Environmental Fate and Ecotoxicological Impacts of Bioplastics: Degradation Pathways and Emerging Knowledge Gaps

Abstract

Plastic waste is one of the most concerning issues for the environment in the world. Many researchers are seeking sustainable solutions by replacing petroleum-based plastic with bio-based plastic. Bioplastic is synthesized from natural resources, and it can degrade in different ecosystems. Therefore, it could serve as alternative to combat the harmful impacts of conventional plastic. This review explores different bio-based polymers such as polylactic acid (PLA), polyhydroxyalkanoates (PHA), polybutylene succinate (PBS), starch blends (SB), and cellulose-based bioplastics (CB). These polymers can be used for many industrial applications, including agriculture, automobiles, textiles, packaging, and medical. To give insight into the procedure of bioplastic manufacture, various processes are analyzed in this review, including the solvent casting technique, extrusion techniques, injection molding, and 3D printing. The products of bioplastics such as micro-nano plastic, monomers, and oligomers released after degradation are critically analyzed and the toxicity of bioplastic on different ecosystems has been discussed. A research gap was also identified, as most toxicological studies of bioplastic do not include the LC₅₀/LD₅₀ threshold.