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 expected all household cleaning brands to have a clear policy against the use of three particularly nasty chemicals – triclosan, parabens and phthalates. In total eleven of the companies rated received our best rating for their toxic chemicals policy. They are: Astonish, ATTITUDE, Bentley Organic, Bio-D, ecoleaf (Suma), Faith In Nature, Fill Refill, Greenscents, Miniml, and SESI.
Synthetic fragrances are used in most mainstream detergents. The word ‘Fragrance’ or ‘Parfum’ on a label represents an undisclosed mixture of various scent chemicals and ingredients, potentially including hormone-disrupting phthalates, synthetic musks, and ethylene oxide. Fragrance mixes have also been associated with allergies, dermatitis and respiratory problems. Alternative products are commonly either fragrance-free or they use essential oils.
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 alternative surfactants used by companies such as Bio-D are plant-based and ‘readily’ biodegradable.
Polymers and plastics in detergents
As well as potential microplastics, there may be liquid polymers in your cleaners. Liquid polymers are not plastics, but they are also poorly biodegradable and remain for years in our ecosystem with unknown consequences
Our rating for microplastics and liquid polymers found the following:
- Liquid polymers found in ingredients: Ecozone, SC Johnson (owner of Ecover and Method).
- No clear statement found about micro plastics and liquid polymers: Astonish, McBride (Surcare), Prism (Eco-Max), Procter & Gamble (Fairy).
- No statement found: ATTITUDE, Easy, Splosh.
- Companies that got a best rating for microplastics and liquid polymers were: Bentley Organic, Bio-D, ecoleaf, Faith in Nature, Greenscents, Miniml, Planet Detox, SESI, Sodasan, Sonett.
Companies which lacked a clear policy around the use of microplastics and non-biodegradable liquid polymers lost half a mark under the Pollution & Toxics category.
Antibacterial washing-up liquids are quite common in the mainstream brands, but they are no more effective against germs, including COVID-19, than standard washing-up liquid and may contribute to antibiotic resistant bacteria.
Palm oil in washing up liquid
Some of the brands we reviewed are completely palm oil free across all products. They were: Greenscents and Planet Detox, with Greenscents certified as palm oil free by the International Palm Oil Free Certification Trademark POFCAP.
Several others (Bio-D, Ecovibe, Faith in Nature, Fill Refill, Miniml, SESI, Sodasan, and Splosh) scored our best rating for stating that all of their palm ingredients, including derivatives, were certified by the RSPO.
Several small or medium companies scored a worst rating if they had no information on palm-based ingredients,
or if they only seemed to use certified palm in one brand but not another, or if they talked about palm oil but not
derivatives: Astonish, ATTITUDE, Bentley Organic, Easy, EcoLiving, Ecozone, and Prism (Eco-Max).
For more information on palm oil and what ingredients to look out for see our separate palm oil page.