Bioplastics in the Sea: Rapid In-Vitro Evaluation of Degradability and Persistence at Natural Temperatures

The progressive substitution of petroleum-based polymers, such as polyethylene, polyvinylchloride, or polyethylene terephtalate, by so-called bioplastics facilitated the development and production many new materials. continuously refined properties bioplastic compounds their blends enable various applications. With growing utilization products, these materials are increasingly discarded into environment. Although labeled biodegradable, there is limited information about degradability under environmental conditions. We tested enzymatic five with rapid pH-Stat titration assay at environmentally relevant seawater temperatures between 5 30°C pH 8.2. These plastics, issued from European Horizon 2020 Project ´Bioplastics Europe´, based on polylactic acid (PLA), polybutylene succinate (PBS), poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV). Suspensions microparticles (< 200 µm) were incubated each three hydrolytic enzymes, protease, lipase, esterase. A PLA-based compound blended adipate terephthalate (PBAT) showed highest hydrolysis rate 30 nmol·min -1 when lipase 30°C. All other low rates less than 10 . Below 20°C, almost ceased. Plate clearing assays same enzymes 37°C 8, respectively, largely confirmed results assays. Our findings indicate that a potential degradation most least one enzymes. Nonetheless, conditions low, which indicates only marginal in marine