EASUMMIT: The Value of Ion Chromatography to Environmental Analysis

Significance of the Topic

Ion chromatography coupled with mass spectrometry is a powerful approach for detecting trace anionic species in environmental and drinking water matrices. This technique addresses critical challenges in water quality monitoring, regulatory compliance and public health by enabling accurate, low-level quantitation of pollutants such as perchlorate, haloacetic acids and polar pesticides.

Objectives and Study Overview

This work presents a series of applications illustrating the value of suppressed ion chromatography (IC) with MS and tandem MS detection. Three main case studies are explored:

• Perchlorate analysis following EPA Method 332.0
• Haloacetic acids determination via EPA Method 557
• Polar pesticide screening including glyphosate, AMPA and glufosinate

Methodology and Instrumentation Used

The analytical workflows combine high-resolution separation with sensitive mass detection:

• Chromatography platforms: Thermo Fisher ICS-5000+, ICS-4000, Integrion, Aquion with RFIC technology, eluent generators and electrolytic suppressors
• Columns and eluents: KOH gradient on IonPac AS24/AG24 columns at controlled temperatures
• Mass spectrometers: TSQ Endura, TSQ Quantis and TSQ Altis for MS/MS, Q Exactive Focus Orbitrap for high-resolution MS
• Sample introduction: direct injection (100 µL) with makeup flow of organic solvent, internal standards (e.g. 18O-perchlorate) for quantitation robustness

Main Results and Discussion

Perchlorate measurements achieved detection limits of 5–50 ppt with accurate isotope ratio confirmation and robustness in high total dissolved solids matrices. Haloacetic acids analysis demonstrated sub-ppb quantitation for nine HAA species plus bromate and dalapon without derivatization, exceeding regulatory criteria. Glyphosate and related polar pesticides were quantified at ng/L levels, with linear calibration across various matrices (0.01–1 µg/L) and reproducibility (RSD <5%).

Benefits and Practical Applications of the Method

This IC-MS/MS approach offers:

• High sensitivity and selectivity, reducing matrix interferences
• Elimination of laborious derivatization and extraction steps
• Multi-analyte capability under unified chromatographic conditions
• Confirmation of analytes by mass and isotope ratios
• Compliance with stringent EPA and EU regulations

Future Trends and Potential Applications

Ongoing developments include expanded target lists for emerging contaminants, integration of non-targeted high-resolution screening, automation of sample preparation and potential deployment in real-time water quality monitoring. The convergence of RFIC with advanced MS promises broader applications in food, pharma, and clinical testing.

Conclusion

Ion chromatography coupled to MS/MS and high-resolution MS platforms delivers a robust, sensitive and streamlined solution for environmental contaminant analysis. These methods meet or exceed regulatory demands while enhancing laboratory throughput and data confidence.