Aquatic Biodegradability of Cotton, Polyester and Rayon Yarns

摘要

The aerobic biodegradation of the most common textile yarns were studied under the action of microbes naturally found in the environment, such as lake and seawater. The interactions between microfibers and the microbiome in the test mediums was assessed combining aerobic biodegradation tests and molecular biology techniques such as next-generation sequencing to understand the fate of textile fibers in the environment. Under the action of both microbial communities, cotton, and rayon, yarns were completely disintegrated and highly assimilated by the microorganisms into each system. In general the biodegradation percentage achieved with the lake water sample as inoculum was significantly higher than with the seawater sample as inoculum. Nevertheless, the order of biodegradation potential was the same in both experiments Microcrystalline cellulose (MCC) > Cotton > Rayon > Polyester/Cotton > Polyester. For cotton and rayon yarns, around 70% of biodegradation was achieved for both materials in lake water whereas in seawater only 50% was reached based on the consumption of oxygen versus the theoretical oxygen demand. Polyester did not degrade under the conditions studied. The biodegradation of the blend was between the degradation extents of the cotton and polyester alone. Distinct bacterial genus related with the assimilation of complex carbohydrates were identified in the test mediums of MCC. cotton, and rayon samples.