Get this: dry cleaning isn’t really dry. Nope, we’re not pulling your (dry-clean-only trouser) leg. Although no water is involved in the process (hence the name), liquid solvents are, and the main one, perchloroethylene, is nasty stuff. Better known as perc, it’s a likely carcinogen linked to a host of other health problems that also contaminates our soil and water.
Of course, the simplest (and probably cheapest) solution is to avoid clothes that require dry cleaning in the first place. These days, there are even machine-washable suits (look for ones that haven't been treated with wrinkle- or stain-repellents, which often use formaldehyde). And many cotton, linen, and silk clothes can be safely hand-washed in cold water even if they say "dry-clean-only."