Application and Validation of the First Automatic Pretreatment Unit for Aquatic Microplastics.

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Microplastic contamination poses a significant threat to aquatic ecosystems globally.
• Current microplastic analysis methods are often labor-intensive, operator-dependent, and lack standardization.
• Automated solutions are needed to improve the efficiency and reliability of microplastic detection.

Purpose of the Study:

• To apply and validate the Shimadzu MAP-100, the first automated unit for microplastic pretreatment.
• To assess the unit's performance in standardizing microplastic analysis and improving recovery rates.
• To evaluate the effectiveness of the automated system for both controlled and real-world environmental samples.

Main Methods:

• The MAP-100 unit was tested using river water spiked with aged microplastics and field-collected seawater.
• Fourier transform infrared (FT-IR) spectroscopy was used to analyze spectral integrity and polymer identification post-pretreatment.
• Performance was evaluated based on recovery rates, organic matter removal, and mineral particle elimination.

Main Results:

• Automatic pretreatment preserved FT-IR spectral integrity, ensuring reliable polymer identification.
• The MAP-100 demonstrated effective removal of soluble organic matter and complete elimination of mineral particles.
• Higher recovery rates for aged microplastics (95.6%) were achieved compared to manual methods (92.7%), especially for small and dense particles.
• Foam microplastic recovery was reduced, indicating a need for design modification in the overflow system.

Conclusions:

• The MAP-100 offers a standardized, automated workflow for microplastic pretreatment, reducing labor and processing time.
• The unit enhances reproducibility and operational safety in microplastic monitoring.
• While effective, minor design adjustments are needed to optimize recovery for all microplastic types, particularly foam.