Interception of urban surface source waste plastics by typical permeable paving materials

Currently, research on preventing plastic pollution in aquatic environments mainly focuses on source control and end-of-pipe salvage. However, studies targeting the interruption of migration pathways remain limited. Urban surface runoff generated by rainfall is a significant pathway for plastic pollutants entering water environments. The optimal strategy to interrupt this pathway involves widely implementing permeable paving materials to eliminate surface runoff. This study evaluated the effectiveness of two novel permeable paving materials—permeable brick and permeable asphalt—in intercepting plastic pollutants by simulating precipitation processes. The results indicate that both permeable brick and permeable asphalt effectively eliminate urban surface runoff, thereby preventing urban-derived plastic pollutants from entering aquatic environments. Both materials intercept over 90% of plastic pollutants by mass, though permeable bricks exhibit a higher interception efficiency than permeable asphalt. Although complete removal of plastic pollutants is not achievable, the majority of plastic debris is captured and retained on the pavement surface. Provided that timely street cleaning is conducted, plastic pollutants accumulated on pavements can be collected through the municipal waste disposal system, preventing further environmental pollution.