Unlocking accurate microplastic data: Advanced pump systems for diverse aquatic environments

Microplastics (MiPs) pose a significant environmental threat due to their persistence and potential toxicity to biota that interact with or ingest them. Accurate assessment of MiP concentrations in aquatic systems is critical for understanding their distribution and impacts. This study develops the MiPCS Pump (Microplastic Collector System), an innovative pump-based sampling system integrating 80 μm mesh plankton nets. The system was tested against traditional net-based methods (manta and Apstein nets) in the Red River Delta and Cat Ba Archipelago, Vietnam. This innovative design features a suction basket excluding large particles (>5 mm), a mixing chamber and 5-way splitter for uniform distribution, and precise flow control (via flow metering) to five phytoplankton nets, ensuring accurate and simultaneous multi-sample collection. This advanced system provided more consistent and precise results, sampling a broader spectrum of MiP sizes, and enabling sampling across a variety of water depths and environmental conditions. Quantitatively, MiPCS Pump yielded significantly higher MiP concentrations (2.95-7.80 mg m^-3 and 16.25-114.58 particles m^-3) compared to the net methods (1.59-3.27 mg m^-3 and 0.78-26.62 particles m^-3). Although nets are effective for larger surface MiPs (mesoplastics) there is a lack of understanding of MiP catchability in nets, whereas the MiPCS Pump offers precise volume measurement, adaptability to various depths, and captures a broader size range, making it a more comprehensive method for assessing MiP pollution. This MiPCS Pump system is crucial for ensuring accurate and comparable data for global MiP monitoring and the development of effective plastic waste management policies.