Upon examining the biodegradability of various fabric types in the ocean for the first time, researchers at the Scripps Institution of Oceanography, UC San Diego found that natural and cellulose-based fabrics from wood degraded within a month. In contrast, Polylactic Acid (PLA), a touted biodegradable plastic, and oil-based sections of fabric blends didn’t show any degradation signs after over a year underwater.
Biodegradable and compostable PLA, a bio-based plastic made from renewable resources like corn starch or sugar cane, is often hailed as a solution to the plastic problem and was therefore chosen for the study. 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, 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.
These textile samples were placed in containers in the sea and observed every seven days. High-resolution scans and spectroscopy were used for in-depth examination. The procedure continued until 231 days at the ocean’s surface and 196 days at the seabed. The samples were then transferred to Scripps Oceanography’s Experimental Aquarium, where natural and cellulose-based textiles disintegrated within 30-35 days, but oil-based and bio-based materials showed no sign of degradation even after 428 days.
The study also highlighted that the oil-based portion of fabric blends, often marketed as a sustainable alternative, remained intact despite the natural fibres degrading. Independently, the same fabric types were tested in a bioreactor, simulating a marine environment, where cellulose-based materials completely biodegraded within 28 days, but oil-based and bio-based fibres showed no degradation.