The reason washing-up liquid is worse for the environment than you think - and what we can do about it

While millions of UK homes rely on washing-up liquid daily - usually sold in single-use plastic bottles - the most pressing concern isn’t the plastic, but what’s inside it. Cleaning experts say many mainstream products contain fossil fuel-derived chemicals known as surfactants, which wash down the drain and end up polluting rivers and seas.

“These surfactants don’t just vanish,” warned sustainability group Sustainably Lazy. “They persist in waterways and can cause real damage to aquatic life.” Ethical Superstore added that common ingredients like sodium lauryl sulfate (SLS), used to create foam and break down grease, are especially problematic, as they linger in water systems and threaten marine ecosystems.

A scientific study published in the Journal of Applied Microbiology confirmed these risks, noting that surfactants can penetrate cell membranes, causing toxicity in marine species. Fish exposed to these compounds have shown gill damage and even loss of eyesight.

The study read: “The use of surfactants in households and industries is inevitable and so is their discharge into the environment, especially into the water bodies as effluents. Being surface-active agents, their utilization is mostly seen in soaps, detergents, personal care products, emulsifiers, wetting agents, etc.

“Surfactants are capable of penetrating the cell membrane and thus cause toxicity to living organisms. Accumulation of these compounds has been known to cause significant gill damage and loss of sight in fish.”

Plastic packaging adds another layer of environmental concern. The UK generates over 170 million tonnes of waste annually, yet less than a third of plastic packaging is recycled. A stark reminder of the problem came in 2018 when the Burnham Coastguard Rescue Team discovered a 47-year-old washing-up liquid bottle still intact on the beach.

Experts and environmental groups are now calling on consumers to switch to eco-friendly alternatives, both in packaging and ingredients, as the new year approaches.