An Overview of Phosphates and Their Uses

Three bottles of dish washing liquid
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What exactly are phosphates? Phosphates are chemical compounds containing phosphorus, a naturally occurring mineral, and oxygen, that are used in a wide variety of applications (e.g., cleaning and baking products). Sometimes they include other minerals, such as calcium and sodium.

Types of Phosphates

According to the Phosphate Forum of the Americas, phosphates fall into four major groups (each of which has its own functional properties) depending on the number of phosphorus atoms: orthophosphates, pyrophosphates, tripolyphosphates, and polyphosphates.

Other Names

There are several types of phosphates, but these are the phosphates most often found in cleaning products.

Phosphates used in automatic dish detergents and laundry detergents: Sodium tripolyphosphate (STPP).

Phosphates used in specialty products, such as silver cleaners, and detergents and cleaning products in liquid form for industrial applications: Tetrapotassium pyrophosphate (TKPP). This chemical also goes by Potassium pyrophosphate; Diphosphoric acid, tetrapotassium salt; and Tetrapotassium pyrophosphate according to the U.S. Department of Health Human Services Household Products Database. The CAS Registry Number is 007320-34-5.

Phosphates used in heavy-duty cleaners: Trisodium Phosphates (TSP), Tetra- Sodium and Potassium Pyrophosphates, Sodium Potassium Pyrophosphate

Cleaning Uses

Phosphates are used in automatic dish detergents and laundry detergents to help soften water and remove soil, oil and grease. They also help prevent spotting and film build-up in automatic dish detergents. Due to their ability to cut through soap scum and mineral build-up, they are sometimes used in tile and porcelain cleaning products. In addition, phosphates may be used in specialty cleaners, such as concrete cleaners.

Phosphates have been banned for use in laundry detergents in the U.S. since the 1990s and may soon be banned in Europe, too. With regard to automatic dish detergents, phosphates have also been banned in several U.S. states, but are still allowed in institutional cleaning products.

Other Uses

In addition to cleaning products, phosphates have a dizzying number of other uses. They may be found in water-based paints and coatings, metal polishes, flame retardants, processed foods, personal care products, pharmaceutical products, and more. For example, STPP is used to preserve the moisture and flavor in shrimp and ham.

Product Brands Containing Phosphates

To see if certain products contain phosphates, try searching the U.S. Department of Health and Human Services Household Products Database, the Environmental Working Group's Guide to Healthy Cleaning, the Good Guide, or the Environmental Working Groups Skin Deep Cosmetic Database.


When phosphates are used in food, personal care, and pharmaceutical preparations, they are monitored by the U.S. Food and Drug Administration (FDA). For other uses, such as cleaning products, they are monitored by the Environmental Protection Agency (EPA).

Health & Safety

Phosphates can naturally occur in certain foods, but when they are added to processed foods they can have serious health effects if large amounts are consumed. Lynn Eldridge, The Spruce Expert, notes in her article, "Common Food Additive Speeds Lung Cancer Growth," that phosphate food additives have been shown to stimulate lung cancer development. High phosphate content in processed foods can also affect renal and cardiovascular function.

When phosphates are used in cleaning products, they can also cause health problems. Housekeeping employees in New York medical establishments reported a reduction in symptoms, such as rashes, dizziness, and scratchy throats, once they started using phosphate-free cleaning products.

Environmental Effects

Large amounts of phosphates are regarded as a problem because they enhance algae growth and reduce the oxygen available for fish and plants in streams and lakes.

Green Alternatives

Several manufacturers, such as Seventh Generation, have jumped on board with phosphate-free dish detergents. The problem is, sometimes spotting is still a problem, which is when some green tips and tricks to automatic dishwashing come in handy! Also, instead of using products containing phosphates to remove scale and soap scum, why not just try cleaning with vinegar or making your own vinegar spray?