Biodegradable plastics: Green hope or greenwashing?

The universality of plastic has an inescapable responsibility for the large-scale production of plastic wastes. Fossil-based plastics, which account for the majority of the market, are dazzling, and the global environmental pollution caused by them is also becoming more and more complicated. In addition to controlling the total amount at the source, people have also actively sought some emerging materials to replace existing conventional plastics so that they can be handled better and easier at the end. Biodegradable plastics (BPs) can theoretically shorten the life cycle of plastics and reduce environmental stress. However, in the natural environment, many factors are uncontrollable, and whether BPs can alleviate white pollution needs further certification. Due to the wide and complex physical and chemical conditions encountered in natural ecosystems, great care must be taken in trying to define this term. The current standards and test methods are insufficient to predict the biodegradability of BPs in the natural environment. Additionally, the existing standards and test methods for biodegradability of water environment do not involve toxicity tests, nor do they consider the potentially adverse ecological effects of BPs or micro BPs particles that may be produced by crushing. Therefore, this article mainly discusses whether BPs are green hope or greenwashing: 1) Degradability in the environment; 2) Impact of existing waste management; and 3) Recycling Impact of resources and impact on global carbon sequestration. Successfully solving these knowledge gaps is the key requirement of the new standard for the production of BPs.