From bulk to bits: understanding the degradation dynamics from plastics to microplastics, geographical influences and analytical approaches.

The popularity of plastics in major application sectors is creating an increasing burden of pollutants in the environment in the forms of plastics and microplastics. More than 6 billion tons of plastics now reside in the environment, which is now an available source of secondary microplastics. Research focused on the degradation of plastics/microplastics dealing with different environmental conditions and their change in properties. Despite being a serious pollutant, sufficient resources are still missing for the transformation of secondary microplastics from large plastics and how to detect the level of degradation before this transition. This article's brief review provides insight into the current scenario of plastics, disposed waste plastics, management system, and their limitations. In addition, a detailed explanation of the transition of plastics to microplastics, their mechanism, and the effect of different geographical conditions on degradation is also demonstrated. Moreover, the available analytical techniques to understand the degradation index of different polymers are also described in addition to the future perspectives for research in this area. This review could provide valuable insight into the formation of microplastics from waste plastics and their mechanisms in addition to a comprehensive knowledge of the quantification of the degradation.