Phosphates are a group of ingredients derived from phosphorous, which have been used in many detergents to improve cleaning performance. Phosphorous can cause environmental damage when it's released into waterways, including contributing to algae blooms and death of aquatic life. We choose to keep phosphates out of our products.
Phosphates have long been used in agriculture as nutrient-rich fertiliser, and are typically derived from phosphate rock (a finite resource, which may soon be depleted). In laundry and cleaning products, they're used as ‘builders’. Builders reduce water hardness (remove metal ions such as calcium and magnesium from water), and help bind and capture removed soil to prevent it from redepositing during the wash. A common phosphate used in detergents is sodium tripolyphosphate (STPP).
When used in detergents, phosphates are considered to be a low hazard to human health, however their use can lead to nutrient pollution in the environment. Awareness of this issue developed in the 80s and 90s, and action has been taken by some governments to ban the use of phosphates in detergents, including the EU and United States. When entering waterways, phosphates can promote rapid increase in some algae populations or even ‘bloom’ events. Algae overabundance absorbs a higher proportion of oxygen from the water, which in turn reduces the amount of essential oxygen available to other aquatic life. The problem with disturbing the marine ecosystem in this way becomes much larger than just killing off a few fish. Marine food webs are far more intricate and delicate than those on land, which means that even the smallest changes in dynamics can cause rapid and hugely detrimental consequences. Phosphate alternatives such as zeolites, are available to detergent manufacturers who wish to avoid this type of damage and take responsibility for their environmental impact.
Chemical class: Phosphorous Compounds
Chemical structure depicted: Trisodium Phosphate, Sodium Tripolyphosphate, Tetrasodium Pyrophosphate
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EU Environment Directorate. (2002). Phosphates and Alternative Detergent Builders - Final Report. https://ec.europa.eu/environment/water/pollution/phosphates/pdf/phosphates.pdf
National Center for Biotechnology Information (2022). PubChem Compound Summary for CID 24243, Trisodium phosphate. https://pubchem.ncbi.nlm.nih.gov/compound/Trisodium-phosphate.
National Center for Biotechnology Information (2022). PubChem Compound Summary for CID 24455, Sodium tripolyphosphate. https://pubchem.ncbi.nlm.nih.gov/compound/Sodium-tripolyphosphate.