Can plastic-eating funghi help clean up nappy waste?

Before Leila Green became a mother of triplets three years ago, she envisaged she'd be the kind of parent who would use reusable nappies.

"But as soon as my babies arrived, I realised I just couldn't – I was flat out looking after the three of them so I went for the easy option."

"I'd buy disposables and in the early days we'd get through 25 a day," continues Green, who lives in Broadstairs in Kent and runs an online community focused on motherhood issue.

"I think the reality is that mums would like an eco option but they are so busy and it would have to be priced appropriately."

Globally, it's estimated that 300,000 disposable nappies are sent to landfill or incinerated every minute, leading to environmental issues as many contain plastics and synthetic materials and can take hundreds of years to decompose.

While there's sustainable alternatives such as washable nappies, the effort and cost limits how widely they're used.

Over the years many start-ups have marketed greener alternatives to disposable nappies. Can the latest make an impression?

Texas-based company Hiro Technologies has created unbleached disposable diapers that comes with a packet of fungi which is added to the used diaper when it's ready to be thrown away.

The fungi are able to break down and digest the diaper over time, says co-founder Miki Agrawa, who started the brand after being shocked by how many nappies her son was going through.

So how quickly does it work? Agrawa says it's hard to be specific.

"We cannot give a timeline because all conditions are different and the fungi currently works in some conditions better than others," says Agrawa.

"All we can say that it's exponentially faster than without the fungi in the best conditions, and still better than nothing in the worst conditions."

The diapers cost $136 (£100) for a month's supply, though there is a subscription price of $199.

That's significantly more than regular disposables, which are estimated to cost around $70 a month.

Is the price out of range for most parents?

"The price is less expensive than luxury diapers," replies Agrawa. "I think it's a great deal for the diaper that is best for baby and their planet they will grow up in."

She adds that demand is growing fast.

Price tags aside, Sonali Jagadev, senior research analyst at Euromonitor, says progress in creating a more innovative and sustainable nappy remains slow and uneven due to several factors including high production costs and supply chain constraints.

"Bio-based polymers, bamboo fibres and organic cotton all come with higher raw material and processing costs than traditional plastics, while the supply chains for these sustainable inputs are still immature, making prices volatile and challenging for mass market brands," she says.

Jagadev says smaller players face bigger hurdles. "Rising inflation, higher raw material costs and the need for heavy marketing investment can make it difficult for them to survive, even when their sustainability credentials are strong."

Lack of composting infrastructure is another challenge. "Most biodegradable nappies still end up in landfill because industrial composting facilities are limited or unavailable in many regions," says Jagadev.

And, of course, there are consumer priorities. "Parents continue to prioritise performance, hygiene and convenience over sustainability, meaning brands take a risk if greener solutions compromise any of these core expectations."

In Belgium, Woosh is another start-up hoping to clear those hurdles.

Woosh says its nappies are easier to recycle as they are not made of multiple materials.

Instead, says Alby Roseveare co-founder and chief technology officer, Woosh has focused on using one specific kind of plastic.

"If you use different plastics, it's extremely difficult to separate [when recycling]."

The company is also working with daycare centres to deliver nappies and collect the used ones.

These are then processed in their own recycling station, with some materials reused.

"We wanted to focus on putting the right materials in so we can get the right materials out and unless you take responsibility to take your own waste back, no one is incentivised to do this," says Roseveare.

"Big brands are incentivised to optimise costs, but in most cases there's no incentive for brands to pay much attention to the recyclability of the nappy."

Woosh currently works with over 1,400 daycare centres across Belgium and says over 30,000 children wear Woosh nappies every day.

They are piloting working with retailers and are in the process of rolling out its circular model to parents at home.

Nappy and wipes brand, Pura is also focused on recycling.

With support from the Welsh government, it recycles 60 million nappies in Wales annually.

Dirty nappies are collected at curbside and processed at the NappiCycle plant in South Wales.

It uses a process called friction washing to break down the used nappies into a mixed material can be used in all sorts of applications from road surfacing to creating benches.

Back in Ghent, Roseveare says he's hoping such joined-up approaches can lead to fewer nappies in the landfill.

"We have ambitions to create as much impact as possible and are seeing where else we can expand to in Europe."