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How to buy water friendly products

Choosing less polluting and more sustainable products, and then disposing of them safely, can help keep our seas and rivers clean
Karen LawrenceSenior researcher & writer

Every river in England is contaminated by a 'chemical cocktail' of sewage, agriculture and road pollution, according to a parliamentary report from the Environmental Audit Committee. Microplastics, slurry, car tyre particles, oils and wet wipes are also part of the problem, putting human health and the natural environment at risk of harm.

Some of this pollution comes from runoff from agricultural land, roads and businesses, but some of it comes directly from our homes,  caused by the products we use every day in our kitchens and bathrooms.

What we put down our drains really matters. Although it’s not the only cause, wastewater pollution is a contributing factor in 54% of all the English rivers that fail to meet good ecological status. In its most recent report – the annual State of Our Rivers – the Rivers Trust also found that the concentration of toxic chemicals exceeded the safe limit in all of England's rivers.

Choosing less polluting, more sustainable products, and disposing of them safely, can help reduce sewer blockages and water contamination.

Where does wastewater go?

The water we use at home for things like showering, flushing the loo and washing clothes and dishes heads down the drain. Many of us don't think too much about what happens next – but it's the start of a long journey.

As wastewater contains a wide range of contaminants, including faeces, urine, food waste and chemicals from household cleaning products, soaps and shampoos, it must be cleaned thoroughly before it can be returned to natural watercourses. 

First, it's filtered to remove larger items such as wet wipes and sanitary products, leaves and grit. It then goes into settlement tanks where suspended solids, oils and fats are separated out. After further treatment to remove suspended and dissolved organic matter, the cleaned water is returned to local rivers and streams. Some sewage works also apply a higher level of treatment to remove nitrogen and phosphorous, or disinfect water to remove viruses and bacteria.

This system of wastewater treatment should mean that only clean water is released into watercourses; however, it is frequently bypassed by combined sewer overflows, also known as storm overflows, which allow untreated sewage to flow directly into seas and rivers.

Sewage overflows in the UK

There are more than 21,000 combined sewer overflows (CSOs) in the UK. They're a vital part of the network and provide a safety valve to divert excess water and prevent homes and streets being flooded with sewage in case of emergency. 

Water companies are permitted to discharge untreated wastewater through CSOs when the system is overloaded, typically during periods of unusually heavy rainfall or when sewers are blocked. However, although this system is designed for use in emergencies, it is being used with increasing regularity. 

In 2023, water companies emptied untreated sewage into our seas and rivers in this way more than 450,000 times, a 54% increase on the previous year. This was partly down to it being a much wetter year than 2022, but it does also represent a worrying trend.

Not only does it make conditions extremely unpleasant for swimming and other water-based activities, it also threatens ecosystems and affects human health, causing everything from ear infections to severe gastroenteritis.  

Related: Find out how to check if it’s safe to swim at beaches around the UK coastline.

What happens to sewage after treatment?

While the water that's filtered from the sewage treatment plant is sent to rivers and seas, there's also the small matter of the residue left behind – called sewage sludge.

Farmland is the ultimate destination for the majority of the UK’s sewage sludge. According to the water industry, around 78% of the country’s treated sludge – 3.6m tonnes – is spread as fertiliser on hundreds of farms each year. 

Investigators commissioned by the Environment Agency found sewage waste destined for English crops was contaminated with dangerous 'persistent organic pollutants' – including dioxins, furans and polycyclic aromatic hydrocarbons – at levels that may present a risk to human health, as well as the antimicrobial triclosan, which scientists believe may cause antibiotic resistance.

They also found these sludges were widely contaminated with microplastics that could ultimately leave soil unsuitable for agriculture. Microplastics enter the sewage system from washing synthetic clothes, tyre crumb washing off the roads and other sources. 

Sewage treatment works can remove 99% of these microplastic fibres from wastewater; however, having carefully removed them from wastewater, they are then spread across the land where they either accumulate in the soil where crops are grown, or wash off the soil back into rivers.

Drug traces in wastewater

Some substances cannot easily be removed by conventional sewage treatment methods. Both prescription and over-the-counter medications find their way into wastewater. Unused drugs should never be disposed of down the drain; however, medications also enter the sewage system in urine. 

Antibiotics and synthetic hormones (such as contraceptive drugs) have been found in rivers and lakes, and in the fish living there. Increasing levels of synthetic oestrogen in water can trigger a condition known as intersex in freshwater fish, which has caused population decline in some species.

Other chemicals found in sewage include caffeine and ibuprofen. Their effects are not routinely monitored and the full impacts are unknown; however, studies suggest they are harmful to wildlife. There’s evidence to show that just under half of UK rivers could contain ibuprofen at levels that pose a risk to fish.

Three things you can flush

An increasing cause of sewer flooding is so-called 'fatbergs' and other blockages. These are the result of the wrong things – usually non-degradable solids – being put down the toilet, such as wet wipes, sanitary products and other disposable items. These mix with solid fats to create large sewer blockages.

To keep sewers flowing, you should only ever flush three things down the toilet. These can helpfully be summed up as the three Ps – poo, pee and paper (toilet paper, that is). 

While some wipes are labelled as 'flushable', they don't all break down quickly when they enter the sewer system, and may still cause blockages.

Fine to Flush was an official standard identifying wet wipes that could be safely flushed down toilets. However, the certification was removed in March because the scheme was deemed too confusing. Consumers were led to believe that all wipes were fine to go down the loo, and failed to follow packet instructions that only one wipe should be flushed at a time. As a consequence, wet wipes have been clogging up sewers and causing 'wet wipe reefs' in rivers.

fine to flush logo

Chemicals that have an adverse effect in water

Many chemicals are so widespread, it makes them difficult to avoid. But if you're keen to clean up your contribution, these are the ones to avoid where possible. 

Check the ingredients list on your cleaning products, laundry detergent, dishwasher tablets, bath and shower products, and any other products that are likely to end up down the drain.

Parabens

Parabens are a group of compounds widely used as an antifungal agent, preservative and antimicrobial in a variety of everyday products, such as cosmetics, deodorant, face cream, shampoo and toothpaste. An estimated 90% of cosmetic products contain parabens and, for years, they have been considered safe as they are virtually non-toxic. 

However, studies have linked parabens to hormone disruption, reproductive toxicity, immunotoxicity, neurotoxicity and skin irritation. Despite treatments that eliminate them relatively well from wastewater, parabens are frequently detected in surface water, fish and sediments. It's hard to tell whether products contain parabens, so look for paraben-free labelling on the packaging.

Triclosan

Triclosan is an antibacterial agent found in a wide range of household and personal care products – toothpastes, mouthwashes, soaps and deodorants – to offer long-lasting protection against bacteria, moulds and yeasts. Triclosan can affect the body’s hormone system – especially thyroid hormones, which regulate metabolism – and may disrupt normal breast development. 

The EU classifies triclosan as irritating to the skin and eyes, and as very toxic to aquatic organisms, noting that it may cause long-term adverse effects in the aquatic environment. Widespread use of triclosan may also contribute to antibiotic resistance.

Phthalates

Phthalates are a group of chemicals that are most commonly used to make PVC soft and flexible. They are also used in synthetic fragrances, shampoo, deodorant and laundry detergent. 

Unfortunately, they are also hormone disruptors, and phthalate exposure has been linked to early puberty in girls, a risk factor in later-life breast cancer. Phthalates can be dangerous to both ecosystems and humans, and many are not completely removed during conventional wastewater treatment processes.

PFAS

PFAS (perfluoroalkyl and polyfluoroalkyl substances) are a type of man-made microplastic that have been causing concern due to their extreme persistence, mobility and potential to build up inside living organisms. Some have been linked to a range of health problems when found in high doses. 

They have been termed ‘forever chemicals’ as they do not biodegrade in the environment. They've been manufactured since the 1940s, and are now estimated to be in almost every living organism on the planet, including in the bloodstream of nearly every human being. Used for their nonstick, stain-resistant properties, they can be found in everything from clothes and home furnishings to food packaging and cleaning products. 

The issues associated with PFAS are becoming more widely known in the UK, but they are better known in the USA, where they were the focus of a lengthy lawsuit on behalf of people who had become sick after ingesting PFAS in water contaminated by a nearby manufacturing plant. Recent detection of PFAS in UK waters have highlighted the poor removal of PFAS by wastewater treatment. 

Synthetic fragrances

Synthetic fragrances are found in everyday products and often comprise as many as 200 ingredients. 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. Fragrances enter the aquatic environment via wastewater; they have been found to be toxic to aquatic life and can accumulate in the food chain.

Other chemicals to avoid

Other potentially harmful chemicals include stilbenes, used as optical whiteners in laundry products; non-biodegradable surfactants derived from crude oil; and liquid polymers, which are poorly biodegradable and may remain in ecosystems for many years.

How to find eco-friendly cleaning products and toiletries

Look for naturally-derived formulations with ingredients that are readily biodegradable, and choose fragrance-free products or those scented with essential oils. If your local shops don't stock them, online retailers such as Ethical Superstore have a wide range of environmentally friendly laundry, dishwashing and household cleaning products, as well as personal hygiene and beauty products.

Check our reviews to find eco detergents that can match the best for cleaning power – but remember that eco products often don't use optical whiteners, so they may not achieve top marks in tests designed to measure whiteness.

Read more about whether you really need antibacterial handwash, washing-up liquid and laundry products.

Beware of greenwashing. Some manufacturers make unsubstantiated claims about their cleaning products and toiletries, so find out exactly what's in them – and what makes them eco-friendly – before handing over your cash. 

Refillable products and those with plastic-free or recyclable packaging may be more sustainable in some ways, but check the ingredients to make sure they're not polluting in another way. Ideally, neither the product nor the packaging should harm the environment.

Our green brands guides give you more information on what some  of the more eco-friendly brands are doing to improve their sustainability.

Eco-friendly laundry alternatives

Soap nuts, which contain a natural surfactant called saponin, have been used for centuries to wash people and clothes. Also known as soap berries, they are the fruit of the Sapindus tree, and are entirely natural and biodegradable. 

Wash balls or laundry eggs, also known as ecoeggs and ecoballs, use natural mineral or plant-based pellets encased in a refillable plastic ball. Refillable dryer eggs are also available, which can reduce drying time and contain natural essential-oil fragrance sticks. 

A washing bag, such as the Guppyfriend, captures plastic microfibres from your washing and prevents them from entering the marine ecosystem. 

Instead of chemical fabric conditioners and synthetic fragrances, try naturally scented bags or sachets in drawers and wardrobes to keep clothes and linen smelling fresh. Many plant ingredients, including lavender, peppermint and eucalyptus, are also moth deterrents. 

Eco-friendly dishwashing alternatives

Washing-up soap bars are a sustainable alternative to washing-up liquid – they combine plastic-free packaging with biodegradable, non-polluting ingredients. They may take a little getting used to, but can still clean your dishes effectively.

Eco-friendly household cleaning alternatives

Try making your own natural cleaning products. You can bulk-buy ingredients such as citric acid (useful for descaling), bicarbonate of soda (which can neutralise acid, scrub shiny materials without scratching, deodorise and remove certain stains) and borax substitute (an all-purpose cleaner and scourer). 

These can be used for cleaning almost anything around the home. Read more on the science behind popular cleaning hacks.