A world of detergents

How much phosphate?
Phosphates—compounds containing phosphorus—are found in detergents, laundry powders, liquids, and shampoos (as well as in fertilizers, animal excrement, urban runoff, and sewage). In detergent products, they are used as "builders" to boost the cleaning power of the surfactant by softening water (they react with ions in hard water that interfere with cleaning), increasing alkalinity, and helping suspend the dirt in water.

Phosphorus is a naturally occurring element found in all living things. In water systems it acts as a nutrient, encouraging the growth of plants. However, too much phosphorus in water systems encourages excessive growth of algae and weeds, robbing less aggressive plant life and animal life of oxygen, resulting, ultimately, in lifeless streams and rivers.

You can choose low-phosphate products, which contain less than 5 percent phosphate, or ones without phosphate, although information about other ingredients in the product is often lacking.

Biological or nonbiological?
Biological detergents contain stain-fighting enzymes that aid soil breakup. Nonbiological laundry detergents may be less irritating to those with sensitive skin than ones containing enzymes. If you suspect the many additives in laundry detergents are the problem, try pure soap flakes. Soap-based powders may contain additives but are usually formulated to be milder than standard detergents.

Detergent format and quantity
• Concentrated powders omit the fillers that bulk out some powders. Obviously you need less, but try using less of any detergent, especially with lightly soiled items.
• Liquid detergents are easy to dissolve.
• Tablets make dose measurement foolproof.
• Soap is available in flakes and as a solid bar.
• Some stains and types of soiling may call for more detergent, not less. For instance, thick creams and heavy perspiration decrease a detergent's action, as does hard water.

Allergy alert in the laundry
Ingredients in detergents, fabric softeners, and soaps can cause skin irritations and other allergic reactions. Some people are allergic to the solvent 1,1,1-trichloroethane, which is used in stain removers. It has a strong odor and can cause sneezing or a tightening of the chest in people with respiratory allergies.

If you or someone in your household is prone to allergies, take these precautions.
• Consider using a nonbiological detergent.
• Rinse clothes extra carefully, perhaps by using the rinse cycle twice.
• Before wearing new clothes wash them to remove excess factory finishes.
• Wear gloves when hand washing.

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