AGILENT WATER ANALYSIS SOLUTIONS - Application Notebook

Importance of the Topic

The analysis of environmental contaminants in water is critical for public health, regulatory compliance, and ecosystem protection. Advanced analytical methods provide the sensitivity, selectivity, and throughput needed to detect trace levels of pollutants—including polycyclic aromatic hydrocarbons (PAHs), organophosphate pesticides, polybrominated diphenyl ethers (PBDEs), and trace elements—in drinking water, wastewater, and natural water bodies.

Objectives and Overview of the Studies

These application notes describe four analytical workflows developed by Agilent and collaborating laboratories to meet or exceed regulatory methods and to optimize laboratory productivity:

• Determination of 24 PAHs in drinking water by automated SPE and fast HPLC with fluorescence and diode-array detection.
• Implementation of U.S. EPA Method 538 for 11 organic contaminants in drinking water by direct aqueous injection UHPLC–MS/MS.
• Simultaneous GC/MS/MS quantitation of PAHs and PBDEs in wastewater effluents using a single liquid–liquid extraction.
• Ultra-fast ICP-OES analysis of 32 trace elements in water conforming to EPA 200.7, leveraging next-generation sample introduction to double throughput.

Methodology and Used Instrumentation

• PAHs in Drinking Water: 800 mL water samples spiked with BaP-d12, automated SPE on Bond Elut Plexa, elution and concentration, HPLC on Agilent Pursuit PAH column (100×4.6 mm, 3 μm), fluorescence detection with time-programmed excitation/emission, and UV detection for non-fluorescent PAHs.
• EPA Method 538: Direct injection of 40 mL preserved water, addition of five deuterated internal standards, UHPLC on Agilent ZORBAX Eclipse Plus C18 (2.1×50 mm, 1.8 μm), 10 min gradient, Agilent 6460 Triple Quadrupole LC/MS with Jet Stream, two MRM transitions per analyte.
• PAHs and PBDEs in Wastewater: Liquid–liquid extraction with aqueous ammonia and hexane, overnight rolling, concentration, injection on Agilent 7890 GC with multimode inlet solvent vent, Agilent J&W HP-5 column (30 m×0.25 mm, 0.25 μm), Agilent 7000B GC/MS/MS in MRM mode for 14 analytes plus internal standards.
• Trace Elements by ICP-OES: Sample preparation with matrix matched calibration, internal standard of CsNO₃/Sc, analysis on Agilent 720 axial ICP-OES, SeaSpray nebulizer, and Agilent Switching Valve System (SVS 2) to preload sample loops and maintain constant flow for <70 s per sample.

Main Results and Discussion

• SPE–HPLC/FLD–DAD method achieved separation of 24 PAHs in 28 min, limits of quantification down to 0.01 μg/L, recoveries 45–95%, R² > 0.99.
• UHPLC–MS/MS direct injection shortened EPA Method 538 run to 10 min, detection limits 1–500 ng/L, linearity R² ≥ 0.9999, confirmatory MRM transition, no SPE required.
• GC/MS/MS method resolved 14 PAHs and PBDEs in <20 min with single extraction, reporting limits <3 ng/L, U.K. water quality program compliant, recoveries 92–107%.
• ICP-OES with SVS 2 halved analysis time from 2.5 min to 68 s per sample, maintained stability <2% drift over 6 h, MDLs below regulatory requirements, full EPA 200.7 conformance.

Benefits and Practical Applications

• High throughput reduces per-sample cost and increases laboratory capacity.
• Automation and direct injection eliminate labor-intensive sample preparation steps.
• Enhanced sensitivity and selectivity meet stringent regulatory limits for water quality.
• Flexibility to analyze diverse contaminant classes on unified platforms.

Future Trends and Opportunities

Expected advancements include integration of high-resolution MS for non-target screening, further miniaturization of sample preparation, cloud-based data management for real-time compliance tracking, and combined speciation analyses to characterize chemical forms and bioavailability of trace contaminants.

Conclusion

These Agilent-based methods demonstrate robust, sensitive, and high-throughput solutions for environmental water analysis. By leveraging automated sample introduction, direct injection, and tandem MS or simultaneous optical detection, laboratories can meet evolving regulatory demands and enhance operational efficiency.

Reference

[1] M.C. Díaz Ramos et al., ‘‘Determination of 24 PAHs in Drinking Water,’’ Agilent Technol. Appl. Notebook, 2012.
[2] J.A. Shoemaker, EPA Method 538, ‘‘Determination of Selected Organic Contaminants in Drinking Water by Direct Aqueous Injection-LC/MS/MS,’’ EPA/600/R-09/149, 2009.
[3] M. Pinchin and S. Verik, ‘‘Analyzing Wastewater Effluents for PAHs and PBDEs Using the Agilent 7000 GC/MS/MS,’’ Appl. Notebook, 2012.
[4] D. Hoobin, ‘‘Ultra-Fast ICP-OES Determination of Trace Elements in Water, Conforming to U.S. EPA 200.7,’’ Appl. Notebook, 2012.