Bio-based fibers may pose risks to soil ecosystems – Study

By Faridat Salifu

Bio-based fibers may pose serious environmental risks, especially to important soil species, according to a recent study.

Bio-based fibres have been widely promoted as environmentally friendly substitutes for conventional plastics.

According to the recent study published in Environmental Science and Technology, however, these fibers could potentially harm earthworms, a vital species for soil health worldwide, even more than conventional plastic fibers.

The study, led by researchers from the University of Plymouth and the University of Bath as part of the BIO-PLASTIC-RISK project, tested the impacts of common bio-based fibers, such as viscose and lyocell, on earthworms.

Unlike traditional plastic fibers, which are known to contribute to pollution but typically remain stable, bio-based fibers, according to the study, tend to break down over time, releasing microfibers into the soil through routine activities such as laundry, sewage sludge applications, and everyday wear of textiles.

The study said while bio-based materials have been seen as a promising solution to the plastic pollution crisis, this research underscores the potential dangers they may pose to ecosystems.

In the study’s experiments, earthworms exposed to high concentrations of viscose and lyocell experienced strikingly high mortality rates, with 80% dying when exposed to viscose compared to 30% mortality in earthworms exposed to conventional polyester.

Even at lower concentrations, which mirror real-world conditions, these bio-based fibers affected earthworm growth, reproduction, and behavior, suggesting long-term ecological impacts.

Dr. Winnie Courtene-Jones, lead author of the study, emphasized the importance of understanding the full environmental impact of bio-based materials before promoting them as widespread alternatives to plastic.

“Our findings show that bio-based fibers can have a range of adverse effects on earthworms—organisms essential to soil health,” Courtene-Jones explained.

She stressed that while the world is rightfully eager to reduce plastic waste, testing new materials in realistic settings is crucial to prevent unintended ecological consequences.

The study comes at a critical time, with world leaders set to discuss a potential Global Plastics Treaty in Busan, South Korea, in the coming weeks.

Professor Richard Thompson, a senior author of the study and a respected voice on marine pollution, will join policymakers and scientists at the summit.

He cautions against the wholesale adoption of alternatives without comprehensive research. “While it’s crucial to reduce our reliance on plastics, we need to ensure that alternatives are tested thoroughly to avoid replacing one environmental problem with another,” Thompson stated.

As the world grapples with plastic pollution, the findings serve as a reminder that “green” materials must be rigorously evaluated to prevent potential risks to ecosystems.

The study advocates for a balanced approach: while reducing plastic production and increasing recycling are key strategies, each innovation should undergo robust testing to safeguard the environment’s complex and interdependent systems