A high-throughput analytical method for complex contaminant mixtures in biosolids

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Agronomy

Background:

• Biosolids, rich in nutrients, enhance soil properties and plant growth for agricultural sustainability.
• Land application of biosolids offers resource recovery benefits over landfilling or incineration.
• Biosolids contain trace-level chemicals, necessitating robust analytical methods for risk assessment.

Purpose of the Study:

• To develop and validate a simplified, rapid, and robust analytical method for quantifying 44 high-priority organic contaminants in biosolids.
• To address the limitations of existing methods in analyzing diverse chemical mixtures within the complex biosolids matrix.
• To enable comprehensive risk management associated with biosolids land application.

Main Methods:

• Development and validation of a novel extraction and cleanup protocol for biosolids.
• Utilization of Ultra-Performance Liquid Chromatography coupled with tandem Mass Spectrometry (UPLC-MS2).
• Application of internal standards and standard addition method for accurate residue quantification due to matrix effects.

Main Results:

• The developed method successfully validated extraction and cleanup for 42 out of 44 targeted compounds.
• UPLC-MS2 parameters were validated for all 44 target organic contaminants.
• 86% of targeted contaminants were detected with 100% frequency, with concentrations ranging from 0.036 to 10,226 μg/kg dw.
• First-time detection and quantification of 6PPD-q, lidocaine, and 11 other chemicals in biosolids using a single method.

Conclusions:

• A simplified, rapid, and robust analytical method has been successfully developed and validated for a broad range of organic contaminants in biosolids.
• The method overcomes matrix effects through the combined use of internal standards and standard addition.
• This validated method provides crucial data for managing risks associated with biosolids land application and can be expanded for other matrices and analytes.