Analysis of polyethylene microplastics in environmental samples, using a thermal decomposition method

Area of Science:

• Environmental Science
• Analytical Chemistry
• Polymer Science

Background:

• Microplastics, polymer particles <5mm, contaminate the environment from debris and industry.
• Accurate identification and quantification of microplastics are essential for environmental risk assessment.
• Existing methods may struggle with complex, non-homogenous environmental matrices.

Purpose of the Study:

• To develop and validate a method for identifying and quantifying microplastics in environmental samples.
• To generate reliable microplastic concentration data for environmental assessments.
• To demonstrate the method's capability using polyethylene (PE) as a model microplastic.

Main Methods:

• Thermal extraction using thermogravimetric analysis (TGA) coupled to a solid-phase adsorber.
• Analysis of adsorbers via thermal desorption gas chromatography-mass spectrometry (TDS-GC-MS).
• Utilized larger sample masses in TGA compared to Py-GC-MS for complex matrix analysis.

Main Results:

• The TGA-TDS-GC-MS method successfully identified and quantified microplastics.
• The technique is suitable for analyzing complex and non-homogenous environmental matrices.
• Polyethylene (PE) was effectively identified and quantified as a representative microplastic.

Conclusions:

• The developed TGA-TDS-GC-MS method provides a robust approach for microplastic analysis.
• This method enables accurate quantification of microplastics in diverse environmental samples.
• The technique facilitates reliable environmental risk assessment by providing essential concentration data.