Analysis of 1,4-Dioxane in Drinking Water Using the Teledyne Tekmar Lumin P & T Concentrator, AQUATek LVA and Agilent 7890B GC/5977A MSD

Significance of the Topic

1,4-Dioxane is a regulated volatile organic compound widely monitored in drinking water due to its potential health hazards. Its high solubility and low volatility make conventional purge and trap approaches less efficient, driving the need for optimized sample preparation and detection methods that achieve reliable part-per-billion quantitation.

Objectives and Study Overview

This application study aimed to develop and validate an analytical workflow combining a Teledyne Tekmar Lumin P&T concentrator, an AQUATek LVA liquid autosampler, and an Agilent 7890B GC/5977A MS in SIM mode. The goal was to produce a linear calibration curve for 1,4-dioxane from 0.2 to 50 ppb, determine method detection limits (MDLs), and assess accuracy and precision at low-level concentrations.

Methodology and Used Instrumentation

The workflow employed a purge and trap concentration with moisture control, followed by GC/MS analysis. Key parameters included:

• Teledyne Tekmar Lumin and AQUATek LVA: optimized purge (20–100 mL/min) and bake cycles, trap temperature control, and liquid autosampler settings.
• Agilent 7890B GC: Rtx-VMS column (20 m × 0.18 mm, 1 μm), oven ramp from 35 °C to 225 °C, split inlet at 80:1.
• Agilent 5977A MSD: SIM ions m/z 88 for 1,4-dioxane and m/z 96 for d8 internal standard, transfer line at 225 °C.

Main Results and Discussion

The method produced a linear calibration (r² = 0.9996) over 0.2–50 ppb. Seven replicate 0.5 ppb standards yielded an average recovery of 0.55 ppb with 2.56 %RSD, establishing an MDL of 0.04 ppb. Selective ion monitoring effectively minimized water interference and enhanced sensitivity.

Benefits and Practical Applications

• Reliable detection of 1,4-dioxane at sub-ppb levels in drinking water matrices.
• Reduced moisture interference and extended GC column lifetime via improved moisture control.
• High reproducibility and precision support regulatory compliance and routine QA/QC workflows.
• Potential for shortened cycle times and increased laboratory throughput with minor GC oven adjustments.

Future Trends and Opportunities

Continued innovation in moisture management and autosampler automation may further lower detection limits and enhance robustness. Integration of faster GC columns and advanced MS detection modes (e.g. high-resolution MS) could expand the method to multi-residue analysis of emerging contaminants. Automation and data processing advances will enable higher throughput and real-time monitoring capabilities.

Conclusion

The optimized P&T–GC/MS method using the Teledyne Tekmar Lumin, AQUATek LVA, and Agilent 7890B/5977A system provides sensitive, precise, and reproducible analysis of 1,4-dioxane in drinking water down to 0.2 ppb. This approach meets stringent regulatory requirements while offering scalability for high-volume environmental testing.