it doesn't swell the fibers.
• The high density of perc (13.5 lbs./gal.) not only facilitates mechanical action in the washing cycle, it also helps the separation of solvent from water in the recovery process.
•  Its high evaporation rate (1.5 compared to n-butyl alcohol, the standard) provides for reasonable drying times at moderate temperatures. Most importantly, it was perc's virtual non-flammability that led to its wide use when decentralized drycleaning plants became standard in the industry after World War II.

The key concerns are, as with any chemical, understanding the hazards. In this case understanding the toxicity issues and whether it is or is not a human carcinogen. To address these hazards, a perc-based process has to control emissions so that employees and the public get as little exposure as possible, thus minimizing the potential risk.

As far as toxicity is concerned, there is virtually no risk to employees or customers of a drycleaning plant when the solvent is handled properly. Most current regulations are based primarily on toxicology studies, including cancer studies, which were done on laboratory animals. However, different species of animals, including humans, metabolize chemicals differently. Thus, one cannot assume that a cancer effect in one animal species will predict cancer in another species without
understanding the metabolic processes in the species.

Perc producers, trade associations, industry experts and many independent scientists agree that when you consider all the available scientific evidence, there is no cancer risk to humans when perc is used properly. In fact, the science advisory board of the U.S. Environmental Protection Agency (EPA) has concluded that "there is no compelling evidence of human cancer risk" for perc.
The practice of including an assessment of the metabolic differences of species is now acknowledged by regulators, and it is just now being included in the process regulators follow for risk assessments.

Producers of perchloroethylene, committed to the continued safe use of this solvent, support the industry in two ways. They are funding additional long term health studies which will ultimately help answer these complicated questions. They are also working with regulatory agencies to make sure that the most advanced scientific methods are used to evaluate perc.

 Janet Hickman is Dow's drycleaning industry development leader and perchloroethylene product steward. This article is based on a presentation she gave in Arizona last year. It was originally published in the summer 1997 issue of Dow's Spot News.

Alternative #1 - Green Clean
 

• A pleasantly scented, all-purpose cleaner designed for the rapid removal of grease and other heavy soils. It can be used right out of the bottle or diluted for milder jobs. It instantly penetrates greasy and oily surfaces, providing powerful emulsifying ingredients that chemically soften and dissolve the deposits, making them easy to remove. The safer, effective, alternative to toxic cleaners, bleaches and solvents. It's non-corrosive and very economical to use (Calgon Products, 1997).
• Grants Notes; Green Clean is a considerable amout of addition work in that employees must manually apply the cleaner. However, including the additional labour, Green Clean is more economical.
• View MSDS

•   Dryel uses biodegradable cleaning agents. Additionally, the dryer bag is

  reusable and the refill packaging is made from 100%- recycled
  paperboard. The plastic lid is also made from 100%- recycled plastic
  (PET). The Dryel Bag is designed for multiple uses (up to 20 cycles). To reduce
  waste, we've designed a consumer-friendly refill which uses 49% less
  packaging than the primary kit and is made from 100% recycled fiber.
  We've also found that many consumers have used the bag for trash
(Proctor and Gamble, Dryel, 1998).
• Grants Notes; It is important to note that this is an 'at home' Drycleaning product. This product has not yet been on shelves for a full year, and is still in it's 'personal use' trial stage. MSDS sheets are not available at the Proctor and Gamble web-sight. Although this product is quite new, it appears to have excellent potential. Proctor and Gamble has conducted extensive research and placed a great deal of effort into maximizing the biodegradability of the product.

• Below 88 degrees Fahrenheit, at less than a thousand pounds of pressure, carbon dioxide gas (CO-2) becomes a liquid.Over a 25- to 30-minute period under laboratory-controlled conditions, the reusable clear liquid lifts stains from fabric. "It's environmentally friendly," says Los Alamos researcher Craig Taylor, "because CO-2 doesn't react with anything." different fabrics, including whites and colored

garments, can be cleaned at the same time because the CO-2 do not act as a color-removing bleach (CNN,Pressing Issue, 1996).
• Grants Notes; Although, this product promises near miracles, and is said to be environmentaly friendly, this is highly questionable. Logic would dictate that the usind carbon dioxide in its liquid state may present environmental problems. More information regarding disposal, treatment and safety precaution is required to make a clear judgement.