Quick and efficient microplastic isolation from fatty fish tissues by surfactant-enhanced alkaline digestion

Area of Science:

• Environmental Science
• Analytical Chemistry
• Marine Biology

Background:

• Microplastic contamination in fish poses a significant environmental and health concern.
• Accurate identification and quantification of microplastics require efficient tissue digestion methods.
• Existing protocols are often time-consuming, hindering large-scale monitoring.

Purpose of the Study:

• To develop a swift and efficient tissue digestion protocol for microplastic analysis in fish.
• To achieve high microplastic recovery rates for relevant particle sizes.
• To enable filtration of large sample masses with small pore sizes.

Main Methods:

• A novel digestion protocol combining surfactants (Tween®-20, Triton™ X-100) with potassium hydroxide (KOH) and pH neutralization.
• Pre-treatment of fish tissues to remove bones.
• Application to various fish tissues including fillets, liver, head kidney, and oil samples.

Main Results:

• Successful recovery of microplastics (PA-66, PE, PET, PP, PS, PVC) down to 60-80 µm.
• Protocol effective for fish tissues with varying fat content (mackerel, salmon, plaice, cod).
• Achieved filtration of 100 g samples with a 10 µm pore size within 16-24 hours.

Conclusions:

• A rapid and efficient digestion protocol for microplastic analysis in fish tissues has been developed.
• The method significantly reduces processing time compared to existing protocols.
• Enables comprehensive monitoring of microplastic contamination in diverse fish matrices.