Microfibres vs Microplastic: What’s the Difference and Why is this important? 

When people think of microplastic pollution, they usually imagine tiny, colourful fragments in confetti form from broken bottles, damaged fishing nets, or packaging that’s been pushed into the sea from winds.

The truth is, a significant portion of microplastic pollution that enters our sea comes when washing our clothes in a washing machine.  

But How?

• Our clothes are made from textiles 
• Textiles are made from threads
• Threads are made from fibres
• Fibers that are 5mm or less are called microfibres

When we wash our clothes in a washing machine, the water, detergent, softener and  fast-paced spinning of the drum helps the microfibres shed from our textiles. Once the microfibres are released into dirty grey water, they travel through the drainage system, bypass the treatment plant and flow straight into the sea.

But here’s the crucial point:

Not all microfibres are microplastics.

So why does understanding the difference matter?

Because treating all plastics the same way is ineffective, costly, and fails to stop pollution at its source. Microfibres can be recycled with a laundry machine filters, keeping materials in the system, not the sea.

Microfibres vs Microplastics

“Microfibre” describes shape and size of a tiny textile thread
“Microplastic” describes a small plastic fragment 

Some microfibres are plastic-based. Others are not.

Synthetic Microfibres (Microplastics)

Synthetic microfibres are made from petroleum-derived polymers, including:

• Polyester
• Nylon
• Acrylic
• Polypropylene
• Spandex
• Aramids
• Modacrylic
• Polyethylene

When these fibres shed from clothing or textiles, they are classified as microplastics. Because they are petroleum-based, they fall squarely under the category of microplastic pollution.

Synthetic microfibres are durable, lightweight, and resistant to degradation—qualities that make them useful in clothing. But in nature, this same durability becomes a problem. They can persist for long periods and even carry pollutants, acting as long-term contaminants in the environment.

Semi-Synthetic Microfibres

Also known as bio-based manmade fibres, examples include;

• Viscose
• Modal
• Lyocell
• Cupro
• Bamboo Rayon
• Acetate
• Triacetate

These are made from natural polymers (usually cellulose or proteins) that are chemically processed and extruded into very fine filaments (microfibres).

While these aren’t plastics, these engineered fibres still shed from clothing, enter waterways, and can carry chemical treatments with them.

Natural Microfibres (non sythetic) Plant Based

• Cotton
• Linen
• Hemp
• Jute

Natural fibres generally biodegrade faster than synthetic ones. However, that does not make them impact-free. During the manufacturing process, they are often dyed, treated and finished with a range of chemicals, which remain attached when microfibres shed.

Natural Microfibres (non synthetic) Animal based

• Wool
• Silk
• Cashmere

Even natural fibres shed during washing. When tiny enough, they become microfibres. While they biodegrade faster than synthetics, they can still carry dyes and chemicals into our waterways.

The Hidden Chemistry of Clothing

Every microfibre, regardless of origin, carries chemical additives.

These can include:

• Dyes and pigments
• Finishing agents such as formaldehyde-based resins
• Flame retardant
• Water and stain repellents
• Antimicrobial agents
• Plasticisers and stabilisers
• Bleaching and processing chemicals
  

Some of these substances are tightly regulated due to concerns about toxicity, persistence or bioaccumulation (Pollutants piling up inside living things).

So when microfibres enter waterways, they are not simply inert strands. They can act as chemical carriers.

Riding the Plastisphere

Once microfibres enter waterways, they quickly develop a biofilm, a thin microbial coating that attracts bacteria, algae, and fungi. Scientists refer to this as the “plastisphere”, a miniature ecosystem living on plastic surfaces.

In fact, microfibres are particularly good at hosting microbes because:

• Their long, thin structure provides ample attachment points
• Their high surface-area-to-volume ratio makes them ideal for colonisation
• They remain suspended in water longer than heavier plastic fragments

Rather than behaving like passive debris, microfibres can act as mobile rafts for microbes, similar to barnacles clinging to driftwood in the ocean.

Plastic Rafts for Pathogens

Microfibres don’t just float—they carry tiny passengers. They can transport bacteria downstream from wastewater discharge points and shield microbes from UV light and predators, helping them survive longer than free-floating cells.

Pathogens like Vibrio, E. coli, and Pseudomonas have been found on microplastics, and even viruses can attach to fibres or hide in biofilms. Early research suggests that microfibres may help microbes persist in waterways, making these tiny threads more than just pollution—they are mobile ecosystems with real impacts on our seas.

Impacts from Rivers to Reefs

Microfibres move easily from rivers to the ocean. Wastewater treatment plants can release them alongside microbes, while sedimentation patterns determine where they settle, often in riverbeds, estuaries, and coastal zones.

Once in the sea, microfibres can drift long distances, forming increasingly complex biofilm communities.

This can have several ecological impacts, including:

• Damage to phytoplankton, which produce over half of the planet’s oxygen
• Disruption of zooplankton, the foundation of the marine food chain
• Contamination of seafood, particularly filter feeders such as mussels
• Transmission of coral diseases

Large-scale disease outbreaks directly linked to microfibres are still being studied. However, researchers are increasingly examining their role in transporting antibiotic resistance genes and concentrating pathogens in shellfish-growing waters.

Because synthetic microfibres persist for longer, they can act as long-term transport platforms for microbes.

Why is this Important?

Microfibre pollution is not just about visible plastic fragments. It is about:

• Chemistry
• Microbiology
• Water systems
• Food chains
• Ecosystem stability

And it begins in the most ordinary place: our washing machines.

Once fibres enter our water, they do not simply disappear.

They interact.
They travel.
They persist.

And the systems they touch are far larger than the clothes we wear.

Turning Understanding into Action

Understanding the problem is one thing. Stopping it is another.

If microfibres start in our washing machines, that’s where intervention makes the most sense.

The Indi™ Home Microfibre Filter retrofits onto domestic washing machines, capturing microfibres before they enter the drainage system. Working quietly in the background, it intercepts synthetic, semi-synthetic, and natural fibres at source, preventing them from travelling downstream and becoming a larger environmental problem.

For commercial and industrial laundries, Indikon™ Industrial Filters offer a scalable solution to microfibre pollution. Designed for high-flow environments like hospitality, healthcare, and textile facilities, they integrate into existing laundry systems and capture microfibres before they reach drains or the sea.

By preventing microfibre release at scale, they reduce environmental harm while helping organisations meet sustainability goals, generate data for reporting, and, where water is a key material topic, support responsible water stewardship.

The Indi™ Home Microfibre Filter and the Indikon™ Industrial Filters are engineered to be fully closed loop and adopt the circular economy principles as once the microfibres are captured they are returned to Cleaner Seas Group for recycling. 

There is no longer a need to put microplastic pollution in home refuse, landfill or be incinerated. 

Microplastic  pollution may be complex. The solution does not have to be.

Stop microfibre pollution at source. Dispose of microfibres responsibly. Protect  our seas.