Researchers at the Scripps Institution of Oceanography, UC San Diego discovered that natural and cellulose-based textiles from wood disintegrated within a month after being tested in the water for the first time. Polylactic Acid (PLA), a lauded biodegradable plastic, and oil-based parts of fabric blends, on the other hand, showed no evidence of disintegration after more than a year underwater.
PLA, a bio-based plastic manufactured from renewable resources such as maize starch or sugar cane, is frequently praised as a solution to the plastic problem and was thus chosen for the study.
According to the study titled ‘Not so biodegradable: Polylactic acid and cellulose/plastic blend textiles lack fast biodegradation in marine waters’ published in the PLOS One journal, ten different types of commonly used fabrics in the textile industry were tested, including natural cellulose, wood-based cellulose, bio-based plastic (PLA), oil-based plastic, and mixed fabric blends.
These textile samples were placed in marine containers and monitored every seven days. An in-depth investigation was carried out using high-resolution scans and spectroscopy. The technique was carried out for 231 days on the ocean’s surface and 196 days on the bottom. The samples were subsequently taken to Scripps Oceanography’s Experimental Aquarium, where natural and cellulose-based textiles dissolved in 30-35 days, whereas oil-based and bio-based fabrics exhibited no signs of deterioration even after 428 days.
The study also found that the oil-based component of fabric blends, which is frequently advertised as a sustainable option, remained intact despite natural fibre degradation. In a bioreactor replicating a marine environment, the same fabric types were tested independently, and cellulose-based materials biodegraded after 28 days, whereas oil-based and bio-based fibres exhibited no deterioration. According to the article, authored by Lauren Fimbres Wood and published on the UC San Diego website, the study calls for more research into how these materials behave in natural environments, as bio-based PLA plastic and oil-based materials, such as polyethene terephthalate and polypropylene, are a significant source of pollution.
“This study shows the need for standardising tests to see if materials promoted as compostable or biodegradable biodegrade in a natural environment,” said Sarah-Jeanne Royer, who conducted the research as a postdoctoral fellow in the Dimitri Deheyn group at Scripps Oceanography. What biodegrades in an industrial context may not biodegrade in the natural environment, where it may end up as marine and environmental toxins.
“Because the natural, cellulose-based materials disintegrate in about a month, we would exchange for a new sample once the old one disintegrated.” The natural, cellulose-based samples were reproduced five times, while the other materials were left alone for almost a year.”
Royer, Francesco Greco, Michaela Kogler, and Dimitri D Deheyn performed the study, which was supported by the Biomimicry for Emerging Science and Technology Initiative and the Walter Munk Foundation for the Oceans.
