WHAT ARE PHOSPHATES
Phosphates in Everyday Living
Phosphorus is one of the most common elements in our environment and is essential to human, animal and plan life. Phosphorus is present naturally in food, water and even human bodies. In your body, phosphorus is present in your genes, teeth, and bones — even your muscles work because of the phosphorus in adenosine triphosphate.
Today, phosphorus is an important part of many of the products that are indispensable to modern living and good health. A single phosphorus compound can be used in a broad range of applications, including pharmaceuticals, personal care products, industrial & institutional cleaners and other technical uses, such as in fire extinguishers.
Depending on the application, a higher grade form of the ingredient is used. For example, a technical grade form of sodium tripolyphosphate (STPP) functions as a critical ingredient in industrial & institutional detergents while a higher, food-grade form is used as a tartar control agent in toothpaste and mouthwash. Likewise, a food-grade form of tricalcium phosphate (TCP) is used to provide the essential elements calcium and phosphorus in dietary supplements, while a pharmaceutical-grade form is used as inert ingredients in prescription and over-the-counter drugs.
When calcium is added to phosphorus compounds, we get products such as dicalcium phosphate, which is used as a polishing agent in toothpaste, and tricalcium phosphate, which is the conditioning agent in salt that keeps it flowing freely out of the tube.
Phosphate products are a significant part of everyday living. In addition to their versatility, government authorities also recognize them as safe for worker exposure and handling and for use in the home.
In many bodies of water, phosphorus is a limiting nutrient and controlling its level is an important step in preventing eutrophication, or an overabundance of nutrients (see here for additional information). In most areas, a majority of the phosphorus comes from the environment itself, and only a fraction, about a third, comes from consumer products.
There are a few characteristics that define phosphate properties, mainly molecular structure and pH (generally in a 1% solution). These determine the functionality of phosphates, which in turn determine how phosphates are used. They can contribute buffering strength, sequestering (or chelating) power, dispersion and absorptive capabilities, and solubility. Phosphates are usually used as compounds of phosphate ions in combination with one or more common elements, such as sodium, calcium, potassium, and aluminum.
Phosphates are usually used as compounds of phosphate ions in combination with one or more common elements, such as sodium, calcium, potassium, and aluminum.
Phosphates are classified into several primary groups based on the number of phosphorus (P) molecules. Each of these groups have functional properties ideal for many applications.
Orthophosphates Buffering – detergents
Pyrophosphates Sequestering – water treatment, metal cleaning
Tripolyphosphates Dispersant – meat processing, dish detergent
Polyphosphates Dispersant – kaolin production
Number of P Atoms | Ion | Usual Name |
1 | PO4-3 | Orthophosphates |
2 | P2O7-4 | Pyrophosphates |
3 | p3O10-5 | Tripolyphosphates |
> 3 | PnO(3n+1)-(n+2) | Polyphosphates |
Phosphate salts are retrieved from naturally occurring minerals, which are mined, refined, and purified for use in many applications. Phosphoric acid is produced starting with naturally-occurring phosphate ore mined around the world. As phosphoric acid, it can be combined with other elements such as calcium, potassium and sodium into “salts” of orthophosphates. Depending on the application, the orthophosphates can be used in that form, or converted by heat into the groups of products described above. To give a clear picture of the vast areas of phosphates uses, the following list details many products that contain phosphates or require phosphates during their production.