SPE-GCxGC-TOFMS for Detection of Di si nf ection By-Products and Endocrine Di sruptors in Munici pal Water, Residential Swimming Pools, and Purified Bottled Drinking Water

Importance of the Topic

Drinking water disinfection is vital for public health but generates potentially harmful by-products and endocrine disruptors that pose mutagenic, carcinogenic, and reproductive risks. Comprehensive analytical techniques are required to detect these trace contaminants in various water matrices.

Study Objectives and Overview

This study presents an untargeted screening approach combining solid-phase extraction (SPE) with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–TOFMS) to identify disinfection by-products (DBPs) and endocrine disrupting compounds (EDCs) in municipal tap water, residential swimming pools, and bottled drinking water. The goal was to match detected compounds to EPA DBP lists and the TEDX endocrine disruptor list, assessing method sensitivity and scope.

Methodology

Water samples (1 L) were processed using hydrophilic–lipophilic balance (HLB) SPE cartridges. Cartridges were conditioned, sample loaded at 2–3 drops/s, dried under vacuum, and eluted sequentially with acetone/methanol and methylene chloride. Extracts were concentrated to ~150–200 µL before GC×GC–TOFMS analysis.

Instrumentation

• Gas chromatograph: Agilent 7890 coupled to LECO dual-stage thermal modulator and GERSTEL MPS2 autosampler.
• Primary column: Restek Rxi-5Sil MS (30 m × 0.25 mm, 0.25 µm film).
• Secondary column: Restek Rxi-17Sil MS (1.25 m × 0.18 mm, 0.18 µm film).
• Carrier gas: Helium (1.0 mL/min); injection: splitless, inlet 250 °C.
• Temperature programs: 30 °C→295 °C and 40 °C→305 °C ramps at 6 °C/min.
• Modulation period: 5 s; transfer line: 250 °C.
• TOFMS: LECO Pegasus 4D; mass range 35–800 m/z, 200 spectra/s, source 230 °C, detector 1425 V.

Main Results and Discussion

A total of 37 DBPs were identified, spanning halomethanes, haloaldehydes, haloacetonitriles, haloketones, halonitromethanes, haloamides, and haloacetic acids, aligning with EPA Method 551.1 and the 2005 National Occurrence Study. Chloroform calibration (46.4 pg–24.7 ng) achieved r=0.9994; sample concentrations ranged from 0.046 ng/µL (bottled water) to 0.741 ng/µL (swimming pool). Ten EDCs were detected by comparison to the TEDX list, including bisphenol A, phenols, benzene derivatives, and polyaromatic hydrocarbons. Two-dimensional contour plots and extracted ion chromatograms demonstrated excellent separation and sensitivity across complex matrices.

Benefits and Practical Applications

• Comprehensive detection of a wide chemical space in a single untargeted analysis.
• High sensitivity with true signal deconvolution for low-level contaminants.
• Reproducible SPE workflow suitable for routine monitoring.
• Applicable to regulatory compliance, research, and QA/QC in water quality laboratories.

Future Trends and Potential Applications

Emerging developments in high-resolution two-dimensional chromatography and real-time data processing will broaden detection of novel transformation products. Integration with toxicological assays and portable GC×GC–MS platforms may enable in-field risk-based assessments and faster response to water quality incidents.

Conclusion

The SPE–GC×GC–TOFMS workflow offers a robust, sensitive platform for untargeted screening of DBPs and endocrine disruptors in drinking and recreational waters. It fulfills regulatory screening criteria and supports comprehensive water safety evaluation.

References

1. US Environmental Protection Agency. EPA Method 551.1: Determination of Halogenated Organic Disinfection Byproducts in Drinking Water by Liquid–Liquid Extraction and Gas Chromatography with Electron Capture Detection; US EPA: Washington, DC, 1995.
2. Richardson, S.D.; Anduri, S.; Bloodgood, M.; Plewa, M.J.; Jeong, E.; Wagner, E.D.; Nieuwenhuijsen, M.; Kogevinas, M.; Villanueva, C.M.; Luo, W.; Isabelle, L.; Pankow, J. Combining Mass Spectrometry and Toxicology for a Multi-Country European Epidemiologic Study on Drinking Water Disinfection By-Products. Presented at ASMS Conference, Florida, May 20–24, 2012.