Bio-based fibers can pose a greater threat to the environment than plastics

A recent study has suggested that bio-based fibers, which are often marketed as environmentally friendly replacements for plastics, may pose greater ecological threats than previously thought. The research, carried out by the University of Plymouth and the University of Bath as part of the £2.6 million BIO-PLASTIC-RISK project, shows that these fibres, used in everyday items such as clothing and wet wipes, can contain microfibres that damage ecosystems, especially through laundry effluent, sewage sludge and abrasion-induced fiber shedding.

Comparison of bio-based fibers with conventional plastics

In a detailed analysis, scientists compared the impact of conventional polyester with two common bio-based fibers, viscose and lyocell, on earthworms – species essential for soil health. The findings showed that bio-based materials may be significantly more dangerous. In laboratory tests, up to 80 percent of earthworms exposed to viscose fibers died, compared to 30 percent mortality among those exposed to polyester. When exposed to lyocell, 60 percent of the earthworms did not survive. At lower environmentally relevant exposure levels, viscose was associated with lower reproductive rates, while lyocell led to reduced growth and altered burrowing behavior.

Importance of rigorous testing for new materials

Dr. Winnie Courtene-Jones, a lecturer in marine pollution at Bangor University and lead author of the study, pointed out the crucial need for more extensive testing. She noted that although bio-based and biodegradable fibers are produced in large volumes – more than 320,000 tons in 2022 – insufficient data exists on their impact on the environment. “Our research underlines the importance of evidence-based approaches before introducing new materials that aim to replace conventional plastics,” said Dr. Courtene-Jones, emphasizing that ecological impacts, especially on soil health, must be included in evaluations of bio-based plastics. products.

Implications for the future of plastic alternatives

This study, which builds on previous research linking biodegradable tea bags to increased earthworm mortality, comes ahead of key discussions on plastic pollution at the upcoming UN conference in Busan, South Korea. Professor Richard Thompson, head of the International Marine Litter Research Unit at the University of Plymouth, emphasized the need for an evidence-based strategy. He noted: “Reducing plastic pollution is essential, but this research shows that replacement materials must undergo rigorous environmental testing to avoid unintended consequences.”