What are phosphates and why is phosphate free dishwasher detergent better for the environment?

Dishwasher detergents are often advertised as “phosphate free” or the packaging will declare that they are free from phosphates. Most of us realise that must be a good thing, but did you ever wonder what phosphates actually are? Read on to find out.

What are phosphates?

Phosphates are a naturally occurring form of the element phosphorus, which is present in our environment and occurs all around us. However, the inorganic chemical phosphate is not identical to the element phosphorous. More specifically, phosphate is a salt of phosphoric acid. Inorganic phosphate rocks are mined to extract phosphorus as a crop fertiliser in agriculture. It encourages plant growth, cell division and photosynthesis. Phosphates are formed when phosphorous combines with other elements and function differently. Various phosphates have been used in consumer products, such as as toothpaste, paint, laundry and dishwasher detergents.

Why were phosphates in dishwasher detergent?

About 5% of the phosphate mined worldwide was used in detergents until quite recently. In dishwasher detergent, phosphates served to bind calcium and magnesium and suspend other particles, helping remove them from dirty dishes in the wash. They also soften water, preventing limescale in the dishwasher.

Are phosphates toxic or harmful?

As phosphates are found everywhere, including in our food and within our bodies, they are not toxic or harmful to humans. In fact, if your doctor detects a phosphate deficiency, you will be prescribed supplements to regulate your phosphate levels. The same goes for the environment: phosphates are nutrients that encourage plant growth and have no adverse effects on plants or animals, per se. If phosphates are neither toxic or harmful to humans, nor to the environment, why have they been banned from dishwasher detergents in most countries?

Why were phosphates banned?

Phosphates have been banned across the USA and the EU, as well as in many other countries. Despite the fact that they are not toxic or harmful to humans, their presence in waterways can disturb the balance of aquatic life forms. As a fertiliser, phosphates cause rapid algae growth. The so-called algae bloom has an adverse effect on other organisms living in the water. Most waste water treatments plants can't fully remove phosphates from household waste water, so some of it inevitably ends up in natural waterways. Countries that banned phosphates were hoping to limit algae bloom and prevent excess nutrients from polluting rivers and lakes.

How does phosphate free dishwasher detergent work?

Somat dishwasher detergents are all phosphate free, according to EU regulations. All products were re-formulated to provide the same cleaning qualities without phosphate as an ingredient. Customers in soft water areas are unlikely to have noticed a change, while customers in hard water areas may now need to use more dishwasher salt. In the first product comparison of dishwasher tabs after phosphate was banned from detergents in the EU, Germany's biggest consumer product testing institute “Stiftung Warentest” found that Somat Gold was the test winner and performed better than all other products, even without phosphates.

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