Beyond Synthetic Microplastics: The New Frontier

Discussions around sustainable fashion and textile pollution often focus on synthetic fibers like polyester and nylon, which shed microplastics into the environment. However, recent research has highlighted another category of fibers that behave similarly: anthropogenic cellulose microfibers.

These are natural fibers, such as cotton and bamboo rayon, that have undergone extensive chemical treatments, altering their biodegradability and impact on ecosystems. While marketed as "natural," these materials can be far from their original state by the time they reach consumers.

How Do Anthropogenic Cellulose Microfibers Form?

Natural fibers, in their raw form, are biodegradable and break down in the environment. However, through conventional textile processing, they are often treated with a range of synthetic chemicals to improve durability, colorfastness, and other performance factors.

These treatments fundamentally change the fibers' properties, making them more persistent in the environment and introducing chemical residues that can affect human and ecological health.

When washed, these chemically altered fibers behave much like synthetic microplastics, breaking down into microscopic fragments that enter waterways. Unlike untreated natural fibers, which degrade quickly, these microfibers remain in the environment, carrying traces of the chemicals used in their processing.

Comparing Conventional Cotton and Bamboo Rayon Processing

To understand how anthropogenic cellulose microfibers form, it is important to examine the full production process of two commonly used fibers: conventional cotton and bamboo rayon. Both undergo extensive chemical treatments, but the processes differ significantly.

Organic Certifications and Their Limits

Organic textile certifications, such as GOTS (Global Organic Textile Standard) and OEKO-TEX, play a significant role in reducing the presence of synthetic chemicals in textiles. These standards regulate pesticide use, restrict hazardous chemical treatments, and enforce fair labor practices.

However, while organic certifications eliminate many harmful substances, they still permit the use of synthetic dyes, often labeled as "low-impact dyes."

The Role of Dyes in Microfiber Pollution

Dyes play a critical role in how fibers interact with the environment. Synthetic dyes, including low-impact dyes, require chemical binders and fixatives that alter the fiber's structure and longevity. This can lead to increased microfiber shedding and environmental persistence.

An alternative approach is the use of plant-based dyes, such as those utilized by AIZOME. These natural dyes do not contain petrochemical derivatives or synthetic fixatives, eliminating concerns about chemical pollution.

In fact, emerging research suggests that plant-dyed textiles may even offer functional benefits beyond aesthetics. AIZOME's plant-dyed textiles have demonstrated antibacterial properties, as evidenced by laboratory testing.

By using medicinal plant dyes, textile manufacturers can reduce the environmental burden of dyeing while potentially enhancing the well-being of the wearer.

Unlike synthetic dyes, which introduce chemicals into the environment through laundering, plant-based dyes decompose naturally without leaving behind toxic residues, offering a true alternative to the current system of mass textile dyeing.

Why Does This Matter?

Studies have shown that microfibers are now ubiquitous in our oceans and waterways. As the infographic below illustrates, research by Suaria et al. (2020) found that a shocking 44% of particles floating in our oceans are actually anthropogenic cellulose fibers—chemically treated "natural" materials like rayon, viscose, and conventionally processed cotton.

These anthropogenic cellulose fibers—made from trees and plants but heavily processed with toxic chemicals—actually exceed the proportion of plastic microfibers (35%) found in marine samples. Despite marketing claims of being "eco-friendly," these fibers don't readily biodegrade due to their chemical treatments. Yet while regulations increasingly target synthetic microplastics, anthropogenic cellulose microfibers remain largely overlooked in environmental policies and consumer awareness.

What Can Be Done?

• 🔍 Material Transparency: Advocating for greater disclosure of textile treatments can help consumers and businesses make informed choices about fiber selection.
• 🌿 Sustainable Alternatives: Choosing untreated or minimally processed natural fibers reduces the release of persistent microfibers into the environment.
• 🔄 Responsible Manufacturing: Innovations in plant-based dyeing and mechanical finishing (rather than chemical treatments) offer ways to maintain fabric performance without synthetic additives.

Moving Forward

As the conversation around textile pollution evolves, expanding the focus beyond synthetic microplastics to include chemically altered natural fibers is a critical step.

Understanding the chemical processes that create anthropogenic cellulose microfibers allows us to push for more sustainable practices, reducing environmental impact while maintaining textile quality and performance.

By choosing textiles with minimal chemical processing and plant-based dyes, consumers can help reduce the environmental footprint of their home textiles while creating healthier living environments.