Microplastics monitoring in different environments: separation, physicochemical characterization, and quantification

Area of Science:

• Environmental Science
• Environmental Chemistry
• Polymer Science

Background:

• Microplastics (MPs) contaminate diverse global environments, including water and soil.
• Environmental factors like wind and water facilitate the redistribution of MPs, necessitating widespread monitoring.
• Understanding MP contamination requires investigating multiple environmental compartments simultaneously.

Purpose of the Study:

• To systematically investigate microplastic contamination in a wastewater treatment plant (WWTP), surrounding water bodies, and soils near plastic factories.
• To characterize the physical and chemical properties of microplastics found in these environments.
• To establish a foundational dataset for future microplastic research in understudied regions.

Main Methods:

• Physical examination, microscopy, and Fourier transform infrared (FTIR) spectroscopy were used to characterize MPs.
• Analysis included MP shape, size, color, concentration, and functional groups.
• Samples were collected from WWTP influent and effluent, the Yellow River, and soils adjacent to plastic production facilities.

Main Results:

• Wastewater treatment plants removed over 99% of microplastics, with influent concentrations significantly higher than effluent and river water.
• Fragments and fibers were the dominant MP types in water samples; transparent fragments predominated in soil.
• Soil near plastic factories exhibited high MP abundances (2.1-2.7 × 10^5 items/ha) with polymer types including PP, PB, PE, and PET.

Conclusions:

• Wastewater treatment plants are critical in mitigating microplastic pollution in aquatic environments.
• Plastic production facilities are significant sources of soil microplastic contamination.
• This study provides crucial data on microplastic pollution in multiple environmental matrices in a previously understudied region.