A modified QuEChERS method for extracting different classes of emerging contaminants in soil

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Soil Science

Background:

• Emerging contaminants (ECs) in soil present significant health and toxicity risks.
• Existing methods for simultaneously extracting diverse EC classes from soil are limited.
• A need exists for efficient, multi-contaminant soil extraction techniques.

Purpose of the Study:

• To develop a rapid and robust pretreatment method for simultaneous extraction of 50 ECs from soil.
• To validate the QuEChERS-based method for accuracy, precision, and matrix effects.
• To establish method detection limits for various EC classes.

Main Methods:

• Utilized Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) technology for soil pretreatment.
• Employed acetonitrile and methanol with magnesium sulfate and sodium chloride for extraction.
• Purified extracts using C18 sorbent.
• Analyzed per- and polyfluoroalkyl substances (PFAS), organophosphate esters (OPEs), and diesters (di-OPEs).

Main Results:

• Achieved recoveries between 70%-120% and relative standard deviations (RSD) below 20% for most ECs.
• Observed matrix effects ranging from 73%-123% for PFAS and di-OPEs, and 30%-93% for OPEs.
• Compensated for matrix effects using internal standards, with exceptions for tris (2-ethylhexyl) phosphate (TEHP) and 4:2 fluorotelomer sulfonate (4:2 FTS).
• Determined method detection limits for PFAS (0.01-0.21 ng/g), OPEs (0.01-3.96 ng/g), and di-OPEs (0.03-0.16 ng/g).

Conclusions:

• The developed QuEChERS method enables high-throughput, simultaneous extraction of diverse ECs from soil.
• The method demonstrates acceptable accuracy and precision for environmental monitoring.
• This approach can be integrated with non-target screening for comprehensive soil contaminant analysis.