A Basis for Standardization: Optimizing Sampling Methods and Quantities for Accurate Microplastic Assessment in a...

Area of Science:

• Marine Biology
• Environmental Science
• Ecotoxicology

Background:

• Microplastics (MPs) pollution is a pervasive global issue, threatening marine ecosystems and organisms.
• Existing marine MP monitoring suffers from inconsistent sampling methods and quantities, hindering accurate impact assessments.
• Standardized methodologies are crucial for reliable environmental monitoring and understanding MP distribution.

Purpose of the Study:

• To investigate the influence of different sampling methods and quantities on microplastic survey results in marine environments.
• To determine optimal sample mass for beach sediments and effective sampling parameters for seawater microplastic detection.
• To enhance the accuracy and reliability of marine microplastic monitoring protocols.

Main Methods:

• Examined the impact of sample mass on MP detection in supratidal, intertidal, and subtidal beach sediments (sandy and muddy).
• Evaluated seawater MP collection using trawl, water collector, and pump sampling methods, varying quantities, filter apertures, and sampling depths.
• Analyzed MP abundance, polymer composition, and size distribution across different sampling parameters and marine zones.

Main Results:

• A minimum sample mass of 30 g is recommended for detecting MPs in beach sediments.
• Optimal seawater sampling parameters include trawl durations of at least 10 minutes and water collector volumes of at least 10 L.
• Filtration pore size showed no significant effect on total MP abundance but influenced detected MP size ranges; variations in polymer composition and size were observed across water layers.

Conclusions:

• Standardized sampling strategies, including adequate sample mass and volume, are essential for accurate marine microplastic monitoring.
• Comprehensive sampling across different marine zones (supratidal, intertidal, subtidal) is necessary for a complete MP abundance assessment.
• This research provides critical insights for refining marine microplastic monitoring protocols, improving data comparability, and informing environmental management strategies.