Larger plastics in the environment would continually degrade into microplastics as a result of physical, chemical and microbial effects, resulting in an annual increase in the amount of microplastics.Thus, it is essential to understand the degradation processes of plastic particles to increase our understanding of the source of microplastics, predict the fate of microplastics in the environment, and evaluate the potential environmental hazards to organisms.Knowing the degradation process of plastics in different environments is critical for calculating their residence times in different environments and providing a basis for evaluating the status of plastic pollution in these environments.