Dishwasher Detergent

Which is the most eco friendly dishwasher detergent? 

In this guide to dishwasher detergents we review not only what's in the product, and who makes it, but which product type is the most eco friendly and sustainable.

We rate and review some of the big brands like Fairy and Finish, popular high street eco brands like Ecover and Method, and also independent green brands like Greenscents and SESI.

With scores ranging from 5 to 95 (out of 100), what you use to do the dishes with could be an easy quick win to swap in a more eco friendly brand. 

If you don't use a dishwasher very often, check out our guide to washing-up detergents where we also discuss how to do the dishes more efficiently and effectively. 

Which is best: tablets, pods, powder or liquid?

If you use a dishwasher, the most difficult decision may be less about finding an eco brand and more around product type.

Pods, tablets, powder and liquid are all different routes to the same end – clean dishes. How has it got so complicated, and why do we need so many options?

The answer is all of these forms of dishwasher detergent have their pluses and minuses. Some are better for minimising transport CO2 emissions, some better for recycling, and some are safer when it comes to pollution and toxics.

Powder and then tablets seem to be the best options, and there are refill options for both of these formats. Powders avoid the issue of the PVA wrapping of tablets. If we were to recommend avoiding any, it would probably be pods.

Dishwasher tablets

Tablets are popular among leading brands but also smaller eco ones. Astonish, ATTITUDE, Bio-D, ecoleaf, Ecover,
Ecozone, Finish, OceanSaver, Smol, Sodasan, Sonnet and Splosh all use tablet form.

Tablets are compact, resulting in less carbon emissions from transportation. They’re convenient to use and store.

However, tablets tend to be more expensive than liquids or powders and they often come individually wrapped.
The wrapping of most tablets and pods, including the eco kind, is usually made from polyvinyl alcohol (PVA or PVOH), a synthetic polymer made from fossil fuels. Debates appear to be ongoing about how biodegradable PVA is. See the pods section below for more on this.

It appears that dishwasher tablets require a significantly thinner PVA wrapping in comparison with pods, which require a much bulkier casing to contain liquids.

However, we did not recommend any tablets because of the issue of PVA so even though companies like Bio D and Ecoleaf (Suma), who only makes tablets and not loose powder, score highly, we did not recommend these products.

Dishwasher pods – are they bad for the environment?

Pods, also known as packs or liquitabs, are compact, saving on CO2 emissions through transportation and saving space in your cupboard. They’re also generally mess-free. However, like tablets, pods often involve a lot of packaging and are more expensive than alternatives.

The PVA that pods are encased in is promoted as 100% water-soluble and biodegradable. A study from March 2021 into PVA used on dishwasher pods stated that it is biodegradable and “there is no concern for persistence or accumulation in the environment.”

But a preliminary study by Arizona State University into the PVA used on dishwasher pods published in April 2021 suggested that "about 4% of the PVA from detergent pods is discharged undigested in treated water, while 65% ends up in sludge” that may end up in landfill, applied to agricultural land or incinerated. The study's author suggests it could harm aquatic ecosystems.

According to the Plastic Pollution Coalition, "Pure PVA doesn’t easily break apart and must be diluted by degradable plant starches and proteins to even appear to dissolve. Think about what happens when you mix salt with water: Just because you can’t see all the tiny grains of salt in the water as they dissolve doesn’t mean the salt doesn’t still exist"

Are dishwasher pods a hazard to children?

Pods also contain highly concentrated caustic detergent – making them hazardous to children and animals should they be ingested. They are often colourful and look a bit like sweets.

A 2016 article in Emerging Medicine News stated “The thin water-soluble packaging material is fun to touch but easily penetrated by a child's fingers, teeth, and saliva. [...] Unlike the old-fashioned granular and liquid detergents that usually produced only mild irritation, these newer products demand clinical respect and likely a bit more observation time.”

One study showed that in 2012-13 (when pods were relatively new), over 17,000 children aged under 6 had been poisoned by the pods: 4.4% were hospitalised, and 7.5% experienced moderate or major medical outcomes.

Due to PVA use, and the risk they cause to health if accidentally ingested, plus the high price tag, pods seem like the least attractive option for dishwasher detergents.

Method offers dishwasher pods. Fairy and Finish sold ‘dishwasher tabs’ which appear to be a combination of a
tablet and a pod (a solid tablet with a liquid capsule on top).

How toxic is dishwasher detergent?

Chlorine bleaches

In terms of pollution and toxins in the home, the chemicals present in dishwasher detergents can enter the body via two primary routes: inhalation of the steam released when a dishwasher is opened after a cycle, or residue left on the ostensibly clean dishes following washing.

Chlorine is sometimes used as a bleaching agent in dishwasher detergents. According to Pat Thomas writing in the Ecologist, “some automatic dishwashing detergents contain dry chlorine that is activated when mixed with the water in the dishwasher. This means that when you open the dishwasher, chlorine fumes are released in the steam that leaks out. These can cause eye irritation and difficulty breathing, especially for those with respiratory problems.”

Brands that stated that their dishwasher detergent didn’t contain chlorine included Method, SESI and Sodasan.

Phosphates

Since 2017, the EU severely limited the amount of phosphates permitted in household dishwasher detergent to no more than 0.3 grams per standard dose. The ban was postponed by two years because of lobbying by phosphate manufacturers and dishwasher detergent producers.

Phosphates in waterways can cause algal blooms and plants that stifle aquatic life and can lead to ‘dead zones’. Some manufacturers, like Bio-D, have been phosphate-free since they started making dishwasher detergent.

Brands and harmful ingredients

We expect companies to show a good approach to harmful ingredients by restricting the use of harmful substances including triclosan, parabens, phthalates and formaldehyde. Our harmful ingredients rating also assesses their approach to microplastics and poorly biodegradable liquids polymers. 

The following brands scored a top score of 100% for their approach to harmful ingredients: 

• Fill Refill
• Greenscents
• Miniml
• SESI
• Sonett

80 marks were received by Bio D, OceanSaver, Smol and Suma, which had good policies apart from the fact they used poorly-biodegradable liquid polymers. Attitude also scored 80 as it used 'water soluble' wrappers on its dishwasher tablets which were assumed to be made from PVA, considered to be poorly-biodegradable. 

The following received the worst rating possible, of zero marks, in the harmful ingredients rating: Ecozone, Fairy and Splosh. Ecover and Method also received 0 marks, because of their ownership by SC Johnson which has a poor approach to harmful substances. 

Surfactants and biodegradability

‘Surface-active agents’ (surfactants) are the main active ingredient in detergents. They work by keeping dirt suspended in the water. Surfactants can be made from plant oils such as coconut oil, or sugar, or can be synthesised from waste materials from the petroleum industry. EU law requires that surfactants used in domestic detergents must be aerobically biodegradable (it will biodegrade if oxygen is present) and break down by 60% within 28 days.

The main surfactant used by the detergent industry is LAS (Linear Alkylbenzene Sulfonate) which is derived from crude oil and is ‘ultimately biodegradable’ but not ‘anaerobically biodegradable’ (i.e., it will not biodegrade unless oxygen is present). 

The most animal-friendly dishwasher detergent

Six brands received full marks for their overall approach to other animals. 

Brands that scored 100 for their approach to animals, which includes both their use of animal derived ingredients and the stringency of their policies against animal testing, were: 

• Astonish
• Bio-D
• Fill Refill
• Greenscents
• SESI
• Smol
• Splosh

Vegan dishwasher detergent brands

Brands in this guide that either marketed themselves or were certified as vegan, or confirmed they didn't use any animal derivatives in their products, included: 

• Astonish
• Bio-D
• Fill Refill
• Greenscents
• Miniml
• OceanSaver
• SESI
• Smol
• Splosh

Cruelty free dishwasher detergent

Several brands received full marks for their policies that aim to reduce the risk of animal testing in their supply chains, including: Astonish, Attitude, Bio-D, Fill Refill, Greenscents, SESI, Smol, Splosh.

While most brands in the guide have vague statements against testing their products on animals, the best brands ensure that they don't buy ingredients from suppliers that have recently tested on animals. Read more about what makes a meaningful no-animal testing policy in our introduction to animal testing.

Although animal testing for finished household products is banned in the UK, lots of companies still use ingredients that were tested on animals by suppliers. If you want avoid animal testing, we’d advise only buying from companies that ensure ingredients they source aren’t tested on animals.

Animal-friendly brands owned by unethical parents

Ecozone is fully vegan and had stringent anti-animal testing policies, but is now owned by a parent company that had investments in healthcare including "drug discovery". This is a sector known for likely risk of animal testing and use of animal derived ingredients, and the parent company didn't seem to have published policies around these issues.

Method and Ecover are vegan and have strong policies against animal testing, but they are owned by SC Johnson, which faces a boycott call by Naturewatch due to its involvement in animal testing. 

The poorest scorers in this guide regarding their approach to animals were Clean N Fresh, Fairy and Finish. 

Fortunately, lots of new eco-brands have emerged to meet the demands of consumers who want clean dishes and a clean conscience. 

Our guide to dishwashers found that a growing number of households now have a dishwasher, and that they are often the more environmental choice for doing the dishes.