Organic fibers could pose a bigger environmental threat than plastics, new study suggests

A recent study suggests that organic fibers, often marketed as eco-friendly substitutes for plastics, may pose greater ecological threats than previously thought. Led by the University of Plymouth and the University of Bath as part of the £2.6 million BIO-PLASTIC-RISK project, the research reveals that these fibres, used in everyday items such as clothing and wet wipes, can release microfibers that harm ecosystems, in particular. by laundry wastewater, sewage sludge and wear-induced fiber loss.

Comparison of organic fibers with conventional plastics

In a detailed analysis, scientists compared the impact of conventional polyester with two common biological fibers, viscose and lyocell, on earthworms, species vital to soil health. THE results showed that materials of biological origin could be much more dangerous. In laboratory tests, up to 80% of earthworms exposed to viscose fibers died, compared to 30% mortality in those exposed to polyester. When exposed to lyocell, 60 percent of earthworms did not survive. At lower, environmentally relevant exposure levels, viscose was associated with lower reproductive rates, while lyocell resulted in reduced growth and altered burrowing behaviors.

Importance of Rigorous Testing for New Materials

Dr Winnie Courtene-Jones, senior lecturer in marine pollution at Bangor University and lead author of the study, highlighted the crucial need for more comprehensive testing. She noted that although bio-based and biodegradable fibers are produced in large volumes – more than 320,000 tonnes in 2022 – there is insufficient data on their environmental impacts. “Our study highlights the importance of evidence-based approaches before deploying new materials aimed at replacing conventional plastics,” said Dr Courtene-Jones, noting that ecological impacts, particularly on soil health , must be taken into account in the evaluations of materials of biological origin. products.

Implications for the future of plastic alternatives

The 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 United Nations conference in Busan, South Korea . Professor Richard Thompson, director of the International Marine Litter Research Unit at the University of Plymouth, stressed the need for an evidence-based strategy. He noted: “Reducing plastic pollution is essential, but this research shows that substitute materials must undergo rigorous environmental testing to avoid unintended consequences. »