Biodegradable nappies: are they actually better for the environment?

But do these 'biodegradable' nappies decompose more quickly on the UK's rubbish tips? Are they really completely biodegradable? How does it all work, and what do you need to know? Let’s find out…

Everything you need to know about biodegradable nappies

What does ‘biodegradable’ mean?

The dictionary definition of biodegradable says it means a product or substance is “capable of being decomposed by bacteria or other living organisms and thereby avoiding pollution”.

What are biodegradable nappies made of?

There’s no one formula; it seems to differ from brand to brand. But it's fair to say that most appear to contain more environmentally-friendly or more natural fibres and fabrics than you’d expect in a traditional disposable.

Here’s a quick overview of a few key brands:

• Mama Bamboo. Shortlisted in the MadeForMums Awards 2018, these nappies are made of bamboo fibres and chlorine-free wood pulp. As a result, the product "can achieve 80% decomposition over time".

• Beaming Baby. Formed with a "biodegradable water-resistant outer sheet, made with natural cotton and cornstarch paper". The GM-free absorbent layer is "fortified with 100% natural cornstarch" and the nappies "contain only clean plastics" . They are “77% biodegradable, including packaging”.

• Eco by Naty. Made of 60% renewable materials, such as “wood pulp to help with absorption, a back sheet and distribution centre based on bio-based materials, as well as cellulose in the nappy”.

• Bambo Nature UK. The fluff in these nappies is biodegradable, says the manufacturer.

Naty and Bambo Nature UK also use super-absorbent polymers, which is important for the absorption function of a nappy.

These polymers – "sodium polyacrylate salts together with surface cross linking agents" in Naty’s case – allow the nappies to be less bulky and use less material but still leave your baby with a dry bottom.

Some of these polymers are biodegradable, and some are not. Typically, they are considered very safe. They are, as it stands, kind of unavoidable if you’re buying disposables.

So, are biodegradable nappies 100% biodegradable?

No. There is no disposable nappy currently on the market that is 100% biodegradable.

As you can see from the details on some of the big brands mentioned above, most biodegradable brands only claim to be made of 60 % to 80% biodegradable material.

Do biodegradable nappies biodegrade in a landfill?

No, they don't. Even the 60% to 80% bits that are actually biodegradable. Confused? We're not surprised!

It turns out that the biodegradable material in the nappies only biodegrades if the nappies are composted – in a particular way. And if your average rubbish truck just dumps the nappies in a landfill site, composting just isn't going to happen.

"Disposables of any sort won't biodegrade in landfill sites, as landfill sites are managed to keep decomposition as low as possible due to the gases and liquid that leaches out," says Wendy Richards, best known as cloth/reusable nappy seller and advice site The Nappy Lady.

Indeed, methane, carbon dioxide and small amounts of other gases rise into the atmosphere when ‘organic waste’ start to decompose. So landfills are designed to minimise this effect.

So, while these nappies are absolutely 60% to 80% biodegradable, if they're put on a landfill site, they aren’t able to reach their full biodegrading potential…

So how long does it take biodegradable nappies to biodegrade at the moment?

The reality is: it could take several lifetimes for the biodegradable bits of a nappy to actually decompose on their own, or in a landfill site.

In fact, according to our sister site Science Focus, synthetic biodegradable materials actually take hundreds of years to fully decompose. Plastics, generally, take 3 to 6 months.

The Nappy Lady brought our attention to a BBC documentary, The Secret Life of Landfills, which showed a disposable nappy from the 1980s still totally in tact.

“[They] dug up a disposable nappy from the 1980s and it was completely recognisable as a nappy, was all still complete and could have been put on a baby (besides being dirty obviously).

“They also dug up a newspaper from the same landfill site from the 1980s and read it just as you would a new newspaper from today.

“If newspapers aren't biodegrading in nearly 40 years, a disposable nappy made of many components isn't going to biodegrade.”

Interestingly, Mama Bamboo says, on its website, that it takes 3 months for 60% of their product to biodegrade.

"In ideal hot compost conditions the nappies biodegrade 60% in less than 3 months," a representative told us over email. "This would be much slower in landfill due to lack of oxygen and microbes."

(They did, however, add that they were looking into possible landfill alternatives - and were talking to one UK council about offering a hot composting service.)

Beaming Baby claims their nappies take 4 years to biodegrade. We’ve reached out to them to see if that’s true in a landfill environment, and we’ll let you know if we hear back.

Naty, to be fair, is pretty open about how their nappies can biodegrade, explaining on their website that 51% of the nappy will biodegrade only in an industrial compost.

Can you compost biodegradable nappies at home?

Composting is the process of making an organic matter into a soil conditioner, decomposing natural fabrics or waste and turning in to something else, something usable.

It seems composting is the only way to ensure any of your disposable nappy actually biodegrades. It’s probably the closest thing you could ever get to recycling used disposable nappies.

In theory, these are the ways you’d do it:

• you learn to do it at home and use the soil in your garden
• take your used nappies to an industrial composting facility
• use a nappy disposal service to take the used nappies to the facility for you.

Unfortunately, none of these options are actually very do-able here in the UK. Firstly, doing it at home is not recommended for several reasons:

• you’d need SO many nappies for it work
• it wouldn’t work for pooey nappies; just wet ones
• you’d have to separate the bits of the nappy you can biodegrade from the bits you can't – which would be incredibly difficult, time-consuming and messy
• it could pose a possible health risk. (As we’ve mentioned, anything decomposing does produce a number of gases, like methane.)

RecycleNow also says NOT to put disposable nappies of any sort in your brown compost bin.

As for letting the pros do it, there is, at present, no industrial facility you can drive to in the UK or one that offers a pick-up service – as far as we can tell.

The Nappy Lady confirms this: “No, there isn’t. There was a company in Wales that was trying to start it but they went out of business.

“Recycling should always the last resort as it requires even more energy and resources to recycle,” says Wendy. "Reduce and reuse should be the steps before recycle.”

Could we have a nappy compost service in the UK?

Just because there isn't currently a used nappy pick-up service in the UK, doesn't mean there couldn't be one day.

Across the world, they do exist, and seem to do the job. We've heard of them existing in New Zealand and other parts of the world. However, it seems they're all pretty small-scale, right now.

We spoke to Mark Arishenkoff, co-founder of Soiled Diaper, a used-nappy pick-up service in Calgary, Canada, and asked him to explain how it works in some detail:

"We offer weekly, bi-weekly (fortnightly) and monthly collections – for private residents," Mark says. (On a subscription basis. They do try to work with councils on a municipal-level, too.)

"We go [to homes] and collect the nappies and we bring it back to our facility, shred them up to organic material and once it's all shredded up, it goes into the composting unit and it takes 10 to 12 days from start to finish to compost the nappies.

"At the end, any of the inorganic bits that don’t compost, we screen those out, and we send them for further processing. Any of the clean plastics can go to be pelletised, any of the dirty plastics can be recycled… and all we’re left with is the reusable organic compost.

"In Canada, this is something super new and super-innovative, so they don’t have any regulations based on compost made from nappies, so we’re not allowed to sell it. It takes about a year of testing before we get a rating back, and then we can do it.

"This is being done in New Zealand and many other parts of the world right now and their compost is already approved for things like mine reclamation sites, or roadside rehabilitation, or turf builder – anything that’s not food-related.

"Our end goal is to get approval to have the compost used to be able to combat soil erosion for farms."

As a long-term solution to the nappies-in-landfills problem, does this work for the environment? Is it the best alternative? Mark reckons so...

"The amount of energy our composting machine uses is very similar to a commercial, walk-in cooler [in a restaurant kitchen]. So, it’s really not very much energy.

"There are no emissions from it. Everything that comes out of it is double-filtered, through a carbon-bio filter and a condensate filter as well. People often ask if there’s any toxic sludge or whatever… but the condensate is actually recycled back into the composting material, to be used for the moisture content that’s required, so there’s no leaching [of gases].

"There’s no other machine on the market that we’re aware of that produces no leaching. We’re not sending harmful materials back into the environment.

"On average, nappies in a landfill will help to produce I think something like 8 million tonnes of carbon and methane (per year). Doing it this way, we end up producing something like 800kg per year. So it’s exponentially fewer emissions going into the environment."

Still, nothing is perfect: "We obviously need to use collection trucks. We do our best to do research and find the most fuel-efficient vehicles that we can. If its possible or available, we use alternate fuels, so its producing less emissions, too."

We're not waste management experts or scientists but a system like this on a larger-scale has to be food for thought, right?

We have tried to speak to waste management experts WRAP (Waste & Resources Action Programme, who are behind RecycleNow) on the topic, but they told us they were unable to comment.

We've also reached out to a number of other experts and professionals, so we'll let you know if we hear back.

If they don’t fully decompose (or take AGES to decompose), are there still benefits to using biodegradable nappies?

We don't want this piece to seem negative. After all, it's not really the nappy companies' fault that many of these biodegradable materials aren’t actually disposed of in a way that allows them to biodegrade.

Their products *technically* could biodegrade in the right environment. However, that's probably not what you have in mind when you buy them.

"People are often taken in," Mark says. "They see that a nappy is labelled as compostable or biodegradable and they think, 'Oh good, when it goes to the landfill, it’s not gonna be there as long'. When, in fact, it’s gonna be there just as long because there’s no movement, there’s no air, nothing’s gonna help it biodegrade."

Still, you can expect the makers of these nappies to have taken the environment into consideration in other areas, which is very important.

Often, they’ll have thought about how ethically it’s been made, the type of and amount of packaging, and the use of chemicals, plastics, etc.

We mentioned some of the benefits above, such as being free of chlorine, or using more ‘natural’, sustainable materials like wood pulp.These are big pluses.

Finally, many eco-friendly and biodegradable brands also take into consideration sensitive skin and other concerns, so it’s worth looking into for that reason, too.

Are reusable cloth nappies better for the environment than disposable nappies?

Like with most things in life, there are pros and cons to both – and it's up to you which route you go down.

Reusable cloth nappies aren't going to run into the landfill problem because they don’t end up in landfills; you keep washing and reusing them.

But therein lies the challenge. They DO require regular washing and drying– on a high heat – which bumps up your overall energy usage. If not managed properly, this can impact the environment, creating more carbon emissions.

("We recommend storing used nappies in a nappy bucket so that they can be washed in one big load rather than smaller, more frequent washes in order to save on water, time and money," says reusable nappy company Bambino Mio's Head of Product, Carly Baillie.

"We recommend a 40°C wash for reusable nappies, along with the recommended amount of non-biological washing powder and 15ml of nappy cleanser to get the best out of them. Line/air drying away from direct heat are the most environmentally-friendly options, but they can also be tumble dried on a low/cold setting if needed.)

To be fair to regular ol’ disposables, The Telegraph reports that they HAVE shrunk in their bulkiness quite a bit over the years.

A 2008 review of a study by the Environment Agency acknowledges this – and says it does make a difference to the environmental impact of them all sitting in the landfill.

That said, they do still end up in a landfill. So, that's not particularly brilliant for the environment, either. Sigh.

Does that mean regular disposable nappies are bad?

Don’t feel guilty about using disposables. Or reusables. You have to use some kind of nappy. Or things really would be chaos ?

Whatever you decide is what’s right for you, and you can still make sure you’re doing your bit for the environment by being conscious and recycling in other areas of your home life.

We’d also say that we’ve seen a few parents use a combo of reusables and disposables, and we reckon this is something to consider if you’re feeling a bit troubled by it.

Finally, if a nappy brand calls itself ‘eco-friendly’, does it contain biodegradable materials?

Eco-friendly is a term that basically means it’s ecologically or environmentally-friendly in some way. This could refer to so many things, and not necessarily how it decomposes.

For example, it could have used less chemicals than other brands. Perhaps the packaging could be plastic-free. Maybe the product has been made in a fair, ethical way.

Make sure your nappy brand of choice is what you want it to be – by reading the FAQs on their official website, reading reviews, and doing your homework before buying.

Have your say

Do you use biodegradable nappies, and if so, are you happy with your purchase? Perhaps you’ve chosen an eco-friendly brand for a variety of reasons?

We’d love to hear from you either way, so get in touch in the comments below!

Images: Getty Images

Read more:

• Best nappies for toddlers - tried and tested by mums
• 6 of the best eco-friendly nappy changing products
• Best reusable nappies for newborns, babies and toddlers