Eco labelling and eco claims
Eco labels, wording and certifications you can look out for on washing-up liquid include vegan, organic and cruelty free. There may also be eco claims such as 'free from ...', where the thing to be avoided may be palm oil, microplastics or toxic chemicals.
Given that washing-up liquid finds its way down into the drains and eventually into our waterways, you might think it self-evident that these products should not contain substances that could harm the environment. But most mainstream washing-up liquids contain petrochemical surfactants, whose biodegradability is questionable, and synthetic fragrances.
We've looked at some of the common but potentially harmful ingredients you may find in washing-up liquid, and highlight which brands do or don't use them.
We rated companies more highly if they explicitly excluded certain ingredients that are harmful to human health and the environment. These toxic ingredients are triclosan, phthalates, parabens, and formaldehyde. There are other potentially harmful ingredients, but we think that if a company has excluded these four, it’s a good indication that they’re likely to prohibit all of the most toxic ingredients.
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 palm or coconut oil, 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. Petroleum-based surfactants can pass this test.
Companies such as Bio-D, Greenscents and Sodasan use only plant-based surfactants which are readily biodegradable meaning that they break down completely within a short period. As plant-based surfactants may be derived from palm oil, it’s important to check how companies are sourcing this.
PVA and microplastics in detergents
The harmful ingredients category gave points to companies for excluding microplastics. Microplastics can be harmful to human and animal health. They can be both solid and not biodegrade, or liquid and biodegrade poorly, and we looked for companies to exclude both.
There is some disagreement over whether polyvinyl alcohol (also known as PVA and PVOH) is really biodegradable and the extent to which it is harmful. But the Beat the Microbead campaign includes PVA in its red list of ingredients found to contain synthetic polymers which are commonly considered to be microplastic ingredients.
The NGO Environmental Coalition on Standards (ECOS) is campaigning against the use of biodegradable plastics, stating that they
“can present similar hazards in the natural environment to plastics, and the testing methods for biodegradable plastics do not yet reflect realistic use or existing environmental conditions.”
Ruta Almedom, Head of Science at CodeCheck, told us: “PVA can't be considered readily biodegradable. The method often used by companies to claim biodegradability only works under specific circumstances, which do not reflect environmental reality. The often-used Zahn-Wellens test (OECD 302) shows if a substance is ‘inherently biodegradable’ – meaning it is not persistent. However, this does not prove that this substance is also readily biodegradable in the aquatic environment.”
We therefore deducted points from companies that were using PVA. Brands affected were: Astonish, Bio-D, Homethings, Smol, and Suma. Others, Attitude, Kit & Kin and Splosh also lost marks as they sold dishwasher tablets in "water-soluble" wrappers and we assumed that these were made from PVA.
Homethings had a page on its website discussing the PVA debate, though did advertise its products as “plastic free”.
Other companies found to be using liquid polymers on the Beat the Microbead red list were Ecozone, INEOS, and SC Johnson (owner of Ecover and Method).
Fairy (Procter & Gamble) also scored 0 points in the harmful ingredients category, with Unilever (Persil), and Splosh also receiving low scores.
Palm oil in washing-up liquid
Palm oil is a controversial ingredient used in many products, with links to environmental destruction and workers' rights abuses.
Some people seek to avoid any products with palm oil, and some people look for 'sustainable' palm.
Since 2021, when we made our palm oil rating stricter, no large companies using this versatile ingredient have been able to score well in this category. Even those that have all palm ingredients certified and are publicly tracking grievances raised in their supply chain, as well as disclosing which producers they source from, still fall short. We have yet to find a producer list that doesn’t include producers known to have ineffective NDPE measures, which stands for ‘No Deforestation, No Peat and No Exploitation.’
This was the case for two of the biggest companies in these guides, Procter & Gamble, and Unilever, which were also found to have serious third-party criticisms related to their palm oil supply chains and lost points for this.
How do brands rate for palm oil?
Greenscents was the only company which was completely palm free.
Most companies in our detergent guides did have all their palm ingredients certified, including all or most of the derivatives.
We applied the following rating for palm oil if fully certified:
- brands with a turnover over £100m a year scored 40 (out of 100)
- between £10m-£100m scored 60, and under £10m scored 80.
Companies which did not meet our usual criteria but had taken some action on palm ingredients scored 20. This included: Astonish, Kit & Kin, and McBride (Clean n Fresh, Surcare).
Companies which lacked information on palm oil
A number of companies had a lack of information on palm but were using ingredients which could be derived from palm, and thus scored 0 (out of 100) for this category. This included new brand to this guide Homethings.
Attitude had no information on palm oil on its website. Ecozone had a palm oil free icon, but this was not on all products. Ineos’s latest report to the RSPO was incomplete, with no figures for palm usage. Its previous report showed only 16% as certified. Fairy's owner Procter & Gamble also scored zero points for this category.
For more information on palm oil and what ingredients to look out for see our separate palm oil page.