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24 Jun 2021

Behind the label: what's in your detergents?

From anionic surfactants to zeolites, find out what the ingredients in your washing-up liquid, dishwasher tablets and laundry detergent actually do
Reading washing-up liquids ingredients label

If you found yourself drifting off during chemistry lessons at school, making sense of the ingredients list on that box of laundry powder at home is likely to be a bit of challenge.

But this rundown of some of the most commonly used ingredients in different household detergents will help bring you up to speed with what exactly is in those products and why.

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Anionic surfactants

Surfactants are responsible for the desoiling and degreasing effects of many household cleaning products. They break down grease and help suspend it in the water, preventing it from redepositing onto clothes or plates, allowing it to be easily washed away.

Some examples of anionic surfactants include, sodium laureth sulfate and sodium lauryl sulfate. These surfactants can be derived by refining petroleum or plant-based sources, such as coconut or palm oil.

Non-ionic surfactants

These perform the same function as anionic surfactants, but these compounds lack an electric charge, which allows them to continue doing their job effectively even in hard water.


These are found in bio laundry detergents and dishwasher tablets, and help to break down the starches, proteins and fats that make up the stains on your clothes or dishes.

You'll typically just see 'enzymes' listed, but occasionally the type of enzyme is also there in brackets. Amylase breaks down starches (long chain sugar), protease tackles proteins (subtilisin is a type of protease you might see listed individually), and lipases break down fats.

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These are used in dishwashing detergents because they soften hard water, helping to prevent spotting, while also aiding stain removal. You'll also find them in many laundry detergents.

They've emerged as a popular alternative to phosphates, which were banned in 2017 due to the damage they cause to aquatic life.

Phosphonates are ecologically safer than phosphates, although not without their own issues, and can be used effectively at lower concentrations.

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Oxygen-based bleaching agents

Used in laundry detergents to help remove stains and leave fabrics bright. Through oxidation they break a stain down.


One of the most commonly used preservatives in laundry liquids and cleaning supplies. Its antibacterial properties help to extend the shelf life of the product by preventing them spoiling.

Sodium polycarboxylates

Commonly found in laundry detergents, sodium polycarboxylates are used to prevent dirt from being deposited back onto fabrics once it's been removed.

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Minerals that help soften water so that detergents can work unimpeded. Commonly used in colour detergents, as they can help prevent clothes greying and lessen the risk of colours running.

Phenoxyethanol and benzisothiazolinone

Bacteria can quickly spoil a product. These popular preservatives are added to help extend the life of washing-up liquids and other detergents.


Alpha isomethyl ionone, citronellol, coumarin, limonene and linalool are some of the most common ingredients that give washing-up liquids and laundry detergents their fragrances.

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