Detergents aren’t soap, although soap is a detergent. The word “detergent” simply means a cleansing substance, from the Latin detergere, to wipe off.
After more than two thousand years of using soap, which is easy to make by boiling up wood ashes with animal fat (don’t you wonder how that discovery was made?), humans finally created synthetic detergents, which in many cases work even better than soap. Today we reserve the word “detergent” exclusively for those artificial chemical concoctions that take up so many acres of shelf space in our supermarkets.
All detergents, including soap, are surfactants, chemical compounds that have the knack of bringing oil and water together. Most dirt adheres to our skins, clothing, dishes and cars by means of a sticky, oily film. Coax the oily film into the water and you have succeeded in removing the “glue” that stuck the dirt to the objects.
But all those colorful bottles and boxes on the store shelves may contain a mad scientist’s laboratoryful of other chemicals besides surfactants. Otherwise, how could the manufacturers keep claiming that their products are any different from or better than all the others?
Here is a list of what may be hiding in your laundry products, household cleaners, soaps, window cleaners, dishwashing detergents and the like, in addition to surfactants. And don’t forget the most expensive ingredient of all: advertising. Lots and lots of advertising.
Acids and alkalis: Acids help to remove mineral buildup, while alkalis attack fatty and oily soils. Examples: acetic acid, citric acid, ammonia.
Antimicrobial agents: Kill disease microorganisms. Examples: pine oil, tricloban, triclosan.
Anti-redeposition agents: Once you get the dirt off, you have to keep it from going right back to where it came from. Examples: carboxymethyl cellulose, polyethylene glycol, sodium silicate.
Bleaches: Remove stains and “whiten and brighten” your clothes. Examples: sodium hypochlorite (chlorine bleach), sodium perborate (“colorsafe” bleach).
Builders: Counteract hard water, which interferes with the surfactant’s performance. Examples: sodium carbonate (washing soda), sodium tripolyphosphate. The latter is one of the notorious phosphates in detergents. If phosphates get into the sewers and then into streams and lakes, they can harm the environment by disrupting the ecological balance.
The phosphates make algae grow in profusion, and when the waters can’t sustain any more algae they die off, which provides a feast for bacteria, which use up oxygen in the water and kill the fish, which makes even more dead bodies for the bacteria to feed on, etc. Because of this, phosphates have been largely eliminated from detergents.
Corrosion inhibitors: Protect the metal parts of your washing machine or kitchen utensils. Example: sodium silicate.
Enzymes: Enzymes are natural chemicals that speed up natural chemical reactions. In laundry products they speed up the destruction of specific kinds of stains, such as grass. Examples: protease, cellulase.
Fabric softening agents: Soften fabrics and control static electricity. Example: quaternary ammonium compounds.
Fragrances: Cover up the smells of all the other ingredients and make you think your laundry is “fresh,” whatever that means.
Optical brighteners: Make clothes look brighter by converting yellow light or invisible ultraviolet light into bluish or whitish light. Example: stilbene disulfonates.
Preservatives: Protect the product from oxidation, discoloration and bacterial attack. Examples: butylated hydroxytoluene, EDTA.
Solvents: Keep all the ingredients dissolved in liquid products. Examples: ethyl alcohol, propylene glycol.
Suds control agents: Control the amount of suds or make the suds keep their “heads.” Examples: alkanolamides and, guess what?, soap. Life in the laundry isn’t as simple as when all we had to do was boil up a nice kettle of goat fat and ashes.
