Microplastic fibers, also known as microfibers, are the most abundant microplastic forms found in the environment. Microfibers are released in massive numbers from textile garments during home laundering via sewage effluents and/or sludge. This review presents and discusses the importance of synthetic textile-based microfibers as a source of microplastics. Studies focused on their release during laundering were reviewed, and factors affecting microfiber release from textiles and the putative role of wastewater treatment plants (WWTPs) as a pathway of their release in the environment were examined and discussed. Moreover, potential adverse effects of microfibers on marine and aquatic biota and human health were briefly reviewed. Studies show that thousands of microfibers are released from textile garments during laundering. Different factors, such as fabric type and detergent, impact the release of microfibers. However, a relatively smaller number of available studies and often conflicting findings among studies make it harder to establish definitive trends related to important factors contributing to the release of microfibers. Even though current WWTPs are highly effective in capturing microfibers, due to the presence of a massive number of microfibers in the influent, up to billions of fibers per day are released through effluent into the environment. There is a need to establish standardized protocols and procedures that can allow meaningful comparisons among studies to be performed.

As the most abundant natural polymer, cellulose is a prime candidate for the preparation of both sustainable and economically viable polymeric products hitherto predominantly produced from oil-based synthetic polymers. However, the utilization of cellulose to its full potential is constrained by its recalcitrance to chemical processing. Both fundamental and applied aspects of cellulose dissolution remain active areas of research and include mechanistic studies on solvent–cellulose interactions, the development of novel solvents and/or solvent systems, the optimization of dissolution conditions, and the preparation of various cellulose-based materials. In this review, we build on existing knowledge on cellulose dissolution, including the structural characteristics of the polymer that are important for dissolution (molecular weight, crystallinity, and effect of hydrophobic interactions), and evaluate widely used non-derivatizing solvents (sodium hydroxide (NaOH)-based systems, N,N-dimethylacetamide (DMAc)/lithium chloride (LiCl), N-methylmorpholine-N-oxide (NMMO), and ionic liquids). We also cover the subsequent regeneration of cellulose solutions from these solvents into various architectures (fibers, films, membranes, beads, aerogels, and hydrogels) and review uses of these materials in specific applications, such as biomedical, sorption, and energy uses.