A fast and simple PFAS extraction method utilizing HR-CS-GFMAS for soil samples.

Area of Science:

• Environmental Chemistry
• Analytical Chemistry

Background:

• Per- and polyfluorinated alkyl substances (PFASs) are persistent environmental contaminants.
• Accurate quantification of PFASs in soil is crucial for environmental monitoring and risk assessment.
• Traditional methods often involve solid phase extraction (SPE), which can introduce bias.

Purpose of the Study:

• To develop an optimized, fast, and simple extraction method for PFAS determination in soils.
• To eliminate the bias associated with SPE in extractable organically bound fluorine (EOF) analysis.
• To provide a more accurate, economic, and ecological method for PFAS analysis.

Main Methods:

• Development of a liquid-solid extraction using acidified methanol.
• Implementation of a SPE-free approach for soil sample preparation.
• Utilized high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) for EOF determination.

Main Results:

• The optimized SPE-free method achieved >80% extraction of EOF in four steps.
• Comparison revealed SPE significantly underestimated EOF concentrations by up to 94%.
• The method's procedural limit of quantification (LOQ) was 10.30 μg/kg, suitable for environmental samples.

Conclusions:

• The developed SPE-free extraction method is accurate, efficient, and cost-effective.
• Bypassing SPE provides a more reliable measurement of EOF in soils.
• This method is valuable for future PFAS monitoring and regulatory decisions.