Green brands: Smol

Is Smol more eco-friendly than other household cleaning brands? 93% of Which? members who had recently bought from the brand rated it as sustainable in our survey asking about sustainable brands.

Which? carried out a survey in February 2023 into member perceptions of sustainable brands. We asked members to rate how sustainable a brand was and then to give us their reasons why they thought that. We then took a further look at some of these brands to see whether the reality lives up to the perception.*

93% of respondents viewed Smol as a sustainable brand. The top reasons given were its recyclable or minimal packaging (67%), its lack of plastic packaging (62%), its natural/non-toxic ingredients (47%) and its low environmental impact products (47%).

We've looked in more detail at the sustainability initiatives and actions of cleaning brands Bio-D, Ecover, Method and Smol as these were the brands that members viewed as sustainable in our survey.

Why should we be worried about cleaning products' impact on the environment?

Chemicals often used in cleaning products can have an impact on water and aquatic organisms, soil health and indoor air pollution, as well as animal and human health.

Products that go down your drain should be treated at sewage treatment works. Most of the chemicals found in the product should biodegrade or be removed to prevent harmful amounts entering rivers and waterways. 

But this assumes that water companies are dealing with wastewater responsibly. Given that over recent years they’ve been found to be regularly discharging untreated sewage and wastewater into waterways, waste chemicals are increasingly ending up in our rivers and seas.

Studies have also found that these chemicals can be found in sewage sludge, which is sometimes used as fertiliser on farms. And the reality is that not everything fully breaks down.

Some of the potentially problematic chemicals that brands often declare themselves free from are:

• Parabens Used as a preservative and antimicrobial. They have been linked to endocrine disruption, but negative impacts of regular exposure at low levels have not been proven.
• Phosphates Were once widely used in laundry and dishwasher detergents, but their use has been severely limited to tiny amounts of no more than 0.3 grams per standard dose in the UK and the EU for some years now. Some brands have never used any phosphates.
• Phthalates Used for fragrance. Some have been linked to endocrine disruption and the risk of certain cancers, as well as developmental issues for humans and animals. Some phthalates have been banned in the EU. If you want to avoid phthalates, choosing fragrance-free is a good option.
• Triclosan Used as an antimicrobial or antibacterial. It can have negative impacts on aquatic environments, particularly algae. Studies have indicated that it is a potential endocrine disruptor in humans.

Smol: in summary

Who owns Smol?

Smol is a subscription service for cleaning products that was launched in 2018 by two former colleagues with the aims of making products that perform well but with lower chemical content. It is based in the UK and all its products are made either in the UK or the EU.

It sells laundry and dishwasher tablets as well as other cleaning products, packaged in cardboard and posted to your home.

Subscribers can tweak how often refills are sent based on how frequently they use each product.

We've tested Smol's dishwasher tablets in our lab to find out how they compare to other brands on cleaning power. It also sells laundry products, cleaning sprays and washing-up liquid.

Chemicals and ingredients in Smol

Smol doesn’t use parabens, phosphates, phthalates or triclosan.

Smol also states it doesn’t use methylisothiazolinone or isothiazolinones, which can be skin irritants. It avoids bleaching agents, though it does allow an optical brightener in its laundry detergent, which it says is readily biodegradable.

It is certified microplastic-free. Like many other mainstream brands its dishwasher tablets do contain a liquid polymer (acrylic copolymer), which the campaigning organisation The Plastic Soup Foundation says is poorly biodegradable.

Smol doesn’t focus on using plant-based/naturally derived ingredients, which means some of its chemicals come from petrochemical sources (ie they are derived from fossil fuels). This is common for household cleaning products, though some of the other companies that our members highlighted in our sustainable brands survey focus heavily on naturally derived ingredients. Smol says it uses smaller quantities of these chemicals in its products than leading brands.

It doesn’t test on animals and doesn’t sell in any markets that do test on animals. Its products are Leaping Bunny approved (a certification from Cruelty Free International).

All Smol's products are vegan.

Palm oil isn’t used as a direct ingredient in any Smol products but they may contain palm oil derivatives. These are RSPO (Roundtable on Sustainable Palm Oil) certified.

You may notice that some Smol products have a warning that they are dangerous to aquatic life. Smol says this is because it produces highly concentrated formulations containing little or no water to reduce transport emissions/weight, which would be dangerous if dropped directly into an aquatic habitat. Once its products are diluted in water, it says they are no longer classified as hazardous.

Smol’s packaging

You may be wondering about the film around Smol's laundry and dishwasher tabs. It protects the tabs when in storage, but dissolves in water when they're ready to be used. 

This film is used by many brands for this purpose. It's also found in things like contact lens lubricants. It is made of PVA (polyvinyl alcohol).

This is a biodegradable plastic that doesn’t release any microplastics as it breaks down. However, it's still a plastic and fossil-fuel derived, so it would be a stretch to call it an entirely eco-friendly material. There is also some dispute from organisations such as Plastic Oceans International about how quickly PVA biodegrades under less than perfect conditions.

Manufacturers must weigh up difficult choices around packaging. Using this wrapping means that each tab is protected in the box from any moisture getting in, without having to use other types of plastic packaging.

Some manufacturers use individual plastic wrapping around these tabs, which is hard to recycle. Others use a laminated outer box, which is also hard to recycle as it is a multi-layered material.

Smol says that an additional aspect to consider is that laundry capsules, including those with PVA film, create less friction in the wash than washing powder, which means that fewer microplastics are shed from synthetic clothing. So Smol regard its film-encased laundry capsules as the best available option for the product.

Aside from this plastic-based coating, Smol’s dishwasher and laundry tabs come in fully recyclable cardboard packaging that's 100% FSC (Forestry Stewardship Council) certified.

All plastic bottles used by Smol are made using 100% recycled plastic and are recyclable. They also have a free postal refill scheme.

Smol’s multipurpose spray bottle can be reused by adding water to a dissolvable tablet, so you only receive the bottle once, and subsequent deliveries are of tablets to use to refill it.

We've found in past research that solid tablets that you dissolve at home can be a much more efficient way of transporting detergents than those that come with water already mixed in, as it drastically reduces the weight and bulk of shipping the product. 

Find out more about buying refillable products.   

Other sustainability information

Of the household cleaning brands picked out by members as sustainable in our survey, Smol had the highest sustainability score, scoring higher than Bio-D, Ecover and Method.

Smol’s subscription model offers handy convenience for some customers, and its packaging is designed to be as minimal as possible. 

For its ingredient formulations, it avoids some of the more controversial chemicals, but it does use petroleum-derived chemicals that some other eco-brands avoid.

Other household cleaning brands rated highly by members in our survey were Bio-D (80%), Ecover (87%) and Method (77%).

*The brands that survey respondents could answer on were preselected based on a previous Which? survey carried out in November 2022 asking members to highlight brands they considered sustainable.

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