Most pop-up sponges are made from cellulose, a plant-based fibre, which is derived from wood pulp or cotton. Cellulose is a natural polymer, known for its ability to absorb and retain water, making it an ideal material for sponges.
Compressed sponges are sold in a flat, thin shape, as that makes them lightweight and easy to store, and therefore popular for both household and industrial cleaning due to the convenience and environmental-friendliness.
They expand when exposed to water, but how does that happen exactly?
How do compressed sponges work?
Manufacturing: The sponge is first produced in a porous, expanded form. The air is trapped in the sponge fibres during this stage, which gives it its absorbent quality.
Compression: The sponge is heavily compressed, usually through a combination of heat and pressure that removes most of the air and water content.
Expansion: When you add water to the compressed sponge, the cellulose fibres absorb the liquid and swell. The cellulose fibres act like tiny capillaries, pulling the water into the material. The water molecules enter the spaces between the fibres, causing the sponge to expand rapidly. The sponge "pops up" and expands back to its original thickness and texture, becoming soft and absorbent.
What are the benefits of a compressed sponge?
Practicality: Since compressed sponges are flat when dry, they take up far less space than regular sponges, offering compact storage and transport. They are often used in kits or travel packs for this reason.
Sustainability: Most pop-up sponges are biodegradable and compostable, as they are made from natural materials. This makes them a sustainable alternative to synthetic sponges.
Reusability: Pop-up sponges can be washed and reused multiple times. You can freshen them up in the dishwasher or washing machine.
Versatility: Pop-up sponges are commonly used for washing dishes, cleaning countertops and general surface cleaning. Their softness makes them safe for delicate and non-stick surfaces. Smaller, more delicate versions of pop-up sponges are also used in cosmetics for applying or removing makeup, and in medical environments for cleaning wounds and applying antiseptics.
Durability: Pop-up sponges are designed to last longer than traditional foam or synthetic sponges. However, since they are made from natural materials, they will eventually break down, especially if they are used with harsh chemicals or abrasively scrubbed.
Plastic is everywhere. In our food packaging, water bottles, clothes, cosmetics, children’s toys and even the sponge sitting by the kitchen sink.
We already know what plastic waste does to the planet, but there’s another side to the story that’s much harder to see: the chemicals used to make plastic flexible, durable, colourful or water-resistant.
Some of these are known as endocrine-disrupting chemicals (EDCs). They can interfere with the hormones that help regulate everything, from growth and metabolism to fertility and reproduction. Research has linked exposure to some EDCs with reproductive, developmental and metabolic health problems, although scientists are still working to understand the effects of different chemicals, doses and combinations.
That's worrying, but this isn’t about panicking, emptying every cupboard or throwing away everything plastic overnight. It’s about knowing where exposure can happen and making a few sensible swaps when something needs replacing.
What are endocrine-disrupting chemicals?
Our hormones act as tiny chemical messengers, helping to control many of the body’s essential processes. Endocrine-disrupting chemicals can mimic, block or alter those signals.
Two of the best-known groups found in everyday plastics are:
Bisphenols, including BPA, which have been used to make hard plastics and epoxy resins, including the linings of some food and drink cans.
Phthalates, which are used to make plastics softer and more flexible and can also be found in some fragrances, cosmetics and household products.
The tricky bit is that these chemicals aren’t always firmly bound to the material. Over time, they can migrate out of packaging and other products, entering food, household dust or the air around us. We may then be exposed by eating, breathing or through skin contact.
And a “BPA-free” label doesn’t necessarily tell the whole story. BPA may be replaced with related chemicals such as BPS or BPF, which are also being studied for possible hormone-disrupting effects.
Where might you find them at home?
EDCs aren’t limited to one type of plastic or one room. Common sources include:
Plastic food containers and drinks bottles
The linings of some tins and cans
Cling film and other flexible food packaging
Takeaway cups and lids
Scented cosmetics, air fresheners and fragranced household products
PVC items and some synthetic furnishings
Thermal paper receipts
Household dust, where chemicals released from products can settle
This doesn’t mean every plastic product poses the same risk, or that occasional contact will make you ill. Exposure depends on the chemical, the amount, the way an item is used and how often you come into contact with it.
Does heat make a difference?
Yes. Heat, wear and prolonged contact can increase the movement of chemicals from some plastics into food or drink. That’s why one of the simplest changes is to avoid heating food in plastic, even if the container is labelled microwave-safe.
Seven easy ways to reduce your exposure
You don’t need a dramatic “plastic detox”. Start with the changes that are easiest and most relevant to your household.
1. Don’t heat food in plastic
Use glass, ceramic or another heat-safe non-plastic container in the microwave and avoid pouring boiling liquids into plastic unless the product is specifically designed for that use.
2. Store hot and fatty foods carefully
Heat can increase chemical migration, while fatty foods may absorb some plastic-associated chemicals more readily. Let food cool before putting it into plastic, or choose glass or stainless steel storage.
3. Choose loose or simply packaged food when practical
You don’t have to eliminate packaged food. But choosing loose fruit and veg, glass jars or less heavily processed options can reduce the amount of plastic your food touches.
4. Decant cupboard staples
Rice, pasta, oats and other dry goods can be transferred into glass jars or stainless steel containers, particularly if they’ll be stored for a long time. Reuse what you already own before buying a matching pantry worthy of social media.
5. Be fragrance-aware
Some phthalates are used in fragranced products and may be hidden under the general term “parfum” or “fragrance”. You don’t need to give up every scent you love, but choosing fragrance-free options for products you use frequently can reduce one source of exposure.
6. Say no to receipts you don’t need
Thermal paper may contain bisphenols. Choose a digital receipt when offered and wash your hands before preparing food after handling lots of receipts.
7. Keep dust under control
Regular vacuuming, damp dusting and opening windows can help remove dust where chemicals from household products may accumulate. Glamorous? No. Useful? Yes.
Don’t bin everything plastic today
Replacing perfectly usable belongings all at once creates more waste and more expense. A more realistic approach is to swap things gradually, prioritising plastics that come into contact with hot food and drink, items that are worn or damaged, and products you use every day.
Small changes repeated across a household can make a meaningful difference without turning life upside down.
Start with the sink.
One of the easiest places to begin is with the cleaning tools you replace regularly.
Many conventional sponges, scourers and cloths are made from plastic. As they wear down, they can shed microplastics into your washing-up water and eventually into our waterways and food chain.
At Seep, we make high-performing cleaning tools from natural and renewable materials, without the hidden plastic.
Explore Seep’s plastic-free cleaning tools
Sources:
The Times: The hidden chemicals in everyday plastic — and how to avoid them
World Health Organization: Endocrine-disrupting chemicals and child health
National Institute of Environmental Health Sciences: Endocrine disruptors
Endocrine Society: Plastics, EDCs and health
Every September, I convince myself that this will be the year I’m organised.
The uniforms will be ordered early, the shoes will fit, everyone will know where their calculator is. The cupboards will be stocked, the washing finished and I’ll return to the office refreshed, focused and completely on top of things.
It's never happened.
Back-to-school season isn’t one task. It’s about 47 small tasks that need doing at exactly the same time, usually while you’re still surrounded by half-unpacked suitcases and wondering how every plant in the house managed to die while you were away.
There are uniforms to check, which involves persuading the kids to try on clothes when neither of you can remember what fitted at the end of last term. I inevitably miss the secondhand uniform sale, find out something essential is out of stock and end up pre-ordering a jumper that may or may not arrive before Christmas.
Then come the shoes. An in-store experience that feels less like shopping and more like crowd control. Are they the right size? Is there enough growing room? Will they actually be worn, or declared deeply embarrassing within a week?
Next, we begin the annual hunt for the missing stationery. Calculators disappear, pencil cases mysteriously empty themselves, school bags that looked perfectly fine in July are suddenly deemed unusable. Old exercise books and folders are still lurking around the house, although nobody is quite sure which can be recycled, which must be kept and which apparently contain “really important stuff”.
Meanwhile, I’m attempting to restore some order at home.
The holiday washing has turned into its own mountain range. Summer items need putting away, the Tupperware cupboard has descended into complete anarchy, there are twelve lids and somehow none of them fit the three remaining containers.
I’ll do a food shop, forget what we already have and double-order half the kitchen. We’ll then have six cans of tomatoes but nothing anyone can actually take to school or work for lunch.
And then the WhatsApp messages begin. School groups, year groups, sports groups, clubs, classes, sign-up forms, payment reminders, dates for the diary. Dates that have changed since the last message. One notification leads to another until I’ve opened 14 conversations and can’t remember what I was originally trying to find.
This year I even nearly missed the netball sign-up, which would have been particularly embarrassing because I’m the organiser!
There’s also the health and life admin I’ve conveniently ignored all summer. Haircuts need booking, dentist appointments need arranging. Everything that felt like it could wait in July suddenly becomes urgent in September.
At the same time, I’m trying to switch my founder brain back on and catch up on work.
While I’ve been thinking about school timetables, work hasn’t exactly been quiet. On one particularly chaotic day, ten event enquiries landed in my inbox. There are meetings to organise, opportunities to assess and an investor-and-founder event in Leeds that I’ve mentally flagged but haven’t yet worked out how to fit into the diary.
Running a business and raising a family often means moving between completely different worlds within minutes. One moment I’m thinking about Seep’s next stage of growth, the next I’m trying to work out who has taken the only working black pen in the house.
My own routines have fallen away too. Exercise has slipped, meals have become more improvised. I keep telling myself I’ll get back into a rhythm once everything else is sorted, but perhaps that’s the trap - nothing is ever completely sorted. There will always be another form, another meeting, another load of washing or another cupboard that could do with a clear-out.
September has a funny talent for making us feel as though everyone else has returned from summer beautifully organised while we’re the only ones scrabbling around for a PE kit. I’m fairly sure that isn’t true.
So this year, I’m trying to resist the urge to fix everything in one heroic burst. I’m tackling one pile, one email and one sign-up form at a time. The dead plants may have to wait a little longer.
If you’re also limping rather than gliding into the new term, you’re in very good company!
Every July, millions of people around the world take part in Plastic Free July™, a global movement encouraging us all to cut back on plastic waste for a month.
It's been going for 15 years, and the movement has achieved so much. We also think that perhaps it's time to evolve it. From an absolute pledge to remove all plastic items from your lifestyle (virtually impossible in our world) for one month, to reducing plastic every day of the year. Starting simply, room by room, looking at your routines and the products you buy.
So here are some tips from the Seep team.
What is Plastic Free July™?
Plastic Free July™ is a global movement that helps millions of people reduce plastic waste through simple, everyday choices.
It began in 2011 with just 40 people in Western Australia who wanted to challenge themselves to refuse single-use plastics for one month. Today, it has grown into the world's largest waste reduction campaign, with more than 174 million participants across 190 countries.
The aim isn't perfection. It's about becoming more aware of the plastic we use every day and discovering that many of those items have better, longer-lasting alternatives.
Every reusable bottle, refill, or compostable sponge helps reduce the demand for disposable plastic and brings us one step closer to cleaner streets, healthier oceans and less pollution in our homes and bodies.
How can you take part?
One of the best things about Plastic Free July™ is that anyone can take part, regardless of their lifestyle. Rather than trying to change everything overnight, focus on one swap each week. It's scientifically proven that small, realistic habits are far more likely to stick than an all-or-nothing approach.
Here are a few easy ideas:
Swap cling film for reusable silicone food covers or beeswax wraps.
Choose glass food storage instead of plastic containers where possible.
Carry a reusable coffee cup or water bottle.
Buy loose fruit and vegetables when you can.
Choose refillable household products like deodorant, cleaning sprays, and laundry detergents. There are some fabulous alternatives out there.
Choose natural fibres when buying clothing and avoid polyester and acrylic.
Switch to plastic-free cleaning essentials made from natural materials.
By the end of the month, you'll have made several simple changes that could last for years!
Does Plastic Free July™ really make a difference?
Absolutely. What started with just 40 participants has become one of the biggest environmental movements in the world.
Since 2011:
More than 174 million people have taken part.
The campaign has reached 190 countries.
Participants have helped avoid an estimated 15 million tonnes of plastic waste.
86% of people say the changes they made during Plastic Free July™ became permanent habits.
That's the real power of the movement. It's not just about one month of action - it's about creating everyday habits that reduce plastic waste long after July has finished.
Easy plastic-free swaps for your cleaning routine
The cleaning cupboard is one of the easiest places to reduce plastic. Many conventional sponges, scourers and cloths are made from plastic and shed microplastics every time they're used. Those fibres are washed down the sink and can eventually find their way into our rivers, oceans, and even our bodies.
Switching to plastic-free cleaning products is one of the simplest changes you can make. At Seep, we've designed everyday cleaning essentials using natural, renewable materials that work brilliantly without relying on plastic. From compostable sponge scourers to plastic-free cloths, these alternatives are just as effective and easy to use as the traditional products you're replacing.
Every small swap adds up
Plastic Free July™ isn't about being perfect. It's about progress.
One reusable bottle won't solve plastic pollution. One compostable sponge won't clean up the oceans. But when millions of people each make one small change, those choices quickly add up.
So this July, choose one thing to swap. Next week, swap another. Before long, you'll have built a home that's a little lighter on plastic and taken a step towards a cleaner future.
Looking for an easy place to start?
Explore Seep's range of plastic-free cleaning essentials and discover how everyday swaps can make a lasting effect on your home and the planet.