Release of microplastics from typical rainwater facilities during aging process

Area of Science:

• Environmental Science
• Materials Science
• Polymer Chemistry

Background:

• Urbanization increases reliance on plastic rainwater facilities.
• Aging and hydraulic scouring of these plastics can release microplastics into stormwater.
• This release presents a potential environmental pollution risk.

Purpose of the Study:

• To investigate microplastic release from typical plastic rainwater facilities.
• To understand the influence of UV aging and hydraulic scouring on microplastic release.
• To analyze the characteristics of released microplastics.

Main Methods:

• Simulated UV aging (15-45 days) and hydraulic scouring (72 hours) of plastic facilities.
• Surface analysis using Fourier transform infrared spectroscopy (FTIR), 2D-COS, and XPS.
• Quantification and particle size analysis of released microplastics.

Main Results:

• Aging increased surface roughness, cracks, and cavities, especially in storage modules.
• Formation of oxygen-containing functional groups correlated with microplastic release.
• Microplastic release varied by facility type (inspection well > storage module > pipe), ranging from 160-1905 items/g.
• Released microplastics (3-1363 μm) were predominantly 10-30 μm (50.10%).
• Release behavior depended on material composition and aging time.

Conclusions:

• Plastic rainwater facilities are a source of microplastic pollution in urban stormwater systems.
• Material degradation and surface chemistry are key factors controlling microplastic release.
• Further evaluation of microplastic pollution from these facilities is warranted.